Timber-frame construction has hovered around 9-10% of UK new-build delivery for a decade, with annual growth tracking single digits. The Future Homes Standard may be the catalyst that finally moves it materially higher.
Why timber suits FHS
Two FHS requirements are inherently easier in timber frame than in masonry. (1) U-value 0.15 on walls: a 250 mm I-joist studwork build-up with full-fill mineral wool hits the figure with conventional detailing. Equivalent masonry requires a 150 mm full-fill cavity which pushes the wall thickness toward 350 mm overall — eating valuable plot footprint. (2) Air permeability 3: timber-frame factory-built panels typically achieve 2-3 m³/(h·m²) without deliberate sealing; site-built masonry typically tests at 5-6.
Solar integration advantages
In-roof solar installs cleanly on timber-frame roof trusses — the lighter cassette weight (typical in-roof system weighs 12-15 kg/m² panel area) is well within the structural capacity of any I-joist truss design. Roof trusses can be factory pre-fit with in-roof solar tray openings, allowing panel installation to happen at the panel fabricator rather than on site.
Capacity constraints
UK timber-frame supply chain capacity sits at ~30,000 dwellings/year against an FHS-era demand projection of 60,000+ /year by 2028. Major suppliers (Stewart Milne pre-administration, Donaldson, Innovaré, Robertson Timber Engineering) are investing in factory capacity but the lead times for new panelised frame orders extend into 2027 for some volume housebuilders. Top-tier developers are securing 2026-28 capacity through bilateral contracts rather than spot procurement.
Cost comparison
Timber-frame whole-build cost is approximately on par with traditional masonry at 2026 prices — within ±3% on a typical 3-bed semi. Reaching FHS spec can cost less in timber frame, because timber-frame walls often already approach the fabric performance the standard assumes.
Implications for the 2026-28 transitional period
Developers with existing masonry supply chains face a higher per-plot incremental FHS cost than developers with timber-frame programmes. We expect timber-frame share of new-build delivery to lift from ~10% in 2024 to ~15-18% by 2028 as the supply-side capacity catches up with the regulatory pull. Marginal cost economics now favour timber, particularly on smaller plot sites where the wall-thickness savings translate directly to plot revenue.
MMC weight limits: the practical constraint
Timber-frame is one MMC route; for the full weight-band picture across volumetric and panelised systems — panel kg/m², roof loading and factory pre-fit — see our guide to lightweight solar for modular buildings.
