- Guide price
- £15,900–£26,150
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
London at a glance
- Largest towns
- Westminster, Camden, Islington, Haringey
- Postcode areas
- BR, CR, DA, E, EC, EN, HA, IG, KT, N
- Building control
- City of Westminster, London Borough of Camden, London Borough of Islington and 29 other councils
- Neighbouring areas
- Surrey · Hertfordshire · Buckinghamshire · Berkshire
- Guide price region
- London (+20% on West Midlands rates)
How much does a commercial flat roof cost in London?
Guide prices including VAT at London rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Commercial roof (100 m²), single-ply + insulation | £15,900–£26,150 |
| Condition survey and leak investigation | £180–£360 |
| Block of flats (150 m²), felt + insulation + scaffold | £18,650–£32,650 |
Which flat roofs are common in London?
Flat roofs in London sit on kitchen extensions and roof terraces behind period houses, shops with flat-roofed stores below flats above and mansard and dormer loft conversions. The Thames basin is one of the drier parts of Britain at roughly 730 mm of rain a year, but summer heat is the bigger test here: dark membranes on south-facing roofs swing a long way in temperature. Approximate 1991–2020 regional averages based on Met Office data.
Building regulations in England
Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. Renovated roofs over heated rooms are insulated to around 0.16 W/m²K where that's feasible, and new extension roofs are built to 0.15 W/m²K. In London the application goes to City of Westminster, London Borough of Camden, London Borough of Islington and 29 other councils. More on the rules.
How do you handle CDM, roof access and fragile surfaces?
Every job is planned under the Construction (Design and Management) Regulations 2015, or CDM (NI) 2016 in Northern Ireland, with a construction phase plan and a method statement for the roof.
As a commercial client you have duties under CDM too, including passing on information about the building, such as drawings, details of previous roof work and the asbestos register. Buildings put up before 2000 can contain asbestos, so we ask for the register or a refurbishment survey before pricing a strip-out. If asbestos is found, a licensed specialist surveys and removes it before we start.
Roofs and rooflights are treated as fragile until a competent person confirms otherwise. Edge protection goes up on every job, rooflights and fragile sheets are covered or fenced off, and we agree safe access before work starts: scaffold, a tower, a powered access platform or a fixed access point where one is suitable.
Do you offer condition surveys and phased budgets?
Yes. A condition survey with a written report is a paid service, guide £180–£360 for a typical single roof, with larger or multi-roof sites priced before we attend. A survey and quote for replacement work is free.
The report covers the covering, upstands, outlets, edges and rooflights, signs of ponding or wet insulation, and what needs doing now, soon and later. You can then plan a phased programme: urgent repairs first, then re-roofing in sections over one or more budget years, with each phase priced separately in your written quote.
Re-covering more than half of a roof over heated space usually triggers the thermal element rules, so the insulation is upgraded towards the renovation U-value where feasible; in England the non-domestic target is 0.18 W/m²K. We handle building control where it is needed. See building regulations and flat roof surveys.
Which towns in London do we cover?
- Westminster
- Camden
- Islington
- Haringey
- Hounslow
- Barnet
- Bexley
- Lambeth
- Croydon
- Havering
- Lewisham
- Redbridge
- Southwark
- Bromley
- Ealing
- Hammersmith and Fulham
- Harrow
- Kensington and Chelsea
- Barking and Dagenham
- Brent
- Greenwich
- Hillingdon
- Kingston upon Thames
- Richmond upon Thames
- Sutton
- Waltham Forest
- Enfield
- Hackney
- Newham
- Tower Hamlets
- Merton
- Wandsworth
Commercial flat roofing in London: questions
Which towns in London do you cover?
All of London. The main towns have their own pages below, and if yours isn't listed we still cover it: send your postcode and we'll confirm.
How much does a commercial flat roof cost in London?
£15,900–£26,150 for a 100 m² commercial roof in single-ply with insulation, at London guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Which postcode areas do you cover in London?
All of London, including the BR, CR, DA, E, EC, EN, HA, IG postcode areas. Send your full postcode and we'll confirm.
What happens to air conditioning units and other roof plant?
Plant can often stay in place, with the new roof detailed around its supports. Where it has to be isolated and lifted, your mechanical contractor does that while we re-roof beneath it, and we agree the timing at survey stage.
Can the cost be spread over more than one budget year?
Yes. We can price a phased programme with each section shown separately, starting with the most urgent areas, so you can plan the spend while the building stays protected.
Do you work on school roofs?
Yes, where the school or its managing body appoints its own contractor. If your procurement rules require a framework contractor, check that before asking us to quote.
Everything about commercial flat roofing → · All flat roofing in London →