BIPV — Building Integrated Photovoltaics — was the premium option only architects could justify two years ago. In 2026 it is mainstream on architect-led custom builds and increasingly viable on volume Conservation Area infill plots. The cost story is the reason.
Cost trajectory 2024 to 2026
In 2024 a typical 5 kWp BIPV installation cost £18,000–£25,000 against £6,500–£8,500 for equivalent in-roof. Today the BIPV range is £11,500–£16,000 — a 38% reduction. The closing of the gap reflects production scale, particularly at GB-Sol, Marley SolarTile and the China-supplied solar slate market.
The four leading UK BIPV products
Marley SolarTile — UK-manufactured, integrates with Marley clay and concrete tile ranges. ~£2,400/kWp installed. Best for new-build estates wanting a tile-matched aesthetic.
GB-Sol PV Slate — Welsh-manufactured slate-matching BIPV. ~£2,750/kWp installed. The default for Cotswold, Lake District and Welsh slate Conservation Areas.
Viridian Clearline Fusion — Manufacturer since 2015, panel-form not tile. ~£1,950/kWp installed (lower because it is panel, not tile).
Tesla Solar Roof — Now selling in UK at scale, ~£3,200/kWp installed. Mostly premium custom builds.
When BIPV makes economic sense
On a self-build where the alternative is £6,000 of conventional slate roofing, BIPV slate at £14,000 is only £8,000 more — and generates 5 kWp of electricity over 25 years. On a Conservation Area plot where panel PV would be refused planning permission, BIPV is the only compliant option. On a volume development with no aesthetic constraints, in-roof panel solar remains the economic choice.
Outlook to 2028
We expect a further 15–20% cost reduction by end-2027 as FHS demand pulls UK BIPV manufacturing to higher volumes. Beyond 2028, BIPV and in-roof panel costs may converge for volume work in heritage areas.
