Quote a single figure for a commercial roof and it will mislead, because no two buildings are alike. A single-storey workshop with a low eaves and a clear yard is a different job from a two-storey office block squeezed against a neighbour in the town centre, even if the roof area is the same. The covering is only one line on the bill. Access, the state of the deck underneath, drainage, insulation and the need to keep the business running all add their own.
This guide takes published UK ranges for the covering, then walks through the other drivers one at a time so you can see why a quote moves. Every range here comes straight from a published national guide, and none is a figure we charge. Yours arrives after a survey, as a written quote. If you are weighing an overlay against a strip, our guide to overlaying a commercial roof covers that option, and the wider picture of our commercial work starts at commercial roofing.
What a published per m2 figure includes, and what it leaves out
National cost guides publish ranges because a range admits the spread. MyBuilder's flat roof guide, updated in August 2026, gives a typical replacement bracket and then a rate per square metre for each covering. Checkatrade's repair guide, updated in October 2026, does the same for repairs and states that its figures exclude VAT and exclude access. Those two small phrases matter. A rate that leaves out access has left out scaffold, edge protection and any hoisting, and on a tall building that can be a large item.
Both guides are written around houses, extensions and small outbuildings. A large industrial roof does not scale up from them in a straight line. A bigger area can lower the rate for each square metre, because labour and the fixed costs of getting on site are spread further. Awkward plant, parapets, upstands and rooflights push it the other way. Use a published rate to check that a quote is in the right country, not as a price for your building.
What belongs on a commercial quote
We write a commercial figure to cover access and edge protection, stripping and disposal, deck repairs, insulation, the new covering, flashings and details, drainage, rooflights where they are included, and making good. If one of those is missing from a quote you hold, ask whether it is included or whether it will arrive later as an extra.
Typical ranges by roofing system
Flat and low-pitch commercial roofs are covered with felt, single-ply membrane, liquid-applied coatings or profiled metal. For felt, rubber, fibreglass and PVC, national ranges exist. The table sets two sources side by side, and the difference between them is useful because they measure slightly different things.
| Covering | Replacement, MyBuilder flat roof guide (Aug 2026) | Repair, Checkatrade (Oct 2026, ex VAT, excludes access) |
|---|---|---|
| Bitumen felt | £70 to £100 per m2 | £100 to £140 per m2 |
| EPDM rubber | £90 to £130 per m2 | £120 to £170 per m2 |
| GRP fibreglass | £95 to £150 per m2 | £130 to £180 per m2 |
| PVC single-ply | £95 to £140 per m2 | Not listed |
| Lead | £150 to £200 or more per m2 | Not listed |
Repair rates sit above replacement rates for the same covering, which is normal: a small area carries the same set-up cost as a large one, so each square metre costs more. And the spread between the lowest and highest priced covering is narrower than many owners expect, so the choice between systems is seldom settled on the membrane price alone.
Lifespan is where the systems separate. GreenSpec puts EPDM at 20 to 30 years, while the Building Centre gives more than 25. Less describes a good felt job as lasting up to 20 years and a poor one failing inside 10. Treat those as ranges that move with exposure and workmanship. Our guides to commercial roof systems and single-ply membranes set the options against each other.
Area, height and access
Size is the obvious driver, but height and reach do as much to a budget. A ground-floor lean-to can be worked from a tower. A first-floor roof over a shop needs scaffold along the street frontage, with a protected walkway for passers-by. A unit set back behind a yard may need only edge protection around the perimeter. The gap between those three can run to a four-figure sum before any covering is laid.
Scaffold and edge protection
MyBuilder puts scaffold for a typical house re-roof at about £1,125, and Checkatrade gives £700 to £1,300. Those are domestic numbers, and a commercial building with a long elevation needs a longer run. Scaffold is priced by the length and height of the building, not by the area of the roof, so a long, narrow unit costs more to scaffold than a compact one with the same floor area.
Getting materials up and rubbish down
Rolls of membrane, boards of insulation and bundles of sheet all have to go up, and the old covering has to come down. On a low unit that is a yard and a skip. On a building tight to a lane, with a loading restriction or a neighbour's boundary, it may take a hoist, a lorry-mounted crane or restricted delivery times. Steep lanes and awkward access go into the written quote at survey, not discovered on the day.
Waste
MyBuilder's new-roof guide gives disposal for a house as anywhere between £100 and £1,000, a spread that tells you it depends on what is coming off. A stripped built-up felt roof with thick old insulation weighs and bulks far more than a single layer of membrane, and the quote allows for the waste.
Insulation, falls and the cost of bringing a roof up to standard
Part of the extra cost on a stripped commercial roof can sit underneath the covering. If the old roof is taken back to the deck, the insulation layer is rebuilt at the same time, and that is also when the building is looked at against current thermal rules. The Planning Portal explains that a roof renovation reaching beyond set limits can bring in a thermal upgrade, and the Part L approved documents carry the standards. Which volume applies to a shop, unit or office, and what it asks for, is a question for your building control body. We raise it at survey, before the strip.
Falls and drainage
No flat roof should be truly level. BS 6229 covers the design of falls, and IKO and Rockwool both explain that a roof should be designed for 1:40 so that the finished fall reaches at least 1:80 once building tolerances and sag have used up some of it. If the deck has settled and holds water, a sound fall may need tapered insulation, which costs more than flat boards but cures ponding rather than covering it over. Standing water sits behind many early failures, so that money is usually well placed.
Fixings and weight
Changing from a light covering to a heavier one, or the reverse, alters the load on the structure. The Planning Portal says a covering that increases roof weight by 15 per cent or more needs Building Regulations approval, and suggests speaking to a structural engineer or surveyor beforehand. On a steel-framed unit that is a check on purlin and rafter capacity; on a masonry building with timber joists it is joist size and condition. If a check is needed, it is included in the quote.
Old sheets, asbestos cement and hidden defects
Industrial and agricultural roofs from earlier decades sometimes carry asbestos cement sheeting. HSE guidance classes asbestos cement roof sheets that are lifted off carefully and kept in one piece as non-licensed work. When they are badly damaged, or would shatter on the way out, it becomes notifiable, which means notifying before work begins, health checks and record keeping. Where sheets are intact, we plan so they come off whole, following the guidance at hse.gov.uk.
On cost, MyBuilder's asbestos removal guide quotes £50 per m2 at the low end and puts a single garage roof between £350 and £1,295. Those are small domestic roofs. A commercial roof is priced after a survey that identifies the material first, because everything on the quote hangs on whether the sheets stay, are overclad or come off.
What turns up once the covering is off
Every strip shows something the survey could not. A deck wet for years, rafters rotted at the wall plate, purlins rusted on the surface, rooflight kerbs that have given way. Some of that is visible from a hatch or a drone and some is not. A sound quote is honest about what we can see and what we cannot, and says how an extra repair would be measured and priced, so it is agreed rather than argued about.
Ask every contractor how a hidden defect will be priced if it appears under the old covering. A clear answer on paper is worth more than a low headline figure.
Phasing, trading and the cost of working around a business
A roof over an empty building can be stripped in whatever order is quickest. A roof over a working unit cannot. If the business keeps trading, the work goes in sections: one bay is stripped, dried in and covered before the next is opened, with temporary protection between. That sequence is slower than a clean strip, so more days on site are paid for, and it takes more care with dust, noise and the routes people use to reach the door.
Why phasing is worth paying for
An opened roof is a waterproofing risk against the clock. Phasing limits the area exposed at once, so a change in the weather costs a few square metres of temporary sheeting rather than the whole roof. Where stock, machinery or records sit below, that protection is what makes the work acceptable.
Out-of-hours and weekend work
Some owners prefer noisy work done while the unit is shut. That is possible, but evening and weekend working carries a premium, and the quote makes that plain rather than folding it into labour. Short winter days also lengthen a programme, which is a reason to agree a start date at survey.
VAT
GOV.UK's VAT Notice 708 describes work to an existing building as normally standard-rated, so VAT is stated on the quote. If the building is let, who bears and who recovers it depends on the lease and your own VAT position, which is a matter for your accountant.
From a repair to a full replacement: reading the ladder
Commercial roof work sits on a ladder, with a patch at the bottom and a full strip and re-cover at the top. Where your roof belongs depends on what is wrong and how much of the roof is wrong.
Spot repairs
MyBuilder's roof repair guide prices minor repairs at £100 to £300, moderate ones at £500 to £1,000 and major ones at £2,500 and above, across all roof types. Those fit isolated faults: a split seam, a failed flashing, a punctured sheet. Repair makes sense while the covering around it is sound. When the same roof needs patching every season, repeated call-outs begin to approach the price of a proper job.
Refurbishment and overlay
Between a patch and a strip sit coatings, overlays and partial re-covering. They cost less than a full strip because the old layer stays, but they depend on that layer and the deck beneath being sound enough to carry the load. Our guide to the commercial roof overlay sets out when that holds.
Full replacement
A strip and re-cover costs the most today and is the only route that lets us inspect and renew everything underneath. It is the right answer when the deck is damaged, the insulation is saturated, or the roof has been overlaid once already.
Whichever rung you are on, the written quote we write once the roof is surveyed comes with photographs taken on your roof, and carries a 10-year workmanship guarantee in writing. To get started, send the address, the approximate area, the existing covering if you know it, and any photographs.