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UK Timber Connectors & Straps Guide
Framing anchors, truss clips, joist straps and restraint straps with sizes, fixing requirements and BS EN 14545 references.
Framing Anchors
L-shaped connectors for joining joists, rafters and studs to plates and beams. Comply with BS EN 14545.
| Type | Dimensions (mm) | Fixing | Typical Use |
|---|---|---|---|
| Standard framing anchor | 38 x 100 x 59 | 4 x 30 mm nails per leg | Joist to wall plate, rafter to plate |
| Heavy-duty framing anchor | 47 x 133 x 75 | 6 x 30 mm nails per leg | Heavy rafters, trimmer connections |
| Skewable framing anchor | 38 x 128 x 63 | 5 x 30 mm nails per leg | Angled connections, hip rafters |
Truss Clips
Secure roof trusses to the wall plate, resisting uplift forces.
| Type | For Truss Width (mm) | Fixing | Uplift Resistance (kN) |
|---|---|---|---|
| Standard truss clip | 35–47 | 3 x 30 mm nails each side | ~2.0 |
| Heavy-duty truss clip | 35–75 | 4 x 30 mm nails each side | ~3.5 |
Restraint Straps
Required by Approved Document A to tie walls, floors and roofs together. Minimum specification: 30 x 5 mm galvanised mild steel.
| Strap Type | Length (mm) | Section (mm) | Application |
|---|---|---|---|
| Lateral restraint (straight) | 1000 | 30 x 5 | Joists parallel to wall, across 3 joists |
| Lateral restraint (bent) | 1100 | 30 x 5 | Joists perpendicular, turned down wall |
| Heavy-duty restraint | 1200–1500 | 30 x 5 | Gable walls, high-exposure sites |
Joist Straps & Noggin Straps
| Type | Typical Size | Use |
|---|---|---|
| Herringbone strutting | 38 x 38 mm timber or metal | Between joists to prevent twisting (spans over 2.5 m) |
| Solid blocking | Same depth as joist | Between joists at supports and mid-span |
| Metal herringbone strut | Adjustable 150–250 mm depth | Quick-fit alternative to timber strutting |
Related Calculators
See the Joist Hanger Sizes guide for hanger specifications, or the Timber Span Calculator for sizing joists.
Frequently Asked Questions
Related Calculators
UK Joist Hanger Sizes
Standard joist hanger sizes for 47 mm and 75 mm timber with masonry and timber-to-timber types and safe working loads.
UK Timber Sizes
Standard UK timber sizes in CLS and regularised with metric and imperial equivalents.
UK Screw and Fixing Sizes
UK screw gauge sizes, lengths and pilot hole diameters for wood, masonry and metal fixings.
Fixings Guide by Wall Type
Fixing types and pull-out loads by wall material: brick, block, plasterboard, timber and concrete.
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Last updated: April 2026
Verified against UK standards · estimates only, confirm with your supplier.