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Liquid-applied roofing across Hampshire

Across Hampshire, our vetted teams working under S&K apply reinforced liquid membranes to new decks and to sound existing roofs. Weather varies across the area, so application is planned for dry windows and the cure time of the chosen product. The guide prices here are set for this region, and the survey fixes your own price.

Grey liquid waterproofing and reinforcement fleece rolled around a vent pipe on a flat roofComputer-generated example image
Price per m²
£99–£154
Typical life
10–25+ years by product
Manufacturer guarantees
10, 15 or 20-year guarantees by named system
Typical garage roof
£2,250–£3,600

Hampshire at a glance

Largest towns
Southampton, Portsmouth, Basingstoke, Gosport
Postcode areas
BH, GU, PO, RG, SO, SP
Building control
Southampton City Council, Portsmouth City Council, Basingstoke and Deane Borough Council and 10 other councils
Neighbouring areas
Isle of Wight · Berkshire · West Sussex · Surrey
Guide price region
South East (+10% on West Midlands rates)

How much does a liquid-applied roof cost in Hampshire?

Guide prices including VAT at South East rates. The fixed price comes after a free survey for new and replacement roofs.

JobGuide price inc VAT
Single garage (18 m²), liquid-applied£2,250–£3,600
Balcony (12 m²), liquid-applied, scaffold£2,100–£3,600
Single garage (18 m²), EPDM rubber£1,750–£3,100
Extension (20 m²), EPDM, new deck + insulation£3,100–£5,350

Which flat roofs are common in Hampshire?

Flat roofs in Hampshire sit on low-rise post-war blocks of flats, terraced streets with flat-roofed rear kitchens and bathrooms and newer estates where the first extension roofs are now being replaced. Much of the South East sits in the drier Thames catchment at roughly 730 mm of rain a year, so the usual failures are at joints, upstands and outlets rather than from sheer volume of rain. 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 Hampshire the application goes to Southampton City Council, Portsmouth City Council, Basingstoke and Deane Borough Council and 10 other councils. More on the rules.

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.

How long does a liquid-applied roof last, and how is it guaranteed?

Cold liquid-applied roofs typically last 10 to 25 years or more, depending on the product and the thickness applied. One reinforced system has a BBA assessment of over 25 years, while lighter coatings designed to extend an existing roof sit at the lower end of the range.

Because life varies so much by product, it pays to know exactly what is being applied. Your quote should name the system, the reinforcement and the build-up.

Manufacturer guarantees are often tied to a named system, with lengths such as 10, 15 or 20 years depending on the specification, and some require registration or an approved applicator. We handle that registration where the system permits it. Every re-roof also carries our written workmanship guarantee, with the length set out in the quote, and you can ask about insurance-backed options. A BBA certificate is a product assessment, not a guarantee; our guarantees guide explains the difference.

Which towns in Hampshire do we cover?

Liquid-applied roofing in Hampshire: questions

Which towns in Hampshire do you cover?

All of Hampshire. 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 liquid-applied roof cost in Hampshire?

£2,250–£3,600 for a typical 18 m² garage roof in a liquid-applied system, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.

Which council handles building control for a flat roof in Hampshire?

It depends on where the roof is: in Hampshire that's Southampton City Council, Portsmouth City Council, Basingstoke and Deane Borough Council and 10 other councils. 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. We confirm which applies at the survey.

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.

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.

Is liquid roofing good for balconies?

Often, yes. It forms neatly around railings, door thresholds and drains, and some systems take foot traffic. A new balcony or roof terrace generally needs planning permission, so check before converting a roof.

Everything about liquid-applied roofing → · All flat roofing in Hampshire →

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