The National Structural Timber Specification (NSTS) refers to the use of structural timber wherever UK building regulations apply. A similar specification is already in place for steel and concrete. It is specific to UK construction and was produced by the Timber Development UK, formed by the merger of TRADA and the Timber Trades Federation. Access the latest version here.
It provides guidance for those using the supplementary Project Specification for Structural Timber which is available only to trade body members. Designers can download a number of templates to guide their use of timber products for a specific project, within NSTS guidelines.
NSTS works in conjunction with Eurocode 5. While this design standard covers requirements for mechanical resistance, serviceability, durability and fire resistance, it does not refer to specific national building regulations, nor does it include properties such as thermal or sound insulation, which are covered by NSTS.
All Eurocodes are under review and there are plans to add an ‘Execution’ section. This would remove the need for the NSTS.
The guide below matches US trademarked products with the relevant NSTS clause number and tells you which UK/EU standard applies.
APA Structural Products | NSTS Material Clause No. | EU and UK Standards |
---|---|---|
Plywood | 5.2.5 | (BS) EN 13986 |
OSB | 5.2.4 | (BS) EN 13986 |
LVL | 5.2.3 | (BS) EN 14374 |
I-joists | 5.3.1 | Manufacturers’ own EU or UK Technical Assessment |
Glued laminated timber | 5.2.2 | (BS) EN 14080 |
Cross-laminated timber | 5.2.7 | Manufacturers’ EU or UK Technical Assessment |
Structural softwood lumber | 5.2.1 | (BS) EN 14081-1 |
Structural Insulated Panels (SIPS) | 5.4.2 | Manufacturers’ EU or UK Technical Assessment |
APPLICATIONS | General Description | Plywood Grade Rated (with span rating) | Non-Rated Plywood Grade | Bond Classification/Glue Line | Exterior veneer grades | Exposure 1 veneer grades | Span rating/support spacing and designated loading | ||
NON-STRUCTURAL | Where appearance of both sides is important for interior applications, with smooth surfaces suitable for painting | A-A (NON-RATED) | US panels are available in two classifications: Exterior - equivalent to (BS) EN 314 Bond Class 3 or Exposure 1 (always includes D veneer) - Bond Class 2 | Face A; Inner C; Back A | Face A;Inner D; Back A | Span rating not applicable |