Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help
 

Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (159 KB bytes)

Title: The role of water repellents and chemicals in controlling mildew on wood exposed outdoors

Author: Feist, W. C.;

Date: 1984

Source: (Research note FPL ; 0247):15 p. : ill. ; 28 cm.

Publication Series: Research Note (RN)

Description: The natural look of wood siding, and the retention of that look, has become increasingly popular over the past several years. Many new commercial formulations are being offered for use as clear natural wood finishes. A successful finish will retain color, control mold and mildew, and minimize weathering. Some of these formulations contain a chemical as a mildewcide (fungicide, preservative) and/or a water repellent, and some do not. To evaluate several chemicals (alone or in combination with water repellents) as components of natural finish formulations, we dip-treated ponderosa pine sapwood specimens in various formulations and exposed them on test fences in Mississippi, Wisconsin and Washington. Several chemicals were very effective at controlling mildew and maintaining the natural appearance of the exposed wood. Aqueous formulations of chromium salts were the most effective for up to 22 months exposure outdoors. Many chemical formulations in mineral spirits (including water repellents and wood sealers) were effective for 5 to 9 months of exposure, but their effectiveness was reduced with longer exposure. Of all the chemicals evaluated in mineral spirits formulations, only pentachlorophenol and copper naphthenate were found to be effective mildewcides after exposures of greater than 9 months. Their mildewcidal effectiveness was improved with the addition of a simple water repellent (paraffin wax), especially with exposures greater than 9 months. Mildew growth was markedly worse in the warm, humid climate of Mississippi than in Washington or Wisconsin. This means that natural wood finishes for climates similar to Mississippi must contain high concentrations of effective mildewcides for good performance. This paper should be useful to homeowners, architects, builders, and wood finish formulators.

Keywords: Water repellents, Finishes, Weathering, Fungicides, Preservatives, Pentachlorophenol, Copper naphthenate, Mildews, Mississippi, Wisconsin, Washington, Wood siding, Mildewcide, Natural finish, Test fences, Chromium salts

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

XML: View XML

Citation:


Feist, W. C. 1984. The role of water repellents and chemicals in controlling mildew on wood exposed outdoors. (Research note FPL ; 0247):15 p. : ill. ; 28 cm.

 


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.