Design of structural timber connections

TRADA image

Connections are an essential part of any structure, and in timber structures they are often the most critical part of a design. The timber section size is often determined by the strength of the section remaining after drilling holes for bolts or dowels, or by the spacing requirements for the fasteners, rather than the load-carrying capacity of the timber. Therefore the design of connections is an important section of any timber design standard.

When selecting and detailing connections for a particular application, designers must consider four criteria:

  • Load transfer
  • Fire resistance
  • Durability
  • Appearance


This Wood Information Sheet (WIS) focuses on the load transfer aspect and is intended mainly for engineers and architects. This WIS is an overview of the subject with signposts to more detailed sources that are listed at the end.



  • Connection types
  • Fastening methods
  • Design of laterally loaded connections
  • Design of axially loaded connections
  • Spacing of fasteners

This Wood Information Sheet was reviewed in February 2017 and minor corrections were made to the references section.

Suggested Reading

Wood-based panel products and timber in firenavigation-arrow

This Wood Information Sheet (WIS), intended for designers, specifiers and manufacturers, covers the behaviour of wood-based panel products such as plywood, particleboard and fibreboards, in addition to timber.

Smoke production is also considered.

This Wood Information Sheet applies to the United Kingdom and other jurisdictions where...

24/08/2020 |  Wood Information Sheet  

Flame-retardant treatments for timber productsnavigation-arrow

In many situations, timber and wood-based materials may be used in their natural, untreated state. However, flame-retardant (FR) treatments extend their use to situations that demand enhanced 'reaction to fire' properties.

This Wood Information Sheet (WIS) covers treatments that may be applied to wood and wood-based products both...

19/08/2019 |  Wood Information Sheet  

The National Structural Timber Specification for Building Constructionnavigation-arrow

The National Structural Timber Specification for Building Construction (NSTS) is an ambitious initiative by TRADA to support the rapidly increasing use of timber. It aims to be the definitive, comprehensive, stand-alone national specification for structural timber, complementing the existing national specifications that are widely used for steel and concrete buildings.


12/05/2017 |  National Structural Timber Spec