Slough at a glance
- Postcode districts
- SL1, SL2, SL3
- Population
- about 164,793 (GeoNames)
- Council area
- Slough Borough Council
- Building approval
- Slough Borough Council building control, or a registered building control approver
- Nearest main town
- Reading, about 17 miles
- Guide price region
- South East (+10% on West Midlands rates)
Why upgrade to a warm roof in Slough?
Kitchen extensions in Slough, as elsewhere, produce a lot of moisture from cooking. Under a cold flat roof, that moisture can condense on the deck. A warm roof keeps the deck warm and puts a vapour control layer in the way, which lowers the risk considerably.
Around Slough, flat roofs are common on 1930s semis with flat-roofed garages and kitchen extensions and on 1960s and 1970s link-detached houses with flat-roofed garages and porches. 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 Slough?
Guide price in Slough: £3,100–£5,350 for a 20 m² extension roof in EPDM with a new deck and insulation, including VAT at South East rates. 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?
- Survey of the deck, joists and existing insulation
- Building control or building standards handled where needed
- Rigid insulation boards sized to the U-value target
- 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?
- Windsor · 2 mi
- Maidenhead · 5 mi
- Gerrards Cross · 6 mi
- Egham · 6 mi
- Staines-upon-Thames · 7 mi
- Chalfont Saint Peter · 7 mi
Warm roof insulation upgrades in Slough: questions
Do you cover Slough?
Yes. Slough is part of our Berkshire coverage, including postcode districts SL1, SL2, SL3. 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 Slough?
Where the work needs approval it goes to Slough 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 Slough?
£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.
Can you insulate a flat roof from inside instead?
It is possible, but insulating between or under the joists creates a cold roof, which needs ventilation and carries a higher condensation risk. When the roof is being re-covered anyway, a warm roof from above is usually the better option.
Is a warm roof worth it on a garage?
On a detached, unheated garage, usually not, as there is no heated space to protect and the thermal rules don't normally apply. On an integral or heated garage, or one being converted into a room, it is.