Research conducted to measure the performance of PSL when exposed to fire demonstrates that it is appropriate for use in all applications for which solid sawn lumber and timbers are suited.
As a result of evaluations done in Canada by the Canadian Construction Materials Center (CCMC) and in the US by the Council of American Building Officials (CABO) PSL has been accepted for use in Heavy Timber construction when of appropriate cross section. Like timbers and glulam members, PSL of large cross section has proven to be resistant to fire because the low thermal conductivity of wood retards heat penetration, and slow charring rates allow these large members to maintain a high percentage of their original section.
The Fire Safety Design in Buildings book provides further information on building code requirements relating to fire safety and details the minimum size requirements for Heavy Timber construction.
General guidelines for PSL:
- Determine the load capacity required.
- Select size of PSL member which will meet the required load capacity.
- Ask the local distributor for technical literature and contact the manufacturer if engineering assistance is required.
- Determine if PSL members will be directly exposed to weathering or high temperature and high humidity for significant periods during the life of the structure. If so, consult with the manufacturer for information about preservative treatment.
- Check local availability for sizes and lengths.
- PSL is a patented product manufactured in both Canada and the US. For additional product information or technical information, contact Weyerhaeuser.