For owners of warehouses, retail and office buildings
Commercial Roof Replacement Cost: 2026 Prices and Repair, Overclad or Replace
Sviatoslav JerdetchiiCEO & Founder of Craftex. Updated , 7 min read
The short answer
A full commercial flat roof replacement typically costs about £90 to £180 or more per m² in 2026 before VAT. Insulation to current Building Regulations, deck repairs, access and asbestos come on top.
- The system you choose sets the base rate, from about £80 per m² for felt to £150 for GRP.
- Insulation and deck repairs can add roughly £45 to £90 per m² between them.
- Overcladding or a targeted repair can beat a full replacement.
A full commercial flat roof replacement costs about £90 to £180 or more per m² in 2026, before VAT. Insulation, deck repairs, access and asbestos are extra.
This guide is for owners and asset managers of warehouses, industrial units, retail buildings and offices. Their roof leaks or is near the end of its life. It gives the rates by system, what moves the price and when to repair, overclad or replace.
Our commercial roofing contractors survey and cost roofs on buildings that stay in use. Roof leaking? Get a free roof condition survey and cost plan.
Commercial roof replacement cost per m² in 2026
The rate depends mostly on the roof system. Roofers who answer on MyJobQuote's trade Q&A in 2026 give a range for each one. Prices are per m² of roof, not floor, and exclude VAT.
| Roof system | £ per m² | What the figure covers |
|---|---|---|
| Three-layer torch-on felt | £80 to £120 | Strip and replace on a sound deck |
| EPDM rubber | £90 to £130 | Strip and replace on a sound deck |
| Single-ply PVC or TPO | £100 to £140 | Strip and replace on a sound deck |
| GRP fibreglass | £100 to £150 | Strip and replace on a sound deck |
| Any system, full strip and replacement | £90 to £180 or more | Higher-spec systems and deck repairs cost more |
Scale matters. A 2,000 m² roof at £90 to £180 per m² comes to £180,000 to £360,000 before VAT, extras and fees. One roofer's 2026 answer gives £16,000 to £24,000 for a straightforward 200 m² felt roof.
Our roof calculator uses £85 per m² for an overlay, £105 to strip and re-roof, and £170 to strip, insulate and fit a metal roof. Insulation upgrades add £20 per m².
What adds to the price
The base rate covers the covering on a sound deck. Most of the surprises sit in the items below, which is why a survey should price them before you sign.
| Item | Effect on the price |
|---|---|
| Insulation to current standards | Roughly £20 to £40 per m² on top |
| Timber deck replacement | Around £25 to £50 per m² on top |
| Scaffold and edge protection | Priced from the survey: roof height, perimeter and access decide it |
| Rooflights | Priced from the survey: fragile rooflights need protection and often replacing |
| Asbestos | Survey first, then a method: see the asbestos section |
| Out-of-hours or phased work | Priced from the survey: a live operation limits when and where we can work |
| Waste removal | Priced from the survey: strip-out of old layers is weighed and tipped |
Roof work is where construction people get hurt. HSE reports that almost one in five construction deaths involve roof work, mostly falls from edges and through fragile roofs and rooflights. Regulation 9 of the Work at Height Regulations 2005 requires platforms, coverings or guard rails where anyone must work on or near a fragile surface.
So edge protection and rooflight cover are not options. They are a cost the survey must show.
If the facade is failing as well, read our guide to curtain walling. It covers the walls the way this one covers the roof.
Our commercial roofing contractors price access, rooflights and waste as lines, so you can see what each one adds.
Repair, overclad or replace
Full replacement is not always the answer. There are four routes, and each fixes a different failure.
- Patch repair. Fix the leak at its source: a failed seam, flashing or outlet. It is the cheapest route and suits a roof that is sound apart from a few points.
- Coating and edge treatment. Clean, treat and recoat a roof that is ageing but sound. On a profiled steel roof, this includes cut edge corrosion at the sheet edges.
- Overclad. Fit a new covering over the old one. It avoids stripping and waste, but the structure must carry the extra layer.
- Strip and replace. Remove the covering and renew it. It resets the roof's life, and it triggers Part L insulation if it covers more than half the roof.
What does the survey need to show to choose between them? The checklist at the end lists it. In short: the condition of the deck and insulation, the state of the sheets and fixings, and what the structure can carry.
Cut edge corrosion
Cut edge corrosion is rust that starts where the factory coating on a steel sheet has been cut. Bare metal at the edge meets the weather. As the metal expands and contracts, the coating can lift and the rust spreads.
Treatment works while the sheet is still sound. Once the rust has gone through, the sheet has to be replaced.
When the lease decides it
If you are a tenant with a repairing covenant, repair may be enough. In Riverside Property Investments v Blackhawk Automotive in 2004, the court held that repair is enough where it is reasonably and sensibly possible. Our guide to dilapidations explains how roof claims arise at lease end.
Asbestos cement roofs
Many older industrial roofs are asbestos cement sheets. They need a different plan from the first day.
The Control of Asbestos Regulations 2012 give the dutyholder for non-domestic premises a duty to manage asbestos. That is the owner, or whoever is responsible for maintenance or repair. They must assess whether asbestos is present and consider its condition. HSE's guidance is to find it, record it and plan for it before work starts.
HSE says removing asbestos cement is non-licensed work if the sheets are carefully handled and removed without breaking up. It becomes notifiable if the sheeting will be substantially broken up, for example by dropping it. An asbestos cement roof is always fragile and cannot bear weight.
Overcladding can avoid removal. HSE asks whether the sheets can be overlaid with non-asbestos material, fixed to the existing purlins, without drilling through them. HSE's task sheet is for small-scale jobs. A large roof needs a full risk assessment and plan of work.
Great experience from start to finish. Communication was clear, the workmanship was excellent, and the whole project was managed professionally.
Part L, MEES and solar: when the roof must do more
A new roof is the cheapest moment to fix its energy performance. Three things can raise the specification.
| Driver | What it asks for | Where it stands |
|---|---|---|
| Part L, Approved Document L Volume 2 | Whole flat roof to 0.18 W/m²K if over 50% is renovated | Law now, 2021 edition |
| MEES | EPC E minimum, EPC B from 2031 proposed | E in force, B not law |
| Solar | A roof that outlasts the panels | Your decision |
Part L. Approved Document L treats replacing the waterproof membrane on a flat roof as renovation. If you renovate more than 50% of the roof surface, the whole roof should reach a U-value of 0.18 W/m²K. A lesser standard is acceptable only where that is not feasible or fails a 15-year payback.
The 2021 edition applies now. The 2026 edition takes effect on 24 March 2027 and keeps 0.18 for a flat roof.
MEES. EPC E is the legal minimum for most commercial lets today. EPC B from 2031 is proposed, not law. Read our guide to the MEES rules for commercial property before you set the insulation level.
Solar. An installer will want to know the roof will outlast the panels. Replace the roof first, then fit the array.
How to get a firm price for a commercial roof
A firm price comes from a survey, not from a rate per m². The survey should record what the roof is made of and what is under it.
A large job on a trading building also needs a plan. It runs in this order.
- Survey and test. Open sections, check the deck and log the sheets.
- Section the roof. Split it into bays, so only a small area is open at any time.
- Weather each bay. Make each section watertight before the day ends.
- Protect the operation. Keep loading bays, escape routes and fragile rooflights safe.
CDM and live buildings
Check CDM too. Under regulation 6 a project is notifiable if it lasts over 30 working days with over 20 workers at once. So is one that exceeds 500 person days. Our guide to CDM client duties explains what you must do.
We have built inside live buildings. At Banbury we delivered 148 m² in four weeks inside a live warehouse, with no stop to day-to-day operations. That was not a roofing job. It shows how we phase work around a trading business.
Use this list before you sign. Send us the address and photos, and get a free roof condition survey and cost plan. Already have a quote? Send it to us. We'll beat it.
- Core samples or an opened section showing each layer, the insulation and the deck
- Moisture survey of the insulation, so wet areas are priced as replacement and dry areas as repair
- Sheet and fixing condition, with every cut edge corrosion point logged
- Structure check: can it carry an overcladding layer or new insulation?
- Asbestos survey and a method statement, if the roof is cement sheet
- Rooflight count and condition, with fragile roof protection priced
- Repair, overclad and replace priced side by side
- Part L position agreed with building control: 0.18 W/m²K if over 50% is renewed
- Phasing, working hours and loading bay access agreed with the tenants
- CDM notification checked, and every extra named and priced
