Hounslow at a glance
- Postcode districts
- TW3, TW5, TW4, TW7, UB2, TW14, UB1, TW13 and 2 more
- Council area
- London Borough of Hounslow
- Building approval
- London Borough of Hounslow building control, or a registered building control approver
- Guide price region
- London (+20% on West Midlands rates)
Why choose a liquid-applied roof in Hounslow?
If a flat roof in Hounslow 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.
Hounslow's flat roofs are mostly on mansard and dormer loft conversions, with plenty on kitchen extensions and roof terraces behind period houses 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 Hounslow?
For Hounslow 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 |
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?
- Survey of the existing roof, including moisture and adhesion checks
- Top coat with optional anti-slip finish, and guarantee registration where available
- Detailing of upstands, outlets, pipes and corners before the main area
- 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?
- Richmond upon Thames · 3 mi
- Ealing · 4 mi
- Kingston upon Thames · 5 mi
- Hammersmith and Fulham · 6 mi
- Hillingdon · 7 mi
- Brent · 7 mi
Liquid-applied roofing in Hounslow: questions
Do you cover Hounslow?
Yes. Hounslow is part of our London coverage, including postcode districts TW3, TW5, TW4, TW7, UB2, TW14 and 4 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 Hounslow?
Where the work needs approval it goes to London Borough of Hounslow 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 Hounslow?
£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.
Does a liquid roof smell when it is applied?
Some systems, particularly PMMA, have a strong odour during application, while many polyurethane and water-based products are milder. We tell you what to expect and plan around windows and vents.
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.