NLT(Nail-laminated Timber) Tests to Open Doors in Floor Beam Applications

Shawn Lawlor

By: Shawn Lawlor

Managing Director, Canada Wood Japan/COFI Japan

As part of our Canada Wood Market Access initiative this year, we conducted a series of full-scale 6-metre span bending tests for Nail-Laminated Timber (NLT) floor beams.  In this project, we have been striving to produce performance data to enable the replacement of competing beam products with NLT floor beams.

These beam bending tests were designed to evaluate the overall bending performance and the behaviour of the NLT beams under the vertical load.  The tests were conducted at the Nagano Prefectural Forest Research Laboratory from December 18th to 25th.

During the course of the NLT panel test program, university researchers and Japanese 2×4 industry panel producers identified the possibility of utilizing NLT not only in panel form but in floor beam applications as a simple, practical and cost-effective alternative to engineered wood beams.  The purpose of this project was to conduct bending tests on NLT beams comprised of nailed together dimension lumber.  Tested beams were formed of Canadian lumber butted together vertically on edge and nailed.  The tests will verify butt joint performance and enable modelling of NLT beams of multiple width combinations: 4-ply, 5-ply, 6-ply, etc.

It is expected that the test evaluation body will issue a final voluntary evaluation report during fiscal 2021.  With this evaluation in hand builders will be able to apply for and receive building permit approvals for dimension-based NLT floor beams applications in platform frame or post & beam constructions.