Skip to page content
USDA Forest Service

Research & Development Treesearch

Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help - We Participate  Government Made Easy

Global Forest Information Service

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

(202) 205-8333

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

Publication Information

View PDF (115 KB bytes)

Title: Improved grading system for structural logs for log homes

Author: Green, D.W.; Gorman, T.M.; Evans, J.W.; Murphy, J.F.;

Date: 2004

Source: Forest products journal. Vol. 54, no. 9 (2004): Pages 52-62

Publication Series: Miscellaneous Publication

Description: Current grading standards for logs used in log home construction use visual criteria to sort logs into either “wall logs” or structural logs (round and sawn round timbers). The conservative nature of this grading system, and the grouping of stronger and weaker species for marketing purposes, probably results in the specification of logs with larger diameter than would be required if a more precise grading method were available. This study evaluated the relationships between log strength and stiffness as a basis for a mechanical grading system. A sample of 120 logs, 4.9-m (16-ft.) long, was obtained from a mixture of fire-killed subalpine fir and lodgepole pine trees. The logs were tested in bending and in compression parallel to grain. Flexural stiffness as determined by transverse vibration was found to be the best single predictor of static strength and modulus of elasticity (MOE). The proposed mechanical grading system uses a combination of MOE and visual characteristics to predict mechanical properties. The proposed system is predicted to yield a higher strength for a givenMOEvalue than does the current visual system.

Keywords: Log grading, grading systems, structural logs, log homes

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.



Green, D.W.; Gorman, T.M.; Evans, J.W.; Murphy, J.F. 2004. Improved grading system for structural logs for log homes. Forest products journal. Vol. 54, no. 9 (2004): Pages 52-62


 [ 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.