Lewisham at a glance
- Postcode districts
- SE6, SE13, SE4, SE23, SE26, SE12, SE10, SE20
- Council area
- London Borough of Lewisham
- Building approval
- London Borough of Lewisham building control, or a registered building control approver
- Guide price region
- London (+20% on West Midlands rates)
Why choose a liquid-applied roof in Lewisham?
For businesses and landlords in Lewisham, a cold-applied liquid roof means no flame on site and, with some systems, a short cure time. That can make it easier to work around occupied buildings, tenants and opening hours than a system that needs hot works or a long strip-out.
Lewisham's flat roofs are mostly on mansion blocks and purpose-built flats with large flat roofs, with plenty on Victorian and Edwardian terraces with flat-roofed back additions too. 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 Lewisham?
Guide price in Lewisham: £2,450–£3,900 for a typical 18 m² garage roof in a liquid-applied system, including VAT at London rates. 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 |
Can a liquid roof go over my existing roof, and what preparation is needed?
Yes, if the existing roof is dry, firmly bonded and sitting on a sound deck. A liquid membrane is only as good as what lies beneath it, so we test the old roof before agreeing to overlay it.
At survey we check for:
- Trapped moisture: soft spots, blisters or wet insulation mean the roof should be stripped, because water sealed in will cause new blisters and decay.
- Deck condition: any sponginess or deflection needs repair first.
- Adhesion: on felt and asphalt, loose areas are cut out and patched, and the existing surface must take the primer properly.
- Falls and ponding: a coating follows the roof as it is. If water ponds now, it will pond on the new surface too unless the falls are corrected.
Preparation then follows: loose chippings removed, the surface cleaned and left to dry, blisters cut back and repaired, cracks filled, and the right primer applied. On older felt, mineral surfaces may need extra cleaning to give a good bond. Where the tests fail, we say so plainly and quote for a strip and re-roof. Read more on ponding water.
What's included?
- Detailing of upstands, outlets, pipes and corners before the main area
- Fleece-reinforced liquid membrane applied to the specified thickness
- Top coat with optional anti-slip finish, and guarantee registration where available
- Primer matched to the substrate
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 Lewisham: questions
Do you cover Lewisham?
Yes. Lewisham is part of our London coverage, including postcode districts SE6, SE13, SE4, SE23, SE26, SE12 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 Lewisham?
Where the work needs approval it goes to London Borough of Lewisham 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 Lewisham?
£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.
What is a fleece-reinforced liquid roof?
It is a liquid membrane with a polyester fleece embedded between coats. The fleece adds strength, helps control thickness and resists cracking where the surface moves slightly.
How long does a liquid roof take to cure?
That depends on the product and the weather. Some systems are rain-resistant within an hour or so, others take longer, and full cure can take a day or more in cool weather.