thickness to project at least 4 inches above the ground. 

 Wood blocks should never be used for footings under founda- 

 tion posts. 



(b) If substantial stones nre not available, provide 

 a masonry or concrete footing. For masonry use only hard 

 stones, preferably flat ones. All should be carefully im- 

 bedded on their broadest faces in mortar of 1 part cement 

 and parts coarse, clean, sharp sand. Each layer should 

 be well filled and flushed up on both sides and firmly 

 bonded together. The tops should be made level to receive 

 the underpinning. See Table No. C-4. 



(c) Large stones of sufficient thickness to raise 



the sill to a height of at least 12 inches above the ground. 



(d) Blocks of masonry or concrete at least 12 inches 

 high, 10 inches wide on top and 16 inches square at the 

 bottom. The top of concrete and masonry blocks should be 

 made level to receive the sills. See Concrete Section and 

 Table No. C-4. 



(e) If water and sever pipes are to be placed under 

 a building, foundation blocks or underpinning must be at 

 least 24 inches high. 



MATERIALS. 



Al}. structural materials should conform as closely 

 as possible to the specifications given in the builder's 

 list and lumber order list. That minor deviations must 

 sometimes be made is recognized as unavoidable. 



SILLS. 



Should preferably be of cedar 1 or redwood. Douglas 

 fir may be used as a second choice* 



Set rectangular sills with narrow edge up* 



Sills at corner should be halved together*- When 

 two or more pieces are necessary to form the total length 

 of sill a splice should be made on the foundation supports, 



-16- 



