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Yearbook^ of Agriculture 1949 



should be covered with roofing paper 

 and several inches of gravel. 



At the building site, panels can be 

 inspected for good workmanship to see 

 if they are true and well-made, with 

 continuous glue joints between frame- 

 work and facings. How well they fit 

 together while the walls, floors, ceil- 

 ings, partitions, and roof are being as- 

 sembled is a clue to their manufacture. 

 Do panels join well together at room 

 corners and at the joints where wall, 

 floor, and ceiling meet? Small gaps 

 here are to be expected and can be 

 hidden with molding and other trim, 

 but the finished job should be neat. 



In most modern houses, both pre- 

 fabricated and conventional, there is 

 an unfinished attic space between ceil- 

 ing and pitched roof. Insulation is laid 

 over the ceiling. The attic space is an- 

 other source of danger from moisture 

 vapor. A vapor barrier should be laid 

 under the insulation. The attic should 

 also be ventilated; this is usually done 

 by means of louvered openings in both 

 gable ends to permit air to pass through 

 the attic space. The openings should be 

 ample in size; they are more likely to 

 be too small than too large. 



An inspection of the exterior of the 

 finished house can be helpful. In par- 

 ticular, all the exterior joints between 

 panels, especially the horizontal joints, 

 should be especially well made and 

 protected with metal flashing, drip 

 caps over windows and doors, and 



similar devices for blocking the pene- 

 tration of rain water. A roof with a 

 good overhang has advantages. 



The critical buyer may want to 

 check on several other details, but he 

 should bear in mind that the basic fac- 

 tors are good materials, and good work- 

 manship, and good structural design. 

 Each depends on the others and com- 

 plements them. In building with wood, 

 the designer keeps uppermost the fact 

 that moisture can be his greatest enemy 

 and he designs accordingly. With the 

 proper safeguards, he knows that wood 

 construction can be entirely satisfac- 

 tory, safe, and economical, whether 

 prefabricated or conventional. 



RONALD F. LUXFORD has degrees in 

 civil engineering from the University 

 of Minnesota and the University of 

 Wisconsin. He has been with the For- 

 est Products Laboratory since 1918; 

 since 1935 he has headed the work on 

 housing research. 



F. A. STRENGE, a native of Chicago, 

 was reared on a dairy farm in Wis- 

 consin and was graduated from the 

 University of Wisconsin. After 7 years 

 of newspaper work, he joined the staff 

 of the Forest Products Laboratory in 

 1941 as a technical writer. Since then 

 he has written and edited various Lab- 

 oratory publications, including a 

 Manual on Wood Construction for 

 Prefabricated Houses and a series of 

 technical reports on housing research. 



THE GLUING OF WOOD 



DON BROUSE 



Gluing, when properly done, is the 

 strongest known means of fastening 

 pieces of wood together. Joints made 

 with glue are stronger than those made 

 with nails, dowels, screws, clamps, or 

 straps, because glue spreads in a uni- 

 form film that firmly binds together 

 every part of the surfaces to be joined. 

 Since its discovery, this property of 

 glue has destined it to an intimate as- 



sociation with wood in the innumer- 

 able products of joinery, veneering, 

 and cabinetmaking, for which it pro- 

 vides joints that can resist high stress 

 and violent shocks and that permit the 

 combining of wood into economical 

 thicknesses and into useful and ornate 

 shapes otherwise impossible. 



Although the bond of all glues, ex- 

 cept the synthetic resins, can be de- 



