What stud centres are used in timber frame construction?

Standard stud centres in UK timber frame construction are 600mm (to match 1200mm wide sheathing boards) or 400mm for heavy loading. The 600mm centres ensure that board joints always fall on a stud. For load-bearing walls supporting roof or upper floor loads, 400mm centres or larger stud sections may be required by the structural engineer.

What size studs are used in timber frame walls?

UK timber frame walls typically use 89×38mm (3.5 inch) studs for standard storey-height walls. For deeper insulation cavities, 140×38mm studs are used. The stud depth determines the maximum insulation thickness within the wall. C16 or C24 structural graded softwood is required for load-bearing panels.

Why do timber frame panels need diagonal bracing?

Diagonal bracing (or racking resistance from sheathing) prevents the rectangular frame from racking (distorting into a parallelogram) under wind loads. OSB or plywood sheathing nailed at 150mm centres to all studs and rails provides racking resistance. Alternatively, let-in diagonal braces or metal strap bracing can be used.

How many sheathing sheets do I need?

Standard sheathing sheets (OSB3 or plywood) are 2440mm × 1220mm. Divide the panel length by 1.22m (sheet width) and round up. For a 6m panel: 6 ÷ 1.22 = 4.9, so 5 sheets. Sheets are fixed vertically with the 2440mm dimension matching the wall height. Use 9mm OSB3 minimum, 11mm for enhanced racking.

Do I need a DPC under the sole plate?

Yes, a DPC (damp-proof course) strip must be placed under the sole plate wherever it sits on masonry, concrete, or any material that could transfer moisture. Use a polyethylene DPC or bituminous felt at least 100mm wider than the sole plate. The sole plate should also be pressure-treated to UC3 or UC4 specification.

TradeCalculator.co.uk

Timber Frame Panel Calculator

Calculate studs, rails, noggings, bracing and sheathing sheets for timber frame wall panels at 600mm centres.

Panel Length

Total length of wall panel

Panel Height

Storey height (typically 2.4m)

Stud Size89×38mm standard, 140×38mm for deep insulation

Stud Centres

600mm standard for sheathing boards

Sheathing TypeOSB3 or plywood for racking resistance

Include diagonal bracing

Let-in diagonal brace for racking

Include sole plate with DPC

Treated sole plate on DPC

Price Per Stud (optional)

Price Per Sheathing Sheet (optional)

How We Calculate This

This calculator determines the studs, rails, noggings, bracing and sheathing for a timber frame wall panel. It uses standard 600mm centres and accounts for head/sole rails and horizontal noggings.

The formula

Studs = (Panel length ÷ Centres) + 1
Noggings = (Studs - 1) × Number of rows
Sheathing sheets = Panel length ÷ 1.22m (rounded up)
Bracing = √(Length² + Height²)