QUANTITIES OF MATERIALS 

 Therefore, volume of compacted plaster = 40 X f X ^ 



283 



= %f- cubic yards. 



From the table on page 135 we find that 1 cubic yard compact 

 plastic, 1 : 3 mortar requires 2*37 barrels cement, and 100 cubic yard 

 sand; hence — 



Cement required for -^ cubic yards mortar = 2*37 X 5 ^ 



= 5*27 barrels 



or say 5^ barrels, or 11 bags. 

 Sand required for 2fi cubic yards mortar = -J 1 = 2 5 cubic yards. 



If coarse, unscreened sand be used for making mortar, the following 

 table should be employed for the purpose of estimating the quantities 

 of materials required. 



Mateeials fob 1 Cubic Yabd Compact Plastic Mortar, made 

 with Coarse Sand (approximate). 



Cement required for laying Bricks. — One cubic foot (90 lbs.) of loose 

 Portland cement to three of sand will lay about 212 bricks with f" joints, 

 and 317 bricks with J" joints. 



Quantities of Timber, Corrugated Iron, etc. — The taking out of these 

 quantities is mainly a matter of making measurements from the drawings. 



If no drawings exist, however, the estimates must be prepared from 

 the known dimensions of the proposed building under consideration ; in 

 this case one is much more apt to forget items than when proper drawings 

 are available. 



In estimating quantities of timber, allowance should be made for 

 the fact that the ends of boards and deals often contain shakes which 

 run into the wood for some distance, and that it may be desirable to 

 cut these ends off. 



In estimating corrugated iron, allowance should be made for the 

 necessary overlaps, and for projecting eaves, etc. In ordering this 

 material a good brand should be specified. 



