DAMP COUESE 23 



upper course should be as far removed as possible from occupying 

 positions vertically above the joints in the lower course. This is fully 

 explained in the discussion on "bond" contained in the next chapter. 

 As there mentioned, frequent " headers " should be inserted. The 

 preceding remarks apply to succeeding courses, in the event of the 

 footings being deep. 



Trenches which are to receive stone or brick footings should be 

 excavated wide enough to leave at least a 4-inch space on each side 

 of the footing, in order to allow working room for the builder. For 

 concrete footings, however, the trenches should be excavated to the 

 exact width required, and entirely filled with concrete. Spaces left 

 between brick or stone footings and the sides of the foundation trenches, 

 should be rammed in with earth after the footings have been completed, 

 care being exercised not to weaken the footings by too violent 

 ramming. 



The footing should extend to a height of at least 9 inches above 

 the ground surface, at the highest point of the latter. The upper surface 

 of the footing should be finished flat and level to receive the damp course. 



Damp Course. — The function of the damp course is to prevent 

 damp from rising into the walls above ground. 



It usually consists of asphaltic or bituminous felt, which can be 

 purchased from suppliers of building material, under the name of 

 " damp-course felt." The upper surface of the footing should be covered 

 by a continuous layer of the felt, any junctions between different 

 lengths of felt being formed by overlapping the two lengths to an 

 extent of at least 6 inches. 



Another form of damp course is one which may be applied in a 

 semi-liquid state. It is prepared by boiling tar, and adding sand till 

 the mixture assumes the consistency of thick porridge. The addition 

 of a little pitch is advantageous, as it causes the mixture to solidify 

 better, thus making it less liable to be squeezed out by the weight of 

 the wall on top of it. The mixture should be applied hot to the top 

 of the footings, with the aid of a trowel, to a thickness of £ to § inch. 

 About two days after its application this type of damp course will be 

 solid enough to allow of the walls above it being commenced. 



Examples of masonry footings are shown in many of the illustrations 

 in this book. It will be noticed that the outer top edge of the footing 

 is bevelled off, or " weathered " as it is called, so as to shed rain-water. 



