Fasteners for structural timber: nails, staples, screws, dowels and bolts

Fasteners for structural timber: nails, staples, screws, dowels and bolts

Date Published

21 August 2022

Document Type




Timber designers usually consider connection design to be the most difficult area in timber Design > Engineer;ing. The traditional mechanical fasteners for structural timber are divided into two groups depending on how they transfer the forces between the connected members – ‘dowel-type fasteners’ and ‘metal connectors’.

This Wood Information Sheet (WIS) describes the dowel-type fasteners: nails, staples, screws, dowels and bolts. These fasteners can be CE marked in accordance with BS EN 14592. With these fasteners, the magnitude of load transfer between the connected members depends on the bending behaviour of the fastener as well as the bearing stresses developed in the timber along the shank of the fastener. Friction within the interface between the two connected members and axial pullout resistances could also contribute to the shear (lateral) capacity depending on the fastener type.

This sheet also details the applications of each fastening type including which types can be used to fasten timber to steel.

Key Information

Two types of mechanical fasteners are used in structural timber design – dowel-types and metal connectos.

Dowel-type fasteners are nails, staples, screws, dowels and bolts.

Proper fastener designs require the connection detailing to be appropriate as well as getting the capacity calculations correct.

Case studies

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