Bridging is Important 143 



to the boards of the first floor, or parallel with 

 the joists. A little reflection will reveal the 

 reasons for all this. 



Joists should be bridged. Fig. 55 shows the 

 more common method of bridging. The joists 



Fig. 54. The rough floor laid before the studding is erected. 



may be 2x8 in small, inexpensive houses, and 

 2x10 or 2x12 in large ones, bridged once in a 

 12 -foot span, twice in a 16-, and three times in 

 an 18- or 20 -foot span. The bridging is of the 

 utmost importance and should never be omitted, 

 as it serves to strengthen the floor joints and 

 prevents the disagreeable trembling of the floors 

 so annoying in many of the older houses. 



The studding for a balloon frame is either 



