AS 3740-2010 (with Amdt 1 2012) Waterproofing of Domestic Wet Areas

AS 3740—2010 3740—2010

A S 3 7 4 0 — 2 0 1 0

Australian Standard

®

Waterproofing of domestic wet areas

This Australian Standard® Standard® was prepared by Committee BD-038, Wet Areas in Buildings. It was approved on behalf of the Council of Standards Australia on 9 September 2010. This Standard was published on on 5 November 2010.

The following are represented represented on Committee Committee BD-038: • • • • • • • • • • • • • • • • • • •

Architectural Aluminium Aluminium Fabricators Association Association (NSW) Australian Building Codes Board Board Australian Chamber of Commerce Commerce and Industry Australian Consumer Association Association CHOICE Australian Institute of Building Building Surveyors Australian Institute of Waterproofing Waterproofing Australian Tile Council Building Research Association of New Z ealand Business New Zealand CSIRO, Manufacturing and Infrastructure Technology Engineered Wood Products Association of Australasia Federation of Wall and Ceiling Industries Australia and New Zealand Housing Industry Australia Institute of Materials Engineering Australasia Master Builders Australia Planning South Australia South Australia Housing Trust TAFE NSW Timber Queensland

This Standard was issued in draft draft form for comment comment as DR 09057. Standards Australia wishes to acknowledge the participation of the expert individuals that contributed to the development of this Standard through their representation on the Committee and through the public comment period.

Australian Standards® are are living documents documents that reflect progress in in science, technology and and systems. To maintain their currency, all Standards are periodically reviewed, and new editions are published. Between editions, amendments may be issued. Standards may also be withdrawn. It is important that readers assure themselves they are using a current Standard, which should include any amendments that may have been published since the Standard was published. Detailed information about Australian Standards, drafts, amendments and new projects can be found by visiting Standards Australia welcomes suggestions for improvements, and encourages readers to notify us immediately of any apparent inaccuracies or ambiguities. Contact us via email at , or write to Standards Australia, GPO Box 476, Sydney, NSW 2001.

AS 3740—2010 3740—2010

Australian Standard

®

Waterproofing of domestic wet areas

Originated as AS 3740—1989. Fourth edition 2010.

COPYRIGHT

© Standards Australia Limited All rig hts are res erv ed. No par t o f t his wor k m ay be rep rod uce d o r c opie d i n a ny for m o r b y any means, electronic or mechanical, including photocopying, without the written permission of the publisher, unless otherwise permitted under the Copyright Act 1968. Published by SAI Global Limited under licence from Standards Australia Limited, GPO Box 476, Sydney, NSW 2001, Australia ISBN 978 0 7337 9703 3

AS 3740 —201 0

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PREFACE

This Standard was prepared by the Standards Australia Committee BD-038, Wet Areas in Buildings, to supersede AS 3740—2004, Waterproofing of wet areas within residential buildings. buildings. The objective of this Standard is to set out the criteria for waterproofing wet areas within domestic buildings. It gives minimum requirements for materials, designs and installations. installations. The objective of this revision is to bring this Standard in line with the current waterproofing practices in the building industry. Changes to the previous edition include the following: (a)

Risk levels of different areas.

(b)

Appropriate details for various risk levels.

(c)

Clarification of usage definitions.

(d)

Increased ease of reference for varying conditions.

(e)

Revised design and installation techniques.

This Standard is not to be interpreted as preventing the use of materials, systems or methods that meet the design and installation criteria set out in the Standard, but are not specifically referred to herein (alternative solution). Additional requirements may need to be considered for wet areas intended for use by people with disabilities. The term ‘informative’ has been used in this Standard to define the application of the appendix to which it applies. An ‘informative’ appendix is only for information and guidance. Statements expressed in mandatory terms in notes to tables and figures are deemed to be requirements of this Standard. AMDT No. 1 DEC 2012

Additional change to the previous edition is the inclusion of Appendix C, which provides guidance on the extent of waterproofing for wet areas.

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AS 3740 —201 0

CONTENTS

Page FOREWORD................................................. FOREWORD............... .................................................................... .................................................................... ........................................... ......... 4 SECTION 1 SCOPE AND GENERAL 1.1 SCOPE .................................................................. .................................................................................................... ...................................................... .................... 5 1.2 APPLICATION APPLICATION ................................................................ .................................................................................................. ........................................... ......... 5 1.3 NORMATIVE REFERENCES................................................ REFERENCES.................................................................................. .................................... .. 5 1.4 DEFINITIONS ................................................................ .................................................................................................. ............................................ .......... 6 SECTION 2 MATERIALS 2.1 SCOPE OF SECTION ................................................................. ................................................................................................. ................................ 9 2.2 DESIGN AND INSTALLATION............................... INSTALLATION................................................................. ................................................. ............... 9 2.3 MOVEMENT JOINTS ................................................................. ................................................................................................ ............................... 9 2.4 MATERIALS ................................................................... ..................................................................................................... ........................................... ......... 9 2.5 PREFORMED SHOWER BASES AND ENCLOSURES........................................ ENCLOSURES.......................................... .. 10 2.6 SEALANTS........................................................................................ SEALANTS............................................................................................................... ....................... 11 2.7 ADHESIVES...................................................................................... ADHESIVES............................................................................................................. ....................... 11 2.8 SHEET FASTENINGS.............................. FASTENINGS................................................................ ................................................................ .............................. 11 SECTION 3 INSTALLATION 3.1 SCOPE OF SECTION ................................................................. ............................................................................................... .............................. 12 3.2 GENERAL .................................................................. .................................................................................................... .............................................. ............ 12 3.3 FALLS IN FLOOR FINISHES......................................................... FINISHES.................................................................................. ......................... 12 3.4 SHOWER FLOORS ............................................................... ................................................................................................. .................................... 12 3.5 CURING OF MATERIALS............................................. MATERIALS................................................................................ .......................................... ....... 12 3.6 PREFORMED SHOWER BASES........................................................... BASES............................................................................. .................. 12 3.7 EDGE DETAIL FOR BATHS WITH SHOWERS OVER THEM............................. 13 3.8 BATHS AND SPAS ................................................................... .................................................................................................. ............................... 14 3.9 JUNCTIONS .................................................................... ...................................................................................................... ......................................... ....... 16 3.10 PENETRATIONS.............................................................................. PENETRATIONS...................................................................................................... ........................ 18 3.11 REQUIRED FLOOR WASTES FOR WET AREA FLOORS ................................... ................................... 19 3.12 WALL SHEETING OR RENDER...................................................... RENDER............................................................................. ....................... 20 3.13 GENERAL SHOWER AREA REQUIREMENTS................... REQUIREMENTS..................................................... .................................. 20 3.14 MEMBRANE TO DRAINAGE CONNECTION......................... CONNECTION....................................................... .............................. 27 3.15 INSTALLATION OF AN INTERNAL MEMBRANE .............................................. .............................................. 28 3.16 INSTALLATION OF AN EXTERNAL MEMBRANE............................................. 31 3.17 DOORJAMBS AND ARCHITRAVES........................................ ARCHITRAVES...................................................................... .............................. 32 3.18 SHOWER SCREEN ..................................................................... .................................................................................................. ............................. 32 APPENDICES A DESIGN CONSIDERATIONS IN WET-AREA WATERPROOFING WATERPROOFING ..................... 34 B FALLS IN FLOOR FINISHES......................................................... FINISHES.................................................................................. ......................... 37 BIBLIOGRAPHY .................................................................... ....................................................................................................... ................................................ ............. 38

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FOREWORD

Since the last edition of this Standard was published in 2004, it had become increasingly apparent that various methods for design and installation of waterproofing systems outlined in the document no longer represented minimum acceptable standards and a further review was required. In this document, the Committee has attempted to address these shortcomings. This revision is intended to cover the treatment of wet areas within domestic buildings in a form that makes the application of accepted methods more relevant to the various risk levels, while presenting typical detail diagrams relevant to those applications. Problems with waterproofing defects relate to a number of fundamentals, including the following: (a)

Workmanship.

(b)

Understanding of material technology/properties.

(c)

Applicator skill and competence.

(d)

Application to a variety of use situations.

(e)

Changes in design trends.

(f)

Quality control, including supervision, inspection and testing.

(g)

Maintenance of waterproofing medium when disturbed.

(h)

Fixture of fittings after waterproofing and tiling.

(i)

Professional attitude and a desire to continuously improve without without compromising quality, performance and contractual obligations (where they exceed minimum requirements).

This Edition of the Standard differs from the 2004 edition in that the Design Section has been removed and included in the Building Code of Australia (BCA).

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AS 3740 —201 0

STANDARDS AUSTRALIA

Australian Standard Waterproofing of domestic wet areas

S E C T I O N

1

S C O P E

A N D

G E N E R A L

1.1 SCOPE

This Standard sets out minimum requirements for the materials, design and installation of waterproofing for domestic wet areas. The Standard does not cover situations where flooding of the wet areas occurs through overflowing of vessels and showers or plumbing failures and excludes concrete admixtures or penetrant sealers or similar and decorative coatings. NOTE : Appen A ppendix dix A provi p rovi des design des ign cons iderat ider ations ions for wet area wat erproofi erpr oofi ng.

1.2 APPLICATION

This Standard applies to wet areas in Class 1, Class 2 and Class 4 buildings as defined in the BCA. It also applies to wet areas within other buildings with a similar level of use including sole-occupancy units within a Class 3 building. NOTE : This Th is Sta ndard is not intend int ended ed to appl y to com mun munal al or grou p wet area s suc h as sho wer areas as in swimming pool complexes, sporting facilities and similar situations.

1.3 NORMATIVE REFERENCES

The following are the normative documents referenced in this Standard: NOTE : Docum Do cum ent s r eferen efe renced ced for inform inf ormati ati ve p urposes urpo ses are lis ted in the Bibl iograph iog raph y.

AS 1566

Copper and copper alloys—Rolled flat products

1684 1684.2 1684.3 1684.4

Residential timber-framed construction Part 2: Non-cyclonic areas Part 3: Part 4: Simplified—Non-cyclonic areas

1860 1860.2

Particleboard flooring Part 2: Installation

2870

Residential slabs and footings—Construction

2924 2924.1

High pressure decorative laminates—Sheets laminates—Sheets made from thermosetting resins Part 1: Classification Classification and specifications

3600

Concrete structures

3700

Masonry structures

AS/NZS 1170 Structural design actions 1170.1 Part 1: Permanent, imposed and other actions 1170.2 Part 2: Wind actions 1860 1860.1

Particleboard flooring Part 1: Specifications Specifications

ww w.s tan dard s.o rg. au

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AS/NZS 2269 Plywood—Structural 2588

Gypsum plasterboard

2908 2908.2

Cellulose-cement products Part 2: Flat sheets

4858

Wet area membranes

BCA

Building Code of Australia

1.4 DEFINITIONS

For the purpose of this Standard, the definitions below apply. 1.4.1 Backing rod

A section of closed cell foam made from flexible plastics. 1.4.2 Bond breaker

A system that prevents the membrane bonding to the substrate, bedding or lining. 1.4.3 Drainage flange

A flange connected to a waste pipe, at the point at which it passes through the floor substrate, to prevent leakage and enable tile bed drainage into the waste pipe. 1.4.4 Drainage riser

A waste pipe between the floor waste and the drainage system. 1.4.5 Flashing

A strip or sleeve of impervious material dressed, fitted or built in, or a liquid-applied product, to provide a barrier to moisture movement, divert the travel of moisture, or cover a joint join t where w here water wate r woul w ould d other ot herwise wise penetrate penet rate.. 1.4.6 Flashing, perimeter

A flashing used at the floor-wall junction. 1.4.7 Flashing, vertical

A flashing used at wall junctions within shower areas. 1.4.8 Floor waste

A grated inlet within a graded floor intended to drain the floor surface (see Clause 3.14.2). 1.4.9 Hob

The upstand at the perimeter a s hower area. 1.4.10 Insert bath

A bath where the bath lip is installed onto a horizontal plinth or surface. 1.4.11 Maximum retained water level

The point at which surface water will start to overflow out of the shower area. 1.4.12 Membrane

A barrier that is impervious to moisture. NOTE : A barrier barr ier may be a s ing le or mul ti-par ti- partt s yst em.

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AS 3740 —201 0

1.4.13 Membrane, external

A membrane that is installed behind the wall sheeting or render. NOTE : Us ually ual ly extern ext ernal al membra mem bra nes are pref orme d t rays ray s or s heet mat erial eri al sys tem s.

1.4.14 Membrane, internal

A membrane that is installed to the face of the wall sheeting or render. NOTE : Us ually ual ly intern int ernal al membra mem bra nes are liquid liq uid sys tem s appl ied in sit u.

1.4.15 Nib wall wall that that forms part of shower enclosure

A low height wall that supports part of a shower screen. 1.4.16 Prefinished wall panels

Predecorated sheets or thermosetting laminated sheets that are designed for use as the final wall finish of the wet area. 1.4.17 Preformed shower base

A preformed, prefinished vessel (including integral upstands) installed as the finished floor of a shower compartment, and provided with a connection point to a sanitary drainage system. NOTE : Sh owe r bases bas es are common com mon ly mad e of plasti pla stics, cs, composi com posi te mat eria ls, vitreo vit reous us enam ell ed pressed steel, or stainless steel.

1.4.18 Shower screen

The panels, doors or windows enclosing or partially enclosing a shower area (see Clause 3.18). 1.4.19 Shower tray

An internal or external liquid or sheet membrane system used to waterproof the floor and the wall/floor junctions of a shower area. 1.4.20 Shower area

The area affected by water from a shower, including a shower over a bath. 1.4.21 Shower area, enclosed

The area enclosed by walls or screens, including hinged or sliding doors, that control the spread of water to within the enclosure. 1.4.22 Shower area, unenclosed

A shower area where, under normal use, water out of the shower rose is not contained within the shower area (see Clause 3.13.5). 1.4.23 Vessel

An open, preformed, prefinished concave receptacle capable of holding water, usually for the purpose of washing (e.g., basin, sink, bath, laundry tub). 1.4.24 Waterproof (WP)

The property of a material that does not allow moisture to penetrate through it when tested in accordance with AS/NZS 4858. NOTE : Fo r the purpose purp ose s of thi s Standa Sta ndard, rd, for mat erials eri als deem ed to be wat erproof erp roof and sui table tab le for including in a waterproofing system, see Clause 2.4.1.


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1.4.25 Waterproofing system

A combination of elements that are required to achieve a waterproof barrier as required by this Standard (e.g., substrate, membrane, b ond breakers, sealants and finishes). NOTE : A wat erproof erpr oofing ing sys tem for a bathroo bat hroom m flo or may inc lude lud e lining lin ing it wit h a mat eri al in accordance with Clause 2.4.1, Item (a), (b) or (d) or by using a waterproof flexible sheet flooring material in accordance with Clause 2.4.1(c).

1.4.26 Water resistant (WR)

The property of a system or material that restricts moisture movement and will not degrade under conditions of moisture. 1.4.27 Water stop

A vertical extension of the waterproofing system for ming a barrier to prevent the passage of moisture in the floor. 1.4.28 Wet area

An area within a building supplied with water from a water supply system, which includes bathrooms, showers, laundries and sanitary compartments and excludes kitchens, bar areas, kitchenettes or domestic food and beverage preparation areas. 1.4.29 Wicking

The action of water rising by a capillary path.

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S E C T I O N

2

AS 3740 —201 0

M A T E R I A L S

2.1 SCOPE OF SECTION

This Section sets out requirements for acceptable materials to be used in the waterproofing of wet areas. 2.2 DESIGN AND INSTALLATION

Waterproofing systems and their installation details shall be waterproof or water resistant as required by the BCA. In addition, waterproofing systems and their installation details shall be compatible and shall resist the following: (a)

(b)

Differential movement due to— (i)

actions as defined in AS/NZS 1170.1 and AS/NZS 1170.2;

(ii)

shrinkage and expansion of substrate materials, framing and finishes;

(iii)

temperature variations from −5°C to +50°C; and

(iv)

movement tolerances as defined in AS 2870.

Exposure to— (i)

cleaning chemicals [such as detergents, sodium hypochlorite (bleach)], as required by AS/NZS 4858; and

(ii)

alkalis from cement mortar as required by AS/NZS 4858.

2.3 MOVEMENT JOINTS

The waterproofing system shall accommodate the expected movement at movement joints in the substrate. 2.4 MATERIALS 2.4.1 Waterproof

For the purposes of this Standard, the following materials used in waterproofing systems are deemed to be waterproof: (a)

Stainless steel.

(b)

Copper, material not less than 99.9% copper, complying with the requirements for material designation 110 or 122 given in AS 1566.

(c)

Flexible waterproof sheet flooring material with waterproof joints of the sheeting. NOTE : Th ere is no need nee d for a water wa ter stop sto p at the gen genera erall room door way whe n usi ng this th is material.

(d)

Membranes meeting the requirements of AS/NZS 4858.


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2.4.2 Water-resistant substrates

For the purposes of this Standard, the following materials used in waterproofing systems, in conjunction with water-resistant surface materials in accordance with Clause 2.4.3, are deemed to be water r esistant: (a)

Walls: Walls: (i)

Concrete in accordance with AS 3600, treated to resist moisture movement.

(ii)

Cement render treated to resist moisture mov ement. NOTE : For F or r ecom mended men ded prac tice, tic e, see HB 161, 1 61, Guide Gui de to p las tering ter ing .

(b)

(iii)

Fibre cement sheeting manufactured in accordance with AS 2908.2.

(iv)

Water-resistant plasterboard sheeting manufactured in accordance with AS/NZS 2588.

(v)

Masonry in accordance with AS 3700.

Floors Flo ors:: (i)

Concrete in accordance with AS 3600 and AS 2870.

(ii)

Compressed fibre cement sheeting manufactured in accordance with AS 2908.2.

(iii)

Fibre cement sheeting man ufactured in accordance with AS 2908.2, and supported on a structural floor.

(iv)

Flooring grade particleboard sheeting manufactured in accordance with AS/NZS 1860.1, and installed in accordance with AS 1860.2.

(v)

Structural plywood manufactured in accordance with AS/NZS 2269, and installed in accordance accordance with AS 1684.2, AS 1 684.3 and AS 1684.4.

2.4.3 Water-resistant surface materials

For the purposes of this Standard, the following surface materials are deemed to be water resistant for the locations listed: (a)

Walls: Walls: (i)

Thermosetting laminated sheet manufactured in accordance with AS 2924.1.

(ii)

Predecorated AS 2908.2.

(iii)

Tiles when used in conjunction with a substrate listed in Clause 2.4.2.

fibre

cement

sheeting

manufactured

in

accordance

with

NOTE : Po rous til es can hav havee di scol oura tion tio n ca used use d by wat er absorpt abso rption ion and mig ration. rat ion.

(b)

(iv)

Water-resistant flexible sheet wall material with sealed joints (e.g., sheet vinyl or linoleum) when used in conjunction with a substrate listed in Clause 2.4.2.

(v)

Sanitary grade acrylic wall linings.

Floors Flo ors (when (when used in conjunction with a substrate listed in Clause 2.4.2): (i)

Tiles. NOTE : Po rous til es can hav havee di scol oura tion tio n ca used use d by wat er absorpt abso rption ion and mig ration. rat ion.

(ii)

Water-resistant flexible sheet flooring material with sealed joints (e.g., sheet vinyl vin yl and linoleu lino leum.) m.)

2.5 PREFORMED, PREFINISHED SHOWER BASES AND ENCLOSURES

Materials used in the manufacture of preformed, prefinished shower bases and enclosures shall be such that the finished product is waterproof. ©

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AS 3740 —201 0

2.6 SEALANTS

For the purposes of this Standard, all sealants shall be— (a)

waterproof;

(b)

flexible;

(c)

mould-resistant; and

(d)

compatible with adjacent materials.

2.7

ADHESIVES

Adhesives used in a waterproofing system shall be— (a)

waterproof, where used to adhere other waterproof materials; and

(b)

compatible with the materials to which they are adhered.

2.8 SHEET FASTENINGS

Substrate sheet materials shall be fastened or fixed adequately to the supporting structure.


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S E C T I O N

3

I N S T A L L A T I O N

3.1 SCOPE OF SECTION

This Section sets out details for the installation of waterproof and water-resistant materials to be used in domestic wet areas of a building. 3.2 GENERAL

Where a tile bed or screed is used, the waterproof membrane shall be installed above or below the tile bed or screed. AMDT No. 1 DEC 2012

NOTE : Fo r the purpose purp osess of thi s Standa St anda rd, some som e fig ure s given giv en in this thi s Sect ion ill ust rate rat e the membrane below the tile bed or screed; however, where applicable, the membrane may be installed above the tile bed or screed. Guidelines for extent of waterproofing for showers and wet areas are given in Figures C1 and C2, Appendix C.

3.3 FALLS IN FLOOR FINISHES

Where required, falls in floor finishes shall allow all surface water to drain without ponding except for residual water remaining due to surface tension. For general bathroom floor area, the minimum fall to the w aste shall be 1:100. NOTE S: 1

For information on falls in the floor finishes, see Appendix B.

2

For information on the laying of tiles to enable them to drain without retaining water, see AS 3958.1.

3.4 SHOWER FLOORS

Falls in shower floors shall be sufficient to prevent— (a)

surface water from being retained on the shower floor (except for residual water remaining due to surface tension); and

(b)

water from discharging outside the shower area.

For shower areas with a vertical separation between the shower area and the wet area, such as a shower screen, hob, step-down or water stop, the fall to the waste shall be 1:100. As a minimum f or other shower areas, the fall shall be a minimum of 1:80. 3.5 CURING OF MATERIALS

Materials shall be cured adequately for their intended use. NOTE : The membra mem bra ne sho uld be prot ected ect ed from fro m physic phy sic al and/or and /or chemic che mic al dama ge unt il cove red by the finished surfaces.

3.6 PREFORMED SHOWER BASES

Preformed shower bases shall be supported to prevent distortion or cracking, and shall be sufficiently recessed into the wall to allow the water-resistant surface materials to pass down inside the perimeter rebate over the upstands of the shower base. NOTE : Fo r t ypic al base bas e junct j unct ion, see Fig ures ure s 3.1(a 3 .1(a)) a nd 3.1(b 3 .1(b). ).

When installing preformed shower bases, the integrity of the structure shall be maintained.

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AS 3740 —201 0

AMDT No. 1 DEC 2012

3.7 EDGE DETAIL FOR BATHS WITH SHOWERS OVER THEM 3.7.1 Baths to be recessed into a wall

Baths recessed into a wall shall have an integral vertical upstand lip along the side of the bath walls to enable a waterproof junction between the bath and walls. 3.7.2 Baths with a downturn lip AMDT No. 1 DEC 2012

Baths withoutananintegral integral upstand but with a downturn lipbeshall be installed asbath an insert Baths without upstand but with a downturn lip shall installed as an insert bath, as specified Clause 3.8. as shown in Figure in 3.2(c). 3.7.3 Baths without an integral edge to allow for for a vertical upstand for termination of of waterp wat erproo roofing fing

AMDT No. 1 DEC 2012

baths that that do do not not have have an anintegral integral edge edgedetail detailtofor a vertical termination of the of the For baths allow for a vertical termination waterproofing, thereshall shall be full waterproofing theand walls waterproofing, there be full waterproofing of the of walls floorand area floor and area and waterproofing underthe thebath. bath. The enclosed space under t he bath be ventilated. waterproofing under The enclosed space under the bath shallshall be ventilated. Extent of NOTE waterproofing asuired forda to Type specified innd Clause 3.13.5. : Ve nti lation latshall ion isberequire req allo2wunenclosed eva pora tion tio nshower, of wat erasleakin lea kin g around arou the edge edg e of the bath bat h into the enclosed airspace under the bath.

3.7.4 Freestanding baths with shower over For freestanding baths with shower over, the extent of waterproofing shall be as for a Type 2 unenclosed shower, ignoring bath, as specified in Clause 3.13.5 and as depicted in Figure 3.1A.


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AMDT No. 1 DEC 2012

Waterproof wall to wall junction, 1800 from finished floor level, width of 40 either side of the j un c ti o n (s e e N ot e 1)

1500 Measured from the shower connection

WP

Floor waste

Waterproof a minimum of 1500 from shower connection at wall and grade to a floor waste and terminate at a waterstop

(a) Plan view

15 0 0

WR

40

Shower rose

1800 Freestanding bath WP

A l l f l oo r un d e r f r e e s t a n di ng b a t h t o be wa t e r p r o of e d

(b) Elevation

NOTES: 1

Waterproofing of all wall junction is only required if shower rose is located within 1500 from junction.

2

All floor waterproofing to terminate at a waterstop.

3

For timber floors, entire floor to be waterproofed. DIMENSIONS IN MILLIMETRES

FIGURE 3.1A

FREESTANDING BATHS

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FIGURE 3.1 TYPICAL PREFORMED SHOWER BASE JUNCTIONS

3.8 BATHS AND SPAS

Baths and spas shall be supported to prevent distortion and cracking. Baths and sp as that are recessed into the wall shall be installed to allow the water-resistant surface materials of the wall to pass down inside the rim of the bath or sp a. NOTE : Fo r t ypic al bath/s bat h/spa pa wal l junc j unctio tions ns see Fig ures 3.2(a) 3.2( a) and 3.2(b). 3.2( b).

When installing baths and spas, the integrity of the structure shall be maintained.

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AMDT No. 1 DEC 2012

Water-resistant surface material of the wall Structural support Waterproof sealant Wall rebated to accommodate rim of bath Bath

(a) Bath/wall junction—Recessed

Water-resistant sheeting Water-resistant surface material of the wall

Battens to support wall sheet to allow the rim of the bath to fit behind the wall sheet (battens shown are diagrammatic only and are not to scale)

Waterproof sealant

Structural support

Bath

(b) Bath/wall junction—Battened Min 100 mm for shelf

Support to membrane Waterstop

Waterproof sealant Tile

Membrane 5 mm above tile

Membrane

Bath

Tile underlay Bath frame (i) Bath with rim

Min 100 mm for shelf

Support to membrane Waterstop

Waterproof sealant Tile

Membrane 5 mm above tile

Membrane

Bath

Tile underlay Bath frame (ii) Bath without rim (c) Bath/shelf junction (insert bath) FIGURE 3.2

TYPICAL BATH JUNCTIONS

AS 3740 —201 0

3.9

16

JUNCTIONS

3.9.1 Perimeter flashing 3.9.1.1 General

The following list specifies the minimum requirements for the treatment for various junction junc tions. s. Junctio Junc tions ns may be either eith er wall to floor flo or or wall to wall. wall . Either Eith er the floor flo or or wall may be waterproof, water resistant or have no treatment specified. The types of junctions that shall be used are as follows: (a)

Type 1 Where waterproof to waterproof surfaces surfaces meet, the the waterproofing shall shall be continuous across the junctions and, where required, incorporate an appropriate bond breaker.

(b)

Type 2 Where waterproof to water-resistant surfaces meet, a bead of sealant sealant shall be deemed to be a waterproof junction.

(c)

Type 3 Where water-resistant to water-resistant surfaces surfaces meet, a bead of sealant shall be deemed to be a water-resistant junction. junction.

(d)

Type 4 Where non-water-resistant non-water-resistant to water-resistant water-resistant surfaces surfaces meet, a bead of sealant sealant shall be deemed to be a water-resistant junction. junction.

(e)

Type 5 Perimeter flashing flashing to wall/floor surfaces surfaces shall be continuously sealed sealed to the horizontal surface and have a vertical leg of a minimum of 25 mm above the finished floor level, except across doorways, and the horizontal leg shall be a minimum width of 50 mm.

3.9.1.2 Perimeter Peri meter flashing flas hing at floo f loorr level le vel opening open ingss

The following applies: (a)

For whole whol e wet w et area a rea floor floo r water w aterpro proofin ofing g A water stop that has a vertical leg finishing flush with the top of the finished floor level shall be installed at floor level openings. The floor membrane shall be terminated to create a waterproof seal to the water stop and to the perimeter flashing. NOTE : For F or typ ica l bathroo bat hroo m detail det ail for who le bathroo bat hroo m wat erproofi erpr oofi ng, see Fig ures ure s 3.3(a 3 .3(a)) and 3.3(b).

(b)

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For other othe r than tha n whole whol e wet area floor flo or waterpr wate rproofi oofing ng A water stop that has a vertical vertical leg finishing flush with the top of the finished floor level shall be installed at floor level openings. The water stop shall be waterproofed to the perimeter flashing.

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FIGURE 3.3


AS 3740 —201 0

TYPICAL BATHROOM DOOR DETAIL FOR WHOLE BATHROOM WATERPROOFING

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3.9.2 Vertical flashing for shower wall junctions

Vertical flashing may be external or internal and shall terminate a minimum of 1800 mm, above the finished floor level or to the height of the wall, whichever is the lesser. Vertical flashing may be used as follows: (a)

External vertical flashing may be used with external membranes systems and installed behind the wall sheeting or render, provided they have legs of sufficient width to allow the wall sheeting or render to overlap by a minimum of 30 mm. (The mechanical fastening of the wall sheeting shall not penetrate the flashing.)

(b)

Internal vertical flashing may be used with both external and internal membrane systems, provided each leg has a minimum overlap of 40 mm to the wall sheeting or render and, where used with—

3.10

(i)

internal membranes, each leg extends vertically from w ithin the shower tray;

(ii)

external membranes, each leg overlaps the top edge of the floor waterproofing system, by a minimum 20 mm; and

(iii)

preformed shower bases or baths, each leg extends to the bottom edge of the wall sheeting or render.

PENETRATIONS

3.10.1 Shower areas

Penetrations for taps, shower nozzles, recessed soap holders and similar fixtures shall be waterproofed by sealing with proprietary flange systems or a sealant. When sealing the tap body to the wall, allowance shall be made for the servicing of tap washers or ceramic disks without damaging the seal. NOTE : Typic Ty pical al det ail for recess rec ess ed s oap hold ers is shown sho wn in Fig ure 3.4.

For mixer taps, drainage shall be allowed at the base of the cover plate. Any penetrations of mechanical fixings or fastenings through surface materials shall be waterproofed.

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FIGURE 3.4 TYPICAL DETAIL FOR RECESSED SOAP HOLDERS

3.10.2 Tap penetrations through horizontal surfaces

Tap penetrations on horizontal surfaces surrounding baths and spas shall be waterproofed by sealing with proprietary flange systems or the tap body to the membrane, or substrate where a membrane is not required. 3.11 REQUIRED FLOOR WASTES FOR WET AREA AREA FLOORS

Where a floor waste is required, the floor finish shall be constructed so that water flows to the waste without water being retained on the finished surface with the exception of residual water remaining due to surface tension. NOTE : Fo r addit ad dit iona l i nfor mat ion on floor floo r gradi g radi ent s, see Appe ndix ndi x B.


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3.12 WALL SHEETING OR RENDER

Where wall sheeting or render is used with an external membrane system in a shower area, it shall— (a)

not extend into the floor tile bed; or

(b)

be waterproofed to prevent moisture movement by capillary action or wicking.

For water-resistant plasterboard sheeting, all cut edges that have the potential to be affected by moisture shall be waterproofed, including the bottom edge over a preformed shower base. The water-resistant plasterboard sheeting shall be kept a minimum of 5 mm above the preformed shower base to allow effective sealing of the cut edge of the plasterboard. 3.13 GENERAL SHOWER AREA REQUIREMENTS 3.13.1 Substrate surface preparation for application of a membrane

The area shall be cleaned and dust free. Indentations and imperfections shall be kept to a minimum and repaired where necessary. 3.13.2 Step-down showers

The highest finished floor level of the shower area shall be stepped down lower than the finished floor level outside the shower NOTE : Fo r ex amp les , s ee Fig ure 3.5.

For set-downs less than 15 mm, d etails shall be in accordance with Clause 3.13.4 or Clause 3.13.5, as appropriate.

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AMDT No. 1 DEC 2012

S hower area

Bathroom area

Shower screen (shown diagrammatically) Shower screen base

Height to be 25 above the maximum retained water level or 150 above the Floor tile finished tile level of the shower floor area, whichever is the greater

Sealant on outside only

WP

Waterstop

Sealant 15 min.

Membrane support angle adhered and/or mechanically fixed to floor substrate where screed is used.

Tile bed Membrane

Where a screed is not used, the membrane to extend a minimum of 50 across the floor substrate outside the shower area instead of using a membrane support angle.

Sealant fillet (bond breaker)

(a) Enclosed shower—Membrane below tile bed

Sh ower ar ea

Ba thr o om ar ea

Shower screen (shown diagrammatically) Shower screen base

Height to be 25 above the maximum retained water level or 150 above the Floor tile finished tile level of the shower floor area, whichever is the greater

WP

Sealant on outside only Waterstop

Sealant

15 min.

Membrane support angle adhered and/or mechanically fixed to floor substrate where screed is used.

Membrane

Where a screed is not used, the membrane to extend a minimum of 50 across the floor substrate outside the shower area instead of using a membrane support angle.

Tile bed

(b) Enclosed shower—Membrane above tile bed

DIMENSIONS IN MILLIMETRES

FIGURE 3.5 (in part) TYPICAL STEPPED DOWN SHOWER CONSTRUCTION

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(c) Unenclosed shower—Membrane below tile bed

(d) Unenclosed shower—Membrane above tile bed DIMENSIONS IN MILLIMETRES

FIGURE 3.5 (in part)

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3.13.3 Hob construction

Substrate for hobs shall be constructed of masonry, concrete, corrosion-resistant metal or similar material. Autoclaved aerated concrete may be used for internal membrane systems but shall not be used for external membrane systems. Where used, autoclaved aerated concrete shall be primed before the application of the membrane. All gaps, joints and intersections of the hob substrate shall be made flush before application of the membrane. The hobs shall be adequately secured to the floor and sealed against the wall prior to applying an internal membrane. Timber shall not be used for hob construction. 3.13.4 Enclosed showers without hobs or set-downs

At the extremity of the shower area— (a)

where a shower screen is to be installed, a water stop shall be positioned so that its vertical ver tical leg will finish fini sh a mini mum of 5 mm m m above abo ve the finishe fin ished d floor flo or level lev el (see Figure 3.6); and

(b)

where the water stop intersects with a wall or is joined, the junction shall be waterproof. NOTE : For F or a typ ica l hoble h oble ss cons truc tion, tio n, see Fig ure 3.6.

NO TE: Som e sho wer scr een ext rus ions may ma y not per mit the water wa ter stop sto p ext ending end ing into int o a reb ate . A channel cha nnel section may be needed to be installed over the water stop angle with the shower screen placed on top of the channel including return panels.

FIGURE 3.6


TYPICAL HOBLESS CONSTRUCTION

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3.13.5 Unenclosed showers

This Clause sets out requirements for two types of unenclosed showers, as follows. NOTE : See S ee als o Cl aus e 3.18. 3 .18. 1.1.

(a)

Type 1 A Type 1 unenclosed shower has a device that will restrict splashing during use (see Note 1).

A water stop shall be placed under the device and across the opening of the shower of a Type 1 shower screen. NOTE S:

(b)

1

A example of a Type 1 unenclosed shower is a frameless glass shower screen.

2

It is advisable to have either the screed drained or a membrane placed on the top of the screed to prevent water retention in the screed beyond the water stop.

Type 2 A Type 2 unenclosed shower does not have a device that will restrict splashing. NOTE : A n e xam ple of a Ty pe 2 un enc losed los ed shower sho wer is a shower sho wer for peopl e w ith dis abil iti es.

The water stop of a Type 2 shower shall be a distance of a minimum of 1500 mm from the wall connection of the shower rose. For Type 1 and T ype 2 unenclosed showers, the water stop shall have the vertical leg finish flush with the finish surface of the floor and, where the water stop intersects with or joins a wall, the junction shall be waterproof. NOTE : If abso rben t typ es of stone sto ne are used use d for floorin flo orin g, they the y may dis colo ur from sho wer we r wat er out to 1500 mm water stop. Efflorescence may also form in tile joints outside the shower area, and building elements such as vanity skirtings on the floor within the water stop area may deteriorate.

3.13.6 Additional requirements for bath end walls abutting a shower

Where a bath end wall is within a shower area, it shall be treated as a shower area wall. 3.13.7 Bond breaker installation for bonded membranes

Bond breakers shall be included at all wall/floor, hob/wall junctions and at movement joints where the membrane is bonded to the substrate. Bond breakers shall be of the type compatible with the flexibility class of the membrane to be used. NOTE S:

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1

For appropriate bond breakers, see Table 3.2.

2

Typical details for bond breakers are shown in Figure 3.7.

3

Additional information on bond breakers is given in Appendix A.

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AS 3740 —201 0

TABLE 3.2 APPROPRIATE BOND BREAKER Elongation at break

Minimum bond breaker/tape width to bridge joints opening up by 5 mm

I

<60%

75 mm with backing rod

II

60% to 300%

35 mm

III

>300%

12 mm

Membrane class

NO TES : 1

Bond breakers for Class I membranes (low extens ibility) allow the mem brane to flex rather than stretch.

2

Bond breakers for Class II membranes (medium extensibility) allow the membrane to stretch. If a tape is used as a bond breaker, either the membrane will not bond to the tape or the tape will have elastic properties similar to the membrane; for example, for a Class II membrane, a 35 mm wide bond breaker/tape should be applied over a joint to accommodate the joint opening up by up to 5 mm.

3

Bond breakers for Class III membranes (high extensibility) allow the membrane to have even thickness.


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FIGURE 3.7

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TYPICAL BOND BREAKER DETAILS


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3.13.8 Vertical membrane termination

The membrane shall be applied over the floor substrate and up the vertical face of the wall— (a)

for showers with h obs and step-downs, a minimum height of 150 mm above the finished tile level of the floor or 25 mm above the maximum retained water level, whichever is the greater;

(b)

for hobless showers, a minimum height of 150 mm above the highest finished tile level of the floor within the shower area; and

(c)

for vertical flashing in shower areas, as specified in Clause 3.9.2.

3.14 MEMBRANE TO DRAINAGE CONNECTION 3.14.1 Termination to a drainage flange

For membrane drainage connections in other floors, any one of the following shall apply: (a)

A drainage flange shall be installed with the waterproofing membrane terminated at/in the drainage flange to provide a waterproof connection. NOTE S:

(b)

1

For typical membrane termination at drainage outlet, see Figure 3.8.

2

Drainage flanges may be set into the floor or fixed to the top surface of the floor substrate or tile bed.

Where a prefabricated shower tray is used, provision shall be made to drain the tile bed and provide a waterproof connection to the drain.

FIGURE 3.8

TYPICAL MEMBRANE TERMINATION AT DRAINAGE FLANGE

3.14.2 Floor waste

The floor waste shall be of sufficient height to suit the thickness of the tile and tile bed at the outlet position. The drainage flange/floor waste shall drain at the membrane level. 3.14.3 Termination to a drainage channel

The waterproof drainage shall be continuous for the membrane into the drainage outlet. Where the drainage channel does not have an integral horizontal surface of 50 mm for termination of the membrane, the membrane shall be continuous underneath the drainage channel, terminating at a recessed drainage flange. NOTE : Fo r a typ ica l ap plicat pli cation ion of a mem brane bra ne termin ter min ation ati on to a drai nag e chan c hannel nel,, s ee Fig ure 3.9.


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When the drainage channels are installed against a wall, they shall not compromise the waterproofing requirements of the wall/floor junctions.

FIGURE 3.9

TYPICAL MEMBRANE TERMINATION AT DRAINAGE CHANNEL

3.15 INSTALLATION OF AN INTERNAL MEMBRANE 3.15.1 Membrane application 3.15.1.1 General

In addition to the requirements of Clauses 3.12 and 3.13, the requirements of this Clause shall apply also for internal membranes. 3.15.1.2 Termination of membranes membranes at showers showers with with hobs

With the exception of metal angle hobs, the membrane shall be brought up over the top of the hob, down the outside face and terminate a minimum 50 mm onto the floor. NOTE : Fo r a typ ical ica l appl a pplica icatio tion, n, see Figure Fig ure 3.10. 3.10 .

For metal angle hobs, the membrane shall be terminated within 5 mm from the top of the angle, and any gap between the shower screen and the angle shall be filled with a sealant. The extent of the membrane for an internal shower tray shall be as shown in Figure 3.11(a).

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AS 3740 —201 0

NOTE: Membrane shown on substrate and above the the tile bed for diagrammatic purposes only.

FIGURE 3.10


TYPICAL HOB CONSTRUCTION—INTERNAL MEMBRANE

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FIGURE 3.11

SHOWER CONSTRUCTION

enclosed showers showers without without hobs 3.15.1.3 Termination of membranes at enclosed The membrane shall be brought to the top of the floor finish, except where it is under a shower screen where it shall terminate a minimum of 5 mm above the finished tile surface. NOTE : Fo r a typ ical ica l appl a pplica icatio tion, n, see Figure Fig ure 3.6.

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AS 3740 —201 0

3.16 INSTALLATION OF AN EXTERNAL MEMBRANE 3.16.1 Membrane application 3.16.1.1 General

Where the membrane is fabricated from a flexible material, the top edges shall be fixed to the wall. Fixing penetrations shall be a minimum of 100 mm above the finished tile level of the shower area. All fixings shall be compatible with the membrane and shall be non-corrosive. 3.16.1.2 Showers with hobs

The hob shall be included within the finished size of the shower membrane and the membrane shall finish at the underside of the tile that forms the top of the hob. NOTE : Typic Ty pical al hob constr con struct uct ion for an extern ext ernal al mem bra ne is shown sho wn in Fig ure 3.12. 3.12 .

The extent of the membrane for an external shower tray shall be as shown in Figure 3.11.

FIGURE 3.12

TYPICAL HOB CONSTRUCTION—EXTERNAL (PREFORMED) MEMBRANE

3.16.2 Base termination of vertical flashing

Vertical flashings in internal corners shall extend into the external membrane by a minimum of 25 mm. 3.16.3 Drainage riser connection 3.16.3.1 Preformed trays

The drainage riser shall be connected to the tray with a waterproof joint. 3.16.3.2 Made in situ shower trays

A drainage flange shall be installed with the waterproofing membrane terminating in the drainage flange at not less than 20 mm. The membrane shall be able to form a permanent seal to the drainage flange. NOTE : Fo r a typ ical ica l m emb rane ran e e xtensi xte nsion, on, see Fig ure 3.8.


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3.17 DOORJAMBS AND ARCHITRAVES

Where the bottom of doorjambs and architraves do not finish above the floor tiling, the portion of the doorframes and architraves below the floor tiling shall be waterproofed to provide a continuous seal between the perimeter flashing and the water stop. NOTE S: 1

For typical door detail, see Figure 3.3.

2

Where possible, the doorjambs and architraves should be i nstalled above the floor tiling.

3.18 SHOWER SCREEN 3.18.1 General 3.18.1.1 Unenclosed shower screen

An unenclosed shower screen consists of— (a)

a frameless shower screen, unless the shower screen is fitted with seals and deflectors, all of which control the spread of water from the shower area; or

(b)

a shower screen less than 900 mm long o ver a bath; or

(c)

a shower area where a curtain is hung on a rod.

Unenclosed shower areas are not suitable for use directly adjacent to doorways unless the doorway is protected against water exiting through the doorway. Encl osed shower sho wer screen scre en 3.18.1.2 Enclosed For an enclosed shower, the shower screen shall be designed and installed to prevent the spread of water from the shower enclosure. An enclosed shower screen consists of— (a)

a fully framed (including sill) shower screen where the water from the shower rose is controlled to within the shower area; or

(b)

a partly or semi frameless shower screen where the vertical edges of the unframed panels are fitted with suitable seals or where panels overlap o ne another (and where a sill is included); or

(c)

a frameless shower screen that is fitted with seals and deflectors, to control the spread of water within the shower area.

NOTE : Where Wh ere a sho wer screen scr een is cla ssi fied fie d as une nclo sed, the wat er stop sto p and the positi pos itioni oning ng of the waterproofing of the floor should be as specified in Clause 3.13.5.

3.18.2 Enclosed shower screen placement 3.18.2.1 Showers with hobs

The shower screen shall be installed so as to ensure it is— (a)

flush with the shower area side of the hob;

(b)

overhanging in to the shower area; or

(c)

inside the hob.

NOTE : A sel f-drai f-d rai ning nin g s ub-s ill is consid con sidered ered to be p art of the show er screen scr een..

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3.18.2.2

AS 3740 —201 0

Showers with step-downs

The shower screen shall be installed so as to ensure it is— (a)

flush with the finished vertical surface of the step-down

(b)

overhanging into the shower area; or

(c)

inside the step-down of the shower area.

3.18.2.3

Showers without hobs or step-downs

The shower screen shall incorporate or be mounted on an inverted channel, and positioned over the top of the water stop that defines the shower area. NOTE : Fo r a typ ica l hoble h oble ss cons truc tion, tio n, see Figure Fi gure 3.6. 3.18.2.4

Bath end end walls and nib walls abutting abutting a shower

The shower screen shall be positioned so that the bottom edge within the shower area is either flush with the outside edge of the bath or overhanging into the shower area. NOTE : A sel f-dr aining ain ing sub-si sub -si ll is consid con sidered ered to be p art of the shower sho wer scre en.


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APPENDIX A DESIGN CONSIDERATIONS IN WET-AREA WATERPROOFING

(Informative) A1 SCOPE

This Appendix provides information that should be considered when designing waterproofing systems for wet areas in domestic buildings and includes guidelines for dealing with the degree of risk, and the types of materials used and their locations in the construction. A2 LEAKAGE THROUGH FINISHES

Water may penetrate wall and floor finishes in wet areas, depending on the frequency, the intensity and the length of time these surfaces are exposed to water; if not intercepted, water may damage the moisture-sensitive materials lying beneath, and sometimes reach adjoining rooms and their finishes. Consequently, careful attention should be paid to the design and installation of all materials, components and systems to prevent damage by water. Water penetration mainly occurs at joints. Grouted joints will often shrink, producing cracks that allow water to pass through. At floor and wall junctions, these cracks can be caused or enlarged by movement of the structure, substrate or finishes. A3 MOVEMENT AND WATERPROOFING A3.1 General

Movement in the wall and floor structure is often caused by contraction, expansion or settlement. Users of this Standard should be aware of the need for waterproofing materials or systems to accommodate the expected movement of the structure. A3.2 Structure movement A3.2.1 Frame movement

Potential movement of corner studs is restricted if the studs are fastened to intermediate blocking pieces. Where the framing is constructed of metal or seasoned timber, blocking is generally a provision to restrict structural deflection. Unseasoned timber requires additional consideration for movement and its subsequent effects upon the waterproofing system. A3.2.2 Masonry movement

Masonry products such as clay-based materials, cement-based materials and autoclaved aerated materials may be subject to specific movement characteristics depending on the material used. These products also require consideration of movement and its subsequent effects upon the waterproofing system. A3.2.3 Panel movement

Panel products are also subject to movement, particularly at joints. Such products also require consideration of movement and its subsequent effects upon the waterproofing system.

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A3.3 Wall linings under tiles in shower shower areas

While it is considered that the faces of the nominated linings are impervious enough to shield wall framing against damage from water that penetrates tiled finishes in wet areas, the joints between lining sheets and their junctions with other materials may require special attention to intercept or stop the natural path of water through them. Of major concern are the vertical corner joints and the perimeter joints where the potential for shrinkage and structural movement of the framing is greatest. Therefore, vertical corner joints join ts s hould houl d be b e provi pr ovided ded with wit h fl ashing ashi ng angles ang les and sealant seal ant for surface sur face finishe fin ishes. s. A3.4 Prefinished wall panels

Vertical joints between panels and their horizontal junctions with other materials should be carefully considered, as the panels are the only barrier between the water and the framing beneath. All joints between panels should be either flashed or waterproofed with a sealant, and the bottoms of panels installed to overlap adjoining materials. A3.5 Floors A3.5.1 General

Waterproof barriers are required to prevent downward or sideways movement of water into adjoining construction or rooms. Water naturally penetrates tiled floor finishes more readily than wall finishes. Where a tile bed is used, a waterproof membrane may be installed above or below the tile bed. Where a membrane is installed above a tile bed, it is essential that the tile adhesive be compatible with the membrane. Where the membrane is under the tile bed, the tile bed tends to become a reservoir of moisture. A drainage system should be provided within the tile bed, over an in situ membrane. This allows the reservoir of moisture to discharge into the waste fitting or pipe (see Figure 3.8). A3.5.2 General requirements of barriers

In order to m aintain waterproofing integrity, trays or flashing angles should be installed in a manner that allows for the expected movements of the supporting structure. In situ membranes and flashings should be able to cover floor-to-wall and wall-to-wall joints without tearing or breaking under the forces exerted on them when movement occurs in the adjacent elements to which they are fixed. For framed construction, prefabricated flashing angles should be adhered only to the floor, allowing the sides of the vertical legs to accommodate the differential movement between walls and floors. barriers—Properties and installation A3.5.3 In situ barriers—Properties Some of the materials specified for in situ membranes or flashings are not considered sufficiently elastic to stretch without tearing, or flexible enough to bend without breaking when subjected to joint movement. Therefore, such barriers should not be applied directly across the joint, and should be completely bonded to both adjacent surfaces. The correct approach is to first install a ‘bond-breaker’ at the wall/floor junction. This bond-breaker may consist of any of the following depending on the class of the membrane: (a)

A flexible closed cell foam-backing rod combined with a suitable bond-breaker tape.

(b)

A suitable sealant.

(c)

Bond-breaker tape.

The method used should be directly related to the type of membrane installed. More rigid membrane and flashing materials, which bend rather than stretch, are better suited for use with a backing rod and bond-breaker tape (see Figure 3.7). ww w.s tan dard s.o rg. au

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A3.5.4 Set-downs

Vertical edges of the set-downs should align flush with the wall substrate to avoid creating voids, vo ids, cavities cav ities or protru pro trusion sions. s. They The y should sho uld be repaire repa ired d prior prio r to installat inst allation ion of a waterproofing system, as they are the cause of many w aterproofing problems. A3.5.5 Tiles within shower area

Small dimension tiles used in shower areas enable the tiler to achieve the necessary fall to the waste as the size of the tiles increase adequate falls become more difficult to achieve.

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APPENDIX B FALLS IN FLOOR FINISHES

(Informative) B1 GENERAL

The primary consideration for falls in floor finishes is to ensure water does not remain on the finished floor in a manner that can adversely affect the health or amenity of the occupants or deteriorate building elements. Falls in floor finishes should ensure water exits the area at the floor waste or doorway if that is the designed exit point (e.g., laundry door to exterior). Water should not pond on the floor, with the exception of residual water remaining due to surface tension. B2 FACTORS AFFECTING FALLS

The ratio of fall achieved in a floor may vary depending upon the— (a)

finished height requirements at doorways;

(b)

height of fixtures or fittings;

(c)

dimensions of the tiles used, adequate falls become more difficult to achieve as the size of the tiles used increases;

(d)

area of the floor to be drained; and

(e)

requirements of persons with disabilities.

B3 FALL RATIOS

Clause 3.4 specifies a fall ratio of 1:100 in shower areas. Where falls flatter than 1:100 are proposed, the effectiveness of the floor drainage should be confirmed to ensure the primary consideration given in Paragraph B1 has been met. B4 DIAGONAL CUTTING OF TILES

Tiles may require diagonal cutting in the area around the waste to achieve the required falls, sufficient drainage and to ensure lipping is kept within the guidelines of AS 3958.1.


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Appendix C (new) Add new

Appendix C, as follows:

2012

APPENDIX C EXTENT OF WATERPROOFING

(Informative) This Appendix is based on Table F1.7 (BCA, Volume 1) and Table 3.8.1.1 (BCA, Volume 2) of the National Construction Code (NCCA). Table C1 is reproduced from Table F1.7, which lists the NCC requirements for waterproofing and water resistance for building elements in wet areas. Figures C1 and C4 provid pro videe a diagra dia gramm mmati aticc repres rep resent entati ation on of the extent ext ent of waterp wat erproo roofin fing g stipul sti pulate ated d in Tables F1.7 and 3.8.1.1 of the NCC. Where the shower shown in the Figures is not enclosed, the wet area is to be taken as 1500 mm from the shower connection. NOTE: NOTE : User U ser of t his Stan dard shoul d refer r efer to the current cur rent edition edi tion of t he NCC for any changes chan ges to the Tables.

Waterproof vessel/wall j u n c t i o n 150 mm

WR

(a) Vessel abutting wall

Waterproof bath/wall j u n c t i o n

150 mm

WR

(b) Wall/bath junctions without shower

FIGURE C4 BATH AND VESSEL VESSEL ABUTTING WALL—AREAS TO BE PROTECTED

Waterproof corner to 1800 high from finished floor level, minimum width of 40 either side of the junction

40 Shower rose

Edge of shower screen

WP

1800

Shower screen WR

Height as per Table C1 (i) Plan view

Waterproof (ii) Side view (a) Enclosed shower 40

1500 1500

1800

WP

Minimum extent of waterproofing

Height as per Table C1

WR

(i) Plan view Waterproof (ii) Side view

( b ) U n e n c l o s e d s h o w e r s — C o n c r e te te a n d c o m p r e s s e d f i b r e c e m e n t s h e e t f l o o r s

NOTE: All floor waterproofing to terminate at a waterstop. DIMENSIONS IN MILLIMETRES

FIGURE C1 EXTENT OF THE TREATMENT FOR SHOWER AREAS—CONCRETE AND COMPRESSED FIBRE-CEMENT SHEET FLOORS

Waterproof corner to 1800 from finished floor level, width of 40 either side of the junction

Optional shower panel

(i) Plan view

40 1500 900 min.

Waterproof corner to 1800 from finished floor level, width of 40 either side of the junction Shower panel sealed at all junctions

Shower screen

Water-resistant walls to 1800 from finished floor level

WR

WR

Seal tap or mixer, shower rose and bath spout penetrations. Waterproof junction width of 40 either side of the ju n c t i o n

Waterproof bath/wall junction

Waterproof junction

WR WR 150

Waterproof j u n c t i o n

WP Waterproof bath lip/tile joint (ii) Isometric view

(a) 900 mm shower panel


FIGURE C2 (in part) UNENCLOSED SHOWERS ABOVE BATHS—AREA PROTECTED FOR CONCRETE AND COMPRESSED FIBRE-CEMENT SHEET FLOORING

1500

Waterproof corner to 1800 from finished floor level, width of 40 either side of the junction 200 min. 1500 Measured from the shower connection at the wall and terminating at a waterstop

Shower panel

Required floor waste (i) Plan view

40

200 min.

1500


Shower screen

1500 measured from the shower connection at the wall


WR

WR

Seal tap or mixer, shower rose and bath spout penetrations Waterproof junction width of 40 either side of the junction


Waterproof junction to 1500 from the shower connection at the wall and 25 above finished floor level

WR WR 150 WP

Waterproof j u nc ti o n

Required floor waste Waterproof bath lip/tile joint

WP

(ii) Isometric view

Waterproof to 1500 from shower connection at wall and grade to a floor waste and terminate with a waterstop.

NOTE: All floor waterproofing to terminate at a waterstop.

(b) Shower panel less than 900 mm



Waterproof corner to 1800 Waterproof from finished floor level, width of 40 either side of the junction

Measured from the shower connection at the wall

1500

Required floor waste

(i) Plan view

Waterproof corner to 1800 Waterproof from finished floor level, width of 40 either side of the junction

40

1500



Shower connection WR

Seal tap or mixer, shower rose and bath spout penetrations

WR

Waterproof junction width of 40 either side of the junction


Waterproof junction to 1500 from the shower connection at the wall and mm above finished floor level

WR WR 150 WP

Waterproof ju nc ti on

Required floor waste

WP Waterproof bath lip/tile joint (ii) Isometric view

Waterproof to a minimum of 1500 from shower connection at wall and grade to a floor waste and terminate with a waterstop.


(c) No shower panel




Shower panel

Waterproof entire floor

(i) Plan view 40 1500


900 min.

Shower panel sealed at all junctions

Shower screen


WR

Seal tap or mixer, shower rose and bath spout penetrations

WR



Waterproof junction to the wall and 25 above finished floor level WR 150 Waterproof j un c ti o n jun

Waterproof bath lip/tile joint

WP


(ii) Isometric view

(a) 900 mm shower panel


FIGURE C3 (in part) UNENCLOSED SHOWERS ABOVE BATHS—AREA PROTECTED FOR TIMBER FLOORS INCLUDING PARTICLEBOARD, PLYWOOD AND OTHER FLOOR MATERIALS

Waterproof corner to 1800 from finished floor level, width of 40 either side of the junction Shower connection

1500

Shower screen 200 min.

Extent of waterstop where applicable

Required floor waste Waterproof entire floor (i) Plan view

200 min.

40 1500



Shower connection Shower screen

WR

Seal tap or m ixer, shower rose and bath spout penetrations

WR



Waterproof junction to the wall and 25 above finished floor level WR 150

Waterproof j u n c t i o n

WR Required floor waste WP Extent of waterstop where applicable

Waterproof bath lip /tile joint


(ii) Isometric view


(b) Shower panel less than 900 mm




1500

Shower connection Extent of waterstop where applicable

1500

1500 Required floor waste Waterproof entire floor (i) Plan view

1500


40


W a t e r - re re s i s t a n t w a l l s t o 1800 from finished floor level

Shower connection WR

Seal tap o r mixer, shower rose and bath spout penetrations

WR



Waterproof junction to the wall and 25 above finished floor level

WR WR 150

Required floor waste Waterproof ju nc t io n

WP

15 0 Extent of waterstop where applicable

1 50 Waterproof bath lip/tile joint

Waterproof entire floor (ii) Isometric view


(c) No shower panel



TABLE C1 WATERPROOFING AND WATER RESISTANCE REQUIREMENTS FOR BUILDING ELEMENTS IN WET AREAS Vessels or area where the fixture is installed

Floors and horizontal surfaces

Walls

Wall junctions and joint s

Wall/floor junc tions

Penetrations

Shower area (enclosed and unenclosed)

With hob

(a)

Waterproof all walls in shower area to a height the greater of— (i)

With With step-dow step-down n

Waterproof floor in shower area (including any hob or step-down)

Without hob or stepdown

(ii) (ii) (b)

With preformed shower base

N/A

not less than 150 mm above floor substrate; or not less less than 25 mm above maximum retained water level; and

Waterproof wall junc tions withi n shower area

Waterproof wall/floor junc tion s wit hin shower area

Waterproof penetrations in shower area

Waterproof wall junc tions withi n shower area

Waterproof wall/floor junc tion s wit hin shower area

Waterproof penetrations in shower area

Water resistant walls in shower area to not less than 1800 mm above finished floor level of the shower

Water-resistant walls in shower area to not less than 1800 mm above finished floor level of the shower

Area outside shower area

For concrete and compressed fibre-cement sheet flooring For timber floors, including particleboard, plywood and other timber-based flooring materials

Water-resistant floor of the room N/A

N/A

Waterproof floor of the room

Waterproof wall/floor junc tion s

N/A

( continued )

TABLE C1 (continued ) Vessels or area where the fixture is installed


Walls



Penetrations

Water-resistant wall/floor junct ions for the extent of the vessel

Waterproof tap and spout penetrations where they occur in horizontal surfaces

N/A

Waterproof tap and spout penetrations where they occur in horiziontal surfaces

N/A

Waterproof tap and spout penetrations where they occur in surfaces required to be waterproof or water resistant

Area adjacent to baths and spas (see Note 1)

For concrete and compressed fibre-cement sheet flooring

Water-resistant floor of the room

For timber floors, including particleboard, plywood and other timber-based flooring materials


(b)

Water-resistant all exposed surfaces below vessel lip

Inserted baths and spas

(a)

(a)

Waterproof to not less than 150 mm above lip of bath or spa

Waterproof shelf area, incorporating waterstop under the bath lip

(a)

Water-resistant to a height of not less than 150 mm above the vessel, for the extent of the vessel, where the vessel is within 75 mm of a wall

Water-resistant junct ions withi n 150 mm above a vessel for the extent of the vessel

(a)

and

Waterproof junc tions withi n 150 mm above bath or spa and

(b)

Walls adjoining other vessel (e.g. sink, basin or laundry tub)

Laundries and WCs

No requirement under bath

N/A


(b)



N/A

(b)


Waterproof wall junc tions wher e a vessel is fixed to a wall

N/A


Waterproof penetrations where they occur in surfaces required to be waterproof ( continued )



Walls



Penetrations

Water-resistant wall/floor junct ions for the extent of the vessel

Waterproof tap and spout penetrations where they occur in horizontal surfaces

N/A

Waterproof tap and spout penetrations where they occur in horiziontal surfaces

N/A

Waterproof tap and spout penetrations where they occur in surfaces required to be waterproof or water resistant

Area adjacent to baths and spas (see Note 1)

For concrete and compressed fibre-cement sheet flooring


For timber floors, including particleboard, plywood and other timber-based flooring materials


(b)

Water-resistant all exposed surfaces below vessel lip

Inserted baths and spas

(a)

(a)

Waterproof to not less than 150 mm above lip of bath or spa

Waterproof shelf area, incorporating waterstop under the bath lip

(a)


Water-resistant junct ions withi n 150 mm above a vessel for the extent of the vessel

(a)

and

Waterproof junc tions withi n 150 mm above bath or spa and

(b)

Walls adjoining other vessel (e.g. sink, basin or laundry tub)

Laundries and WCs


(b)


N/A



N/A

(b)


Waterproof wall junc tions wher e a vessel is fixed to a wall

N/A


Waterproof penetrations where they occur in surfaces required to be waterproof ( continued )



Walls


Bathrooms and laundries required to provide a floor waste


N/A

N/A



Penetrations

Waterproof penetrations where they occur through the floor

LEGEND: N/A = no t app licab le NOTES : 1

Where a shower is above a bath or spa, use requirements for shower.

2

This Table has been reproduced from the National Construction Code (NCC), (BCA, Volume One—2012, Table F1.7), with the permission of the Australian Building Codes Board (ABCB).

3

Users of the Standard should check that the NCC Table has not changed before using its reproduction.

4

Where a penetration passes through waterproof or water-resistant construction, the penetration should be made waterproof.



Walls


Bathrooms and laundries required to provide a floor waste


N/A

N/A



Penetrations

Waterproof penetrations where they occur through the floor

LEGEND: N/A = no t app licab le NOTES : 1

Where a shower is above a bath or spa, use requirements for shower.

2

This Table has been reproduced from the National Construction Code (NCC), (BCA, Volume One—2012, Table F1.7), with the permission of the Australian Building Codes Board (ABCB).

3

Users of the Standard should check that the NCC Table has not changed before using its reproduction.

4

Where a penetration passes through waterproof or water-resistant construction, the penetration should be made waterproof.

AS 3740 —201 0

38

BIBLIOGRAPHY

AS 3958 AS 3958.1

Ceramic tiles Part 1: Guide to the installation of ceramic tiles

HB 161

Guide to Plastering

AS 3740 —201 0

38

BIBLIOGRAPHY

AS 3958 AS 3958.1

Ceramic tiles Part 1: Guide to the installation of ceramic tiles

HB 161

Guide to Plastering

39

NOT ES

AS 3740 —201 0

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ISBN 978 0 7337 9703 3

AS 3740-2010 (with Amdt 1 2012) Waterproofing of Domestic Wet Areas

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