Hem-Fir testing completed

'pnelrvrNaRy rESr onre analysis of I Hem-Fir lumber samples from western mills indicates no change to published Hem-Fir lumber design values is needed. The Hem-Fir lumber testing was conducted in 2014.

A Hem-Fir testing report by the cooperating agencies is being drafted for submission to the American Lumber Standard Committee board of review. It is anticipated the report will be submitted this month.

Hem-Fir is a species combination of western hemlock and five of the true firs: California red fir, grand fir, Noble fir, Pacific silver fir, and white fir. While species in this group are sometimes marketed separately in products graded for appearance, these species share similar design values making products graded for structural applications interchangeable. The lumber design values published for Hem-Fir are applicable to the White Fir species group of the five true firs.

The Hem-Fir species combination is one of the most important in the western region, second only to the Douglas Fir-Larch species group in terms of abundance, production volumes, strength and versatility in end use. The growth range of the species included in the group covers both the Inland and Coast lumber producing regions in the West.

Representative lumber test samples were taken from over 35 mills producing 2x4 dimension lumber in westem hemlock and the five true firs. The testing for the western lumber sample was conducted by Western Wood Products Association in cooperation with the Pacific Lumber Inspection Bureau, Redwood Inspection Service, Timber Products Inspection, and West Coast Lumber Inspection Bureau. These western agencies have been working together since 20ll on the testing program to monitor western lumber desien values.

Current published lumber design values are based on the in-grade lumber testing program. The testing was conducted in accordance the plan approved by the ALSC board of review. The plan calls for the destructive testing of lumber samples in bending of Hem-Fir No. 2 grade 2x4.

The preliminary data comparison to the Hem-Fir properties established in the original in-grade testing program indicates no change is required to the currently published design values. The monitoring program affirms current uses and building code recognition. The recognized span data for the species group will also remain the same. Had the data indicated a shift in properties, the test findings would have been reviewed by the cooperating agencies' memberships and appropriate actions taken. The final data analysis will be reviewed by the USDA Forest Products Laboratory for the approval of the ALSC board of review.

The testing of western species lumber is conducted periodically to monitor for changes required to the published lumber design values. The testing allows the lumber agencies for timely actions to be taken if needed to support western lumber products.

By Softwood Export Council