Asbestos Barn Roofs and Solar: the Re-Roof-Plus-PV Route

The roof you have versus the roof solar needs

Walk around almost any British farm built before the year 2000 and you will find the same roof again and again: grey, corrugated, cement-based sheeting on the cattle court, the grain store, the implement shed. It is asbestos cement — a material that did its job for decades but cannot carry a solar array, and that you cannot simply screw panels into. For a great many barn owners, this is the real reason the roof is still bare while the energy bills climb. The good news is that the obstacle and the opportunity are the same thing: the re-roof you have been putting off and the solar install you want can be a single, part-self-funding project.

This guide explains why asbestos rules out direct PV, who is legally allowed to remove it, how the strip-and-reclad-plus-solar route works in practice, and why the numbers stack up better than doing either job alone.

Why you can’t put panels on an asbestos roof

Asbestos-cement sheeting fails as a solar substrate on two counts.

First, safety and the law. Drilling, cutting or even walking on asbestos cement releases fibres, and the material is regulated under the Control of Asbestos Regulations 2012 (CAR 2012). You cannot lawfully start fixing solar mounting into it, and disturbing it during an install would be both dangerous and a breach of those regulations. The HSE’s asbestos guidance sets out the duties that apply.

Second, structure and condition. Even setting the fibres aside, decades-old cement sheeting is brittle. It is not engineered to carry the added dead load of a PV array plus wind uplift, and many older sheets are already weathered, cracked or fragile underfoot. Loading panels onto them would be unsafe regardless of the asbestos question.

So the panels cannot go on the roof you have. They go on a new roof — and that new roof is where the project really begins.

Only licensed contractors may remove it

Removing an asbestos-cement barn roof is licensed work under CAR 2012. It must be carried out by a contractor holding the appropriate HSE licence, working to a written plan of work, with proper containment, controlled removal, air monitoring where required, and consigned disposal of the waste to a licensed facility with the correct documentation.

This is not a corner to cut. The point matters for the project plan because the asbestos strip is a specialist, scheduled, evidenced piece of work that sits at the very front of the programme — before any new cladding, before any panels. When we run a barn re-roof-plus-PV scheme, the licensed removal is built in from day one, with the disposal paperwork retained as part of the handover.

The strip-and-reclad-plus-PV route, step by step

The combined approach turns three separate problems — an ageing roof, an asbestos liability, and a bare south-facing canvas — into one sequenced project:

1. Survey and design. Confirm the roof is asbestos cement, assess the frame and purlins, and design the new roof and the array together so the cladding, fixings and panel layout all suit each other from the outset.
2. Licensed asbestos removal. A licensed contractor strips the old sheeting under controlled conditions and disposes of it correctly.
3. Structural check and any strengthening. With the roof open, the frame is confirmed fit to carry the new cladding plus the modest PV dead load (around 10–15 kg/m²). Older or modified frames occasionally need minor strengthening, which is far cheaper to do now than later.
4. Reclad in modern profiled steel. A new profiled-steel roof goes on — better insulated, watertight, and engineered as a clean, known substrate for solar.
5. Install the array on the new roof. Panels are fixed into the new cladding to a design that was planned before the first sheet went up, not retrofitted around it.

Because the steel roof is a brand-new, structurally-cleared surface, the PV install on top is fast and straightforward. This is the standard pattern for the modern agricultural sheds covered on our steel-frame portal barns page — the difference here is simply that you are creating that ideal steel roof rather than starting with one.

Why the combined project pays

The financial case is what makes this more than a grudge purchase. An asbestos barn roof is a liability you will have to deal with eventually anyway — it degrades, it is a known hazard, and it can complicate a sale or a lease. The re-roof is largely an unavoidable future cost.

Layer solar on top and the picture changes. The array generates electricity you would otherwise buy and, on a working barn with real on-site load, it can pay for itself in a handful of years. For an owner trading through a business, 100% Annual Investment Allowance can write the qualifying plant off against tax in year one, and the Smart Export Guarantee pays for the surplus you export. In effect, the income and tax relief from the solar half of the project offset a meaningful slice of the re-roof you needed regardless — so you end up with a new roof and a generating asset for far less than the two jobs would cost done separately and years apart.

The exact split depends on your roof size, your load and your tax position, which is why we model it from your meter data rather than quoting a rule of thumb. You can see how the underlying solar economics break down by system size on our cost guide.

A common scenario

Consider a typical farm with a large cattle court under ageing asbestos cement and a smaller adjacent shed in the same condition. Rather than re-roof reactively when a storm finally takes a sheet off, the owner brings both roofs into one programme: licensed strip, structural sign-off, new insulated steel cladding, and a single array spanning the main clear span. The solar income and first-year tax relief recover a substantial portion of the cladding cost, the asbestos liability is gone for good, and the farm comes out with a watertight 30-year roof working as a power station. This is an illustrative example, but it is the shape almost every asbestos-plus-solar barn project takes.

The same logic applies right across the rural estate — our sister site solarpanelsforfarmbuildings.co.uk covers the wider mix of agricultural buildings where pre-2000 asbestos roofs are just as common.

We deliver both halves as one project

Re-roofing and solar are usually sold by different trades, on different timelines, with neither party owning the join. We run them as a single scheme: the licensed asbestos removal, the structural check, the new profiled-steel roof, and the PV array all designed and sequenced together, with the disposal evidence and warranties handed over at the end. One project, one point of contact, one new roof earning its keep.

Got an asbestos barn roof you have been putting off? Request a free assessment and we will survey the roof, confirm the strip-and-reclad-plus-solar numbers from your own figures, and show you how the solar half offsets the re-roof.