addition of chemicals the combustion 

 of wood can be materially retarded, the 

 danger of spread of fire in and by 

 wooden structures can be largely de- 

 creased. Laboratory research in this 

 field extends over a wide range of chem- 

 ical treatments and types of fire-resis- 

 "ive construction. Treated wood speci- 

 mens are tested in specially designed 

 combustion apparatus. Full-sized 



RE-11208-M4 



In fireproof ing investigations full-sized house 

 parts are subjected to test in a panel furnace. 



house parts are subjected to flame test 

 in a separate building equipped with a 

 panel furnace having 67 large gas 

 burners. Although highly effective fire- 

 proofing treatments are now available, 

 they are too expensive for general con- 

 struction purposes. The objective of 

 research is to reduce costs and to bring 

 the benefits of fire-retard ant wood 

 within reach of the average home 

 builder. 



Painting and 

 moisture-proofing 



The Laboratory is making definite 

 contributions toward more lasting and 

 satisfactory service of paints and other 

 coatings used on wood. The relative 

 efficiency of large numbers of moisture 

 retardants and varnishes has been deter- 

 mined. Exposure tests of painted 

 panels in many locations have demon- 

 strated the relative paint-holding power 

 of the principal commercial wood 

 species. Useful discoveries have been 

 made in methods of applying paint to 

 wood and the choice of priming mate- 

 rials. 



Examination of numerous failures in 

 the repainting of houses shows, how- 

 ever, that the life of a coating cannot be 

 wholly predicted from the immediate 

 conditions of application, but that the 

 service given depends on a proper or 

 improper combination of the new paint 

 with coats that have preceded it. 

 This fact points to the need of a 

 thoroughgoing classification of house 

 paints according to the long-time 

 maintenance programs of home owners. 

 The work of classification, recently 

 begun, involves a wide range of chemi- 

 cal research and service tests. The 

 findings already indicate that by a 

 proper distinction of paint types the 



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