Crowthorne at a glance
- Postcode districts
- RG45
- Population
- about 25,522 (GeoNames)
- Council area
- Wokingham Borough Council
- Building approval
- Wokingham Borough Council building control, or a registered building control approver
- Nearest main town
- Bracknell, about 3 miles
- Guide price region
- South East (+10% on West Midlands rates)
Why upgrade to a warm roof in Crowthorne?
Many flat-roofed extensions and dormers in Crowthorne were built with little or no insulation, or with a cold roof that was never properly ventilated. Those rooms are often hard to heat in winter and can suffer condensation, mould and, in time, a rotten deck.
Around Crowthorne, flat roofs are common on 1960s and 1970s link-detached houses with flat-roofed garages and porches and on 1930s semis with flat-roofed garages and kitchen extensions. 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.
How much does a warm roof upgrade cost in Crowthorne?
For Crowthorne we use South East rates: £3,100–£5,350 is the guide for a 20 m² extension roof in EPDM with a new deck and insulation, VAT included. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM, new deck + insulation | £3,100–£5,350 |
| Extension (20 m²), EPDM with sedum green roof | £4,850–£8,900 |
Can a cold flat roof be converted to a warm roof?
Yes, and it is the usual approach when an older cold roof is re-covered. The old covering is stripped, the deck is checked and replaced where needed, and the vapour control layer, insulation and new waterproofing go on top.
The existing insulation between the joists is assessed at the same time. Leaving it in place can create a cold, unventilated gap that traps moisture, so it is often removed or the build-up is designed so that most of the insulation sits above the deck. We decide this case by case once we can see inside the roof. If the covering is still sound and you are only patching it, the upgrade isn't usually required, and our repair or replace guide explains how to decide between the two.
What's included?
- Building control or building standards handled where needed
- Rigid insulation boards sized to the U-value target
- New waterproofing, with a written workmanship guarantee
- Vapour control layer on the warm side of the insulation
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?
Warm roof insulation upgrades in Crowthorne: questions
Do you cover Crowthorne?
Yes. Crowthorne is part of our Berkshire coverage, including postcode districts RG45. 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 Crowthorne?
Where the work needs approval it goes to Wokingham Borough Council 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 warm roof upgrade cost in Crowthorne?
£3,100–£5,350 for a 20 m² extension roof in EPDM with a new deck and insulation, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Will a warm roof make my room warmer?
Usually, yes. A room under a poorly insulated flat roof loses less heat once the roof is upgraded and tends to feel more even in temperature. How much difference you notice depends on how the roof was built before.
Does a warm roof stop condensation?
It greatly reduces the risk by keeping the deck warm and placing a vapour control layer on the warm side. Good ventilation in kitchens and bathrooms below still helps.