CHB WALL ESTIMATE.docx

i just found a bug in the mortar (cement and sand) computation of my estimate for a 1 sqm of wall using 4" CHB while i was reiewing the formula last night! the !#$% cubic meter of sand and !$1$$ bag of cement from my preious posting replies was &'*! the 1%!# 4" CHB for 1 sqm of wall is still C''+C, !!!

below is the correct computation for the estimate i did- after chec.ing all my old notes from our house construction !!! apologi/e for the wrong info before !!!

4" CHB dimension !!! 04mm 2 H%mm 2 &1mm (appro2 13" 2 " 2 4")

dimension of 1 caity in a 4" CHB !!! #mm 2 5mm 2 16mm

i hae remoe the plastering and rebar (% pcs of 1m lenght 5mm deformed rebar for 1 sqm of wall) in the estimation of a 1 sqm of wall as it ma.es more sense to compute the estimate of these items separately on a per wall basis based on the house7bldg plan!

to get the amount of mortar required for a 1 sqm wall- first we need to estimate the area7olume in which the mortar will be put! these are8 9 a 4" CHB normally has $ caities each measuring an area of appro2 5mm 2 #mm 2 16mm! 9 at the sides of a 4" CHB- you can also see a half9circle (or half9square) groe! if you set % CHB in a line with a 17%" clearance between the % CHB- the area for the mortar can also be computed as appro2imately 1 caity too! since each 1m (1mm) length of  wall will require about %!# CHB- this means another $ caities for the %!# CHBs in a row! 9 so total caities (ertical area) per row will be 3 (for the % CHB) : 1!# (for the 17% CHB) : $ (for the %!# CHB per row)  1!# caities! 9 the height of a CHB is appro2 %mm- add the 17%" (1%mm) mortar height between rows- you hae appro2 a %1%mm height! in a 1m high wall- you will then need appro2 # rows (1mm 7 %1%mm  4!6%) of CHB! 9 the area for the mortar in between rows (hori/ontal area) of CHB will be about 17%"

(1%mm) high with a lenght of 1mm (1m) and a width of 1mm (4")

using the same formula for computing concrete with a mi2 ratio of 1838 (cement8sand8grael) for mortar- you can then compute the total olume of concrete needed for the area of 1 sqm wall of 4" CHB !!! 9 for each caity (ertical area)- the area7olume is !!! ;<(5=#=16) 7 1> 7 1?  ! cubic meter = 1!# (number of caities in a row)  ! cubic meter of concrete 9 for each row (hori/ontal area)- the area7olume is !!! ;<(1=1=1%) 7 1> 7 1?  !1% cubic meter = # (number of rows)  !3 cubic meter of concrete 9 total olume  ! : !3  !14 cubic meter of concrete for a 1 sqm wall

haing the concrete olume- we can then compute for the cement and sand using a mi2 ratio of 1838 9 grael or aggregate is not needed for mortar !!!

so- to get the amount of cement needed for a !14 cubic meters of concrete the formula is !!! (olume = ratio of cement) 7 mi2ture total ratio !!! (!14 = 1) 7 6  !1476  !% cubic meter of cement !!!

so- to get the amount of sand needed for a !14 cubic meters of concrete the formula is !!! (olume = ratio of sand) 7 mi2ture total ratio !!! (!14 = 3) 7 6  !476  !1% cubic meter of sand !!!

in summary !!! !14 cubic meters of concrete with a ratio of 1838 will require !!! !% of cement !1% of sand 99999999 !14 cubic meters of concrete (total) !!!

to conert the amount of cement into bags of cement !!! just multiply the cement in cubic meters by $#!$1 !!! !% = $#!$1  !6 bags of cement !!!

cheers !!!

Boo@