Grangemouth at a glance
- Postcode districts
- FK3
- Population
- about 16,120 (GeoNames)
- Council area
- Falkirk Council
- Building approval
- Falkirk Council building standards
- Nearest main town
- Falkirk, about 3 miles
- Guide price region
- Scotland (−5% on West Midlands rates)
What makes a good extension roof in Grangemouth?
Rooflights fitted after the roof was built are a frequent source of trouble in Grangemouth extensions. If the kerb was not formed properly or the membrane was simply sealed around the frame, leaks follow. Replacing the roof is the chance to rebuild every upstand to a proper standard.
In a town like Grangemouth, flat roofs are commonly found on terraced streets with flat-roofed rear kitchens and bathrooms or shops with flat-roofed rear stores below flats. Scotland averages roughly 1,570 mm of rain a year, with the west far wetter than the east, so drainage, falls and wind uplift are part of every specification we write.
How much does a new extension roof cost in Grangemouth?
At Scotland guide rates, a 20 m² extension roof in EPDM with a new deck and insulation comes to £2,650–£4,650 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 | £2,650–£4,650 |
| Extension (20 m²), GRP, new deck + insulation | £2,850–£5,100 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £2,850–£4,950 |
| Single garage (18 m²), EPDM rubber | £1,500–£2,650 |
Which flat roof system suits a kitchen extension?
On a plain rectangular extension, EPDM rubber is a strong, quiet choice that can often be laid in one sheet. It handles the slight movement between an extension and the house well.
Where the roof has a lantern, several rooflights or an internal corner, GRP fibreglass forms neat, rigid details around each one. Torch-on felt is a proven layered system and keeps costs down, though near timber cladding or at fragile junctions we may prefer a cold-applied method. If the extension is overlooked from upstairs windows, a sedum green roof is worth considering, provided the structure can take the extra load.
Whatever the membrane, the insulation sits above the deck as a warm roof. Our warm vs cold roof guide explains why.
What's included?
- New abutment upstand and flashing, plus rebuilt rooflight kerbs
- Free survey of the roof, abutment and room below
- Building standards handled where needed, and a written workmanship guarantee
- Staged strip-out so the room stays weathertight
Building standards in Scotland
In Scotland the building standards technical handbooks (Section 6 for energy) apply, and the council's building standards service decides whether a building warrant is needed. Like-for-like repairs to a roof covering can be exempt; alterations, structural work and new roofs usually need a warrant before work starts. The domestic roof benchmark is 0.12 W/m²K, applied as far as reasonably practicable on an existing roof. More on the rules.
Which nearby areas do we also cover?
Extension and kitchen roofs in Grangemouth: questions
Do you cover Grangemouth?
Yes. Grangemouth is part of our Falkirk coverage, including postcode districts FK3. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.
Who checks building standards for a flat roof in Grangemouth?
Where the work needs approval it goes to Falkirk Council building standards. 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 new extension roof cost in Grangemouth?
£2,650–£4,650 for a 20 m² extension roof in EPDM with a new deck and insulation, at Scotland guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can you keep my existing roof lantern?
Often, if the lantern itself is sound. We lift it, rebuild the kerb, dress the new membrane up the upstand and refit the lantern.
Why does my extension ceiling get damp in winter if the roof isn't leaking?
That is often condensation in a cold roof, where warm, moist air reaches the cold underside of the deck. A warm-roof replacement with a vapour control layer usually solves it.