Gerrards Cross at a glance
- Postcode districts
- SL9
- Population
- about 20,633 (GeoNames)
- Council area
- Buckinghamshire Council
- Building approval
- Buckinghamshire Council building control, or a registered building control approver
- Nearest main town
- Slough, about 6 miles
- Guide price region
- South East (+10% on West Midlands rates)
When should a flat roof in Gerrards Cross be replaced?
Flat roofs in Gerrards Cross get replaced for the same reasons as anywhere else: the covering has reached the end of its service life, leaks keep returning after repairs, or water ponds because the deck has sagged. Once the boards are soft or the insulation is wet, a full strip usually costs less than another round of patching.
In a town like Gerrards Cross, flat roofs are commonly found on terraced streets with flat-roofed rear kitchens and bathrooms or 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 flat roof replacement cost in Gerrards Cross?
At South East guide rates, a 20 m² extension roof in EPDM with a new deck and insulation comes to £3,100–£5,350 including VAT. 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 |
| Single garage (18 m²), torch-on felt | £1,650–£2,900 |
| Extension (20 m²), GRP, new deck + insulation | £3,300–£5,900 |
| Single garage (18 m²), EPDM rubber | £1,750–£3,100 |
How long does it take to replace a flat roof?
A garage or single-storey extension roof is usually stripped and re-covered in one to three working days; larger, higher or more detailed roofs take longer. Weather sets the pace, because the deck must be dry before insulation and membrane go down.
We strip only as much as can be made weathertight that day, so the roof is never left open overnight. Expect noise and some vibration during the strip, a skip on the drive (or on the road with a permit) and ladders or a tower against the house. Rooms below stay usable, though it helps to clear shelves near the ceiling. Resin systems such as GRP smell strongly while they cure, so keep nearby windows closed that day. Two-storey roofs need scaffold, which goes up before we start and comes down after sign-off.
What's included?
- Strip-out of the old covering, with waste and skip
- Free survey of the deck, falls, edges and insulation
- New deck, firrings and warm-roof insulation where needed
- New membrane, upstands, edge trims and outlets
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?
- Chalfont Saint Peter · 2 mi
- Rickmansworth · 5 mi
- Slough · 6 mi
- Amersham · 6 mi
- Windsor · 7 mi
- Chesham · 8 mi
Flat roof replacement in Gerrards Cross: questions
Do you cover Gerrards Cross?
Yes. Gerrards Cross is part of our Buckinghamshire coverage, including postcode districts SL9. 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 Gerrards Cross?
Where the work needs approval it goes to Buckinghamshire 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 flat roof replacement cost in Gerrards Cross?
£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 replacement make my roof higher?
Usually a little, if insulation is added above the deck. We check door thresholds, window sills, upstands and wall flashings at survey so the new level works.
Do I need to be at home while the roof is replaced?
Not for most of the job, as long as the team can reach the roof and there is room for a skip. We ask you to be there at the start to agree the plan and at the end to look over the finished roof.