Contents. PART C Chapter 4. Estimating PART C:CHAPTER 4. Estimating 4.1 BASIS OF TABLE

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1 PART C Chapter 4 This chapter provides guidance on calculating the quantities of masonry units, mortar and grout for particular projects. Contents 4.1 BASIS OF TABLE 4.2 WORKED EXAMPLE

2 4.1 BASIS OF TABLE There are slight variations in face shell widths, core tapers, core dimensions and web rebates of hollow concrete blocks throughout Australia. When calculating mortar and grout quantities, exact dimensions should be sought from the manufacturer and adjustments should be made to account for the peculiarities of the particular units. Numbers of blocks When calculating the number of blocks required for a particular wall area, it is necessary to know the effective face area of one masonry unit and the mortar associated with it. Since mortar joints are 10 thick, the effective face area is given by (length of unit + 10 ) x (height of unit + 10 ) Mortar The mortar volume tables are based on the following assumptions: 90-- and 110--wide units are fully bedded (considered to be solid or cored units) and have full perpendicular joints. All joints are 10 thick and an allowance of 10% for frogs, cores and wastage. If a higher wastage is expected, the estimator should make the appropriate allowance and 190--wide units are face-shell bedded (considered as hollow units) and have face-shell bedded perpendicular joints. Minimum face shell widths of 25 and 30 have been allowed for 140- and 190- units respectively. All joints are 10 thick and an allowance of 50% for overflow into cores and for wastage. If a higher wastage is expected, the estimator should make the appropriate allowance. Grout The tabulated grout quantities are based on the percentage solid for the most coon core sizes, as set out below. An allowance of 10% for wastage has also been included. Width of unit Percentage solid () (%) (cannot be grouted) 110 (cannot be grouted) Density Of Materials The following densities can be used to calculate wall mass, for purposes of determining vertical gravity loads on supporting structures, earthquake loads and sound attenuation. Density Material (kg/m 3 ) Dense-weight concrete masonry units 2180 Lightweight concrete masonry units 1800 Mortar 2 Grout 2400 Plasterboard 800 Table 4.1 Table 4.1 sets out block, mortar and grout quantities as described on this page. To calculate the quantities in a project, use the Sheet.

3 Table 4.1 Block, Mortar and Grout Quantities Number of Volume of mortar Volume of grout (m 3 ) per Unit dimensions units per (m 3 ) per m 2 0 m 2 0 m 2 0 Length Height Width % m 2 m 2 0 of wall units of wall units of wall units () () () solid of wall of wall units Every core filled 800 crs 2000 crs Sheet PART C:CHAPTER 3 Detailing

4 Sheet [Print Page] CALCULATION OF QUANTITY OF MORTAR REQUIRED CALCULATION OF NUMBER OF UNITS REQUIRED Gross area of wall Deduct openings Net area of wall From Table 4.1 Deduct corners: nxhxt 0 Net masonry area Face dimensions of units (length x height) n Number of corners H Height of wall (m) t Thickness of wall () Volume of mortar per of wall m3/ m3 CALCULATION OF QUANTITY OF GROUT REQUIRED Spacing of grouted cores Dimensions of units (length x height x width) Total number of units Deduct special units: Number of corner units Number of lintel units Number of sash/jamb units Number of control joint units Number of other units Total volume of mortar required Number of units per of wall From Table 4.1 Net area of masonry Dimensions of units (length x height x width) Full Half Three-quarter From Table 4.1 Volume of grout per of wall m3/ m3 Total volume of grout required Total number of special units Total deduction in stretcher units Net number of stretcher units PART C:CHAPTER 3 Detailing QUIT

5 4.2 WORKED EXAMPLE Worked Example [Page 1 of 2] INTRODUCTION The purpose of this worked example is to demonstrate the derivation of Table 4.1 and to enable similar calculations to be carried out. AIM To find the number of blocks, volume of mortar and volume of grout required for the wall illustrated blocks Grouted 800 centres 200 DATA Face area of wall: 200 Aw 3.6 x Percentage solid: p Unit length: Lu 390 Thickness of mortar: tm 10 Unit height: Hu 190 Grouted core spacing: S 800 Unit width: Wu 140 Face shell width: ts 25 55% 0.55 QUIT

6 Worked Example [Page 2 of 2] CALCULATIONS Number of units per of wall: N,000,000 (L u + t m ) (H u + t m ),000,000 ( ) ( ) 1250 units per of wall Number of units in wall: N N A w 1250 x 151 N 1890 units say Volume of mortar per m 2 of wall, allowing for 50% wastage: NOTE: When ordering, make allowance for halves, fittings and breakage N V m (L u + H u + t m ) t m 2 t s x 1.5 1,000,000, ( ) 10 x 2 x 25 x 1.5 1,000,000, m3 per of wall Volume of grout per of wall, allowing for 10% wastage: V g N (1 - p) L u W u (H u + t m ) x 1,000,000,000 S 1250(1-0.55) x 390 x 140 x ( ) x x 1,000,000, x m 3 per m 2 of wall Volume of grout in wall: V g A V w g 1.7 x m3 Volume of mortar in wall: A V m V w m 0.55 x m3