Date on Master's Thesis/Doctoral Dissertation
Ernst, Robert Craig
Committee Co-Chair (if applicable)
Williams, Gordon C.
Barnes, W. R.
This thesis presents the results of an investigation conducted to improve the weather resistance of plywood assemblies used in prefabricated housing manufacture. Specifically, this work involved water sealers for edge joints (called edge sealers), the prevention of surface transfer of water vapor through plywood (called vapor barriers), and fillers for structural defects in the wood (called core void fillers). Two edge sealers for plywood were developed that were considered successful in resisting water permeation. One was a quick drying paint formulated by the addition of 30 per cent leaded zinc oxide to 70 per cent Arco primer paint No. 156. However, a better but slower drying sealer was found in the use of two coats of 40 per cent leaded zinc oxide and 60 per cent glyceryl phthalate varnish. Two vapor barriers were developed that were successful in combatting moisture condensation in the stud space of exterior wall assemblies. One of these was an aluminum-gilsonite paint. The other was an aluminum foil bonded to the plywood. Either would reduce the moisture diffusion through wood in excess of 95 per cent. A method is presented that would make the use of aluminum foil economically feasible. A filler for core voids consisting of an asbestos extended resoreinol glue mixture was developed. The filler showed optimum resistance to weather conditions, heat and water bleeding, and had an excellent pot life.
Fear, James Van Dyck, "Water and water vapor barriers for structural plywood : II. core void fillers for structural plywood." (1947). Electronic Theses and Dissertations. Paper 1933.