Evaluating wood-based composites for incipient fungal decay with the immunodiagnostic wood decay test.

Abstract

Early and accurate detection of the extent of fungal deterioration during forensic inspection of the building envelope would eliminate excessive or unnecessary replacement of wood-based building materials. Areas of water infiltration in wood-framed building envelopes in the Pacific Northwest were evaluated visually and sampled for moisture content. Wood samples were cultured in the laboratory and tested for the presence of decay fungi by the immunodiagnostic wood decay (IWD) test. In oriented strandboard sheathing, a correlation was seen between low moisture content, arrested fungal growth, advanced visual deterioration, and negative IWD results in a building envelope in which advanced fungal decay was discovered 3 years prior to the evaluation. Evaluation of exterior siding showed a correlation of high moisture content and of swelling and softening of the product with positive IWD results. We conclude that the IWD test should be used to indicate the presence of decay fungi in areas where high moisture content indicates a potential for biodeterioration, since moisture is a precursor for fungal growth.

Citation

Clausen, C.A.; Haughton, L.; Murphy, C. 2003. Evaluating wood-based composites for incipient fungal decay with the immunodiagnostic wood decay test. Gen. Tech. Rep. FPL-142. Madison, WI : U.S. Dept. of Agriculture, Forest Service, Forest Products Laboratory, 2003. 7 pages.