Southwark at a glance
- Postcode districts
- SE5, SE15, SE17, SE22, SE14, SE11, SE1, SE8
- Council area
- London Borough of Southwark
- Building approval
- London Borough of Southwark building control, or a registered building control approver
- Guide price region
- London (+20% on West Midlands rates)
Why choose a liquid-applied roof in Southwark?
If a flat roof in Southwark is ageing but still dry, firmly bonded and on a sound deck, a reinforced liquid system can be applied over it. That avoids the cost and mess of a full strip-out, provided the moisture and adhesion checks at survey show the existing roof is fit to build on.
Around Southwark, flat roofs are common on Victorian and Edwardian terraces with flat-roofed back additions and on kitchen extensions and roof terraces behind period houses. 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.
How much does a liquid-applied roof cost in Southwark?
For Southwark we use London rates: £2,450–£3,900 is the guide for a typical 18 m² garage roof in a liquid-applied system, VAT included. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Single garage (18 m²), liquid-applied | £2,450–£3,900 |
| Balcony (12 m²), liquid-applied, scaffold | £2,300–£3,900 |
| Single garage (18 m²), EPDM rubber | £1,900–£3,350 |
| Extension (20 m²), EPDM, new deck + insulation | £3,350–£5,850 |
Do building regulations apply if a liquid coating goes over my roof?
They can. In England, Wales and Northern Ireland, re-covering more than half of a roof over a heated room is usually renovation of a thermal element, even when the new membrane goes over the old, so the roof should be insulated towards the renovation standard where feasible; for a Scottish property, the local building standards team will confirm whether a warrant is required.
A minor coating repair to a small area is different from re-covering the whole roof. Where insulation is needed, an overlay is not always practical, because the insulation has to go under a new waterproof layer. In that case we may recommend stripping to the deck, fitting a warm roof and applying the liquid system on top. Where approval applies, we deal with the paperwork; details are on the building regulations page.
What's included?
- Fleece-reinforced liquid membrane applied to the specified thickness
- Surface cleaning, repairs and removal of loose material
- Top coat with optional anti-slip finish, and guarantee registration where available
- Survey of the existing roof, including moisture and adhesion checks
Building regulations in England
Replacing more than half of a flat roof over a heated room usually counts as renovating a thermal element, so the roof is insulated to around 0.16 W/m²K where that's technically and economically feasible, and the work is notified to building control: the council or a registered building control approver, unless a registered competent person self-certifies it. A roof on a new extension is built to 0.15 W/m²K. Patch repairs, and most unheated detached garages, don't trigger the upgrade. Structural changes, or a new covering that adds 15% or more to the roof's weight, also need approval. More on the rules.
Which nearby areas do we also cover?
Liquid-applied roofing in Southwark: questions
Do you cover Southwark?
Yes. Southwark is part of our London coverage, including postcode districts SE5, SE15, SE17, SE22, SE14, SE11 and 2 more. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.
Who checks building regulations for a flat roof in Southwark?
Where the work needs approval it goes to London Borough of Southwark building control, or a registered building control approver. We tell you at the survey whether your job needs it and deal with the paperwork as part of the quote.
How much does a liquid-applied roof cost in Southwark?
£2,450–£3,900 for a typical 18 m² garage roof in a liquid-applied system, at London guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can liquid roofing stop a leak on a flat roof?
It can, if the leak is at a detail or the membrane is worn but the roof beneath is sound. If water has soaked the insulation or deck, coating over it will not cure the problem.
Is liquid roofing the same as a roof paint?
No. A proper liquid-applied membrane is built to a specified thickness and usually reinforced with fleece, while roof paints and simple coatings are much thinner and mainly used to extend the life of an existing covering.