Asbestos cement barn roofs and solar: the 2026 UK guide

Asbestos cement was the dominant agricultural roof cladding from the 1950s through to the late 1980s — robust, cheap, fire-resistant, and (it turned out) a long-term liability that today blocks rooftop solar PV on a significant share of the UK’s farm-building stock. The good news in 2026: the combined re-roof and PV business case is well-established, trained asbestos contractors operate routinely in every UK region, and the maths usually works.

The regulatory position

The Control of Asbestos Regulations 2012 (CAR 2012) prohibits any drilling, fixing, or load-imposing work on asbestos cement cladding. There is no derogation for solar PV. Any rooftop PV install on a building with asbestos cement cladding must follow one of two paths: (1) strip-and-reclad, removing the asbestos under licensed conditions and installing new cladding before any PV work; or (2) total roof replacement as part of the PV project. Either way, only trained asbestos contractors can carry out the removal work, and an Asbestos Removal Notification (typically 14 days) must be lodged with HSE before work starts.

What it costs

In 2026, asbestos cement removal by trained operatives costs typically £30–£50 per square metre depending on the building size, access complexity, and disposal route. Replacement profiled steel cladding adds £45–£80 per square metre installed. So a 2,000 sqm asbestos-clad barn roof typically costs £75,000–£130,000 to strip and re-clad before any PV work. PV install on top adds the standard £750–£1,000 per kW.

The combined business case: a 200 kW PV install on the new roof generates around 180,000 kWh per year, saving £40,000+ annually for a farm with strong daytime self-consumption. Over the 25-year system life, this typically pays for the entire re-roof and PV cost with a 6–9 year overall payback. The farm gets a modern, watertight, structurally improved roof AND a renewable energy asset for a single capital outlay.

When NOT to combine

There are situations where re-roof and PV should be sequenced rather than combined: (1) the building’s structural frame is also compromised — frame replacement is a different scope of work entirely; (2) the building’s use is changing and the future use doesn’t suit PV (residential conversion, demolition); (3) the building is small enough that the re-roof economics don’t stack alongside PV; (4) the operator has very limited capital and is making the re-roof a priority but cannot fund PV alongside.

Picking an trained asbestos contractors

HSE publishes the current asbestos licence holders register. Look for: licence currency (not expired or revoked), recent track record on agricultural buildings specifically (not just commercial/industrial), insurance cover at the appropriate level, and willingness to coordinate with the PV installer on shared scaffolding and access. The best combined projects use a single principal contractor coordinating the asbestos team, the cladding installer, and the PV team under one programme.

Planning and grants

Permitted development under Class A Part 14 GPDO 2015 typically covers the re-cladding (replacement of like for like, no change of use) AND the rooftop PV. No planning permission is normally required unless the building is listed or in a designated landscape area. The 100% Annual Investment Allowance applies to the PV portion of the capex (plant and machinery) but typically not the re-roof (building fabric) — talk to your accountant about how to apportion the bill of materials and labour for tax purposes. SFI has no asbestos-related or solar action.

Our typical project

Combined re-roof and PV projects are now routine across the UK. Typical project: 1,500–3,000 sqm of asbestos cement, removed in 4–8 weeks, re-clad in profiled Plastisol-coated steel, with 150–400 kW of PV installed in the following 2–4 weeks. Total project duration from contract to commissioning: 4–7 months. Single mobilisation saves £20,000–£50,000 versus sequenced delivery on multi-building projects.

If you’re planning a roof replacement on an asbestos-clad farm building, factor PV into the decision from day one — the combined business case is almost always stronger than re-roof alone.