Canada Wood Today | The Canada Wood Group

HOWTEC New Span Table for P&B

Hidehiko Fumoto

By Hidehiko Fumoto

Deputy Director and Manager Technical Services, Canada Wood Japan

May 2, 2012

Structural calculations are required for post and beam wooden houses when the homeowner wants his or her home designed to the performance labelling system standards even in cases for one or two storey homes.  For this practice, designers have been using span tables when they wish to label a house with Rank 2 or higher.  The Japan Housing and Wood Technology Centre (HOWTEC) published the first version of the span table in November 2000.  HOWTEC recently revised the span table to 2012 version and conducted seminars to explain it.  The main revisions were made to review the dead loads and to reflect structural calculation manual (known as Grey Book) also published by HOWTEC.  This span table is essential not only for the performance labelling but also for the case where one wants a longevity housing approval.  In such a case, structural performance of minimum of Rank 2 is required for the longevity approval.