A flat roof replacement strips the old covering from a low-pitched roof and lays a new waterproof system, usually EPDM rubber, GRP fibreglass or torch-on felt, over a sound deck with correct falls, upstands, trims and outlets so rainwater drains away.
Every house in Amersham is a little different, so we never price a new flat roof from a brochure. We look at the structure, access and existing finishes first, then put in writing a fixed figure for the scope we settle on. As a rough steer, homeowners in the South East should budget £2,200–£5,000 including VAT, with work typically taking 1–3 days for most roofs.
- Guide price
- £2,200–£5,000 inc VAT
- Time on site
- 1–3 days for most roofs
- Postcodes
- HP6 and HP7
- Planning rules
- England
- Local area
- Buckinghamshire
- Survey
- Free, with a written quote
What should you budget for a new flat roof in Amersham?
What will a new flat roof cost in Amersham? Our guide range is £2,200–£5,000 including VAT. That figure is adjusted for the South East, about 12% above the national guide, and is intended for planning a budget. A firm written price for your chosen specification follows a free survey at your home.
| Type of job | What it usually involves | Guide in Amersham |
|---|---|---|
| Small roof (up to 8m²) | A dormer, bay, porch or small garage roof re-covered in EPDM or GRP. | £900–£2,200 |
| Extension or garage (15–25m²) | A typical extension or single garage roof stripped and re-covered. | £2,200–£5,000 |
| Large or new warm roof | Larger roofs, or roofs needing a new deck and insulation build-up. | £4,500–£10,000 |
Expect these to shape the final quote:
- Covering system: EPDM, GRP or torch-on felt
- Condition of the deck and joists underneath
- Insulation upgrades and changes to roof height at edges
- Number of rooflights, pipes and upstands to detail
Scope of the work
- Survey of the covering, deck, falls, upstands and drainage
- Stripping and disposal of the old roof covering
- Insulation upgrade to a warm roof build-up where agreed
- New EPDM, GRP or torch-on felt membrane laid to falls
- Upstands, flashings and drip edges finished neatly
- New trims, outlets and gutter connections
What are homes like around Amersham?
Buckinghamshire runs from Chiltern villages of brick and flint, through Metroland interwar semis around Amersham and Chesham, to Victorian terraces in High Wycombe and Aylesbury. Milton Keynes adds estates built from the 1970s onwards in brick, render and timber frame, and new housing continues to spread around its edges.
The Chiltern hills are more exposed than the vale below, and clay-with-flints soils make drainage design and footing depth worth checking early.
If your house in Amersham fits one of these patterns, it helps us anticipate what a new flat roof will involve, though we always confirm the details on site.
Planning and building rules in Amersham
The notes below cover England, which is where Amersham sits. Rules change and every property is different, so we speak to the council before pricing your job.
Re-roofing a house with similar materials does not usually need planning permission in England. Listed buildings and conservation areas may need consent if the covering changes.
Replacing more than a quarter of a roof’s covering counts as renovation under Building Regulations, so the work is notified and the roof insulation may need upgrading. Bats are protected across the UK; if they roost under roof tiles, soffits or fascias, work stops and a licensed ecologist advises before it restarts.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
The four stages
We look at the job
Book a visit and we'll come to you. The survey covers measurements, the state of what's there now and any obvious constraints, so the price that follows is based on your actual home, not an average.
Your fixed price
You get the price in writing, itemised so you can see where the money goes. As long as the specification stays the same, that is the price you pay for a new flat roof.
Getting ready
Before anyone starts, we confirm the programme in writing, check whether consents are required and arrange deliveries. If a skip or scaffolding on the road needs a permit, we apply for it.
The work itself
On site, the agreed plan is followed and any change is put in writing first. At completion we do a final clean, go through the snagging list with you and leave you with the relevant documents.
What you can expect from us
Frequently asked questions
Can you combine a new flat roof with other work?
Yes. Because we manage several trades under one contract, we can plan a new flat roof alongside other work on your Amersham home, such as new windows with rendering, or a kitchen refit with an extension. Combining jobs can reduce repeat set-up such as scaffolding, skips and access, and every element is listed and priced in the same written quote.
Can you repair my flat roof instead of replacing it?
A flat roof can often be repaired if the damage is limited to a small split, a failed joint or a loose upstand and the rest of the covering is sound. If the deck is soft, the covering is blistered or cracked across the roof, or leaks keep returning, replacement is usually better value. We assess the whole roof and give you an honest recommendation.
Which is better, EPDM rubber or GRP fibreglass?
EPDM rubber and GRP fibreglass are both reliable modern flat roof systems. EPDM is a single flexible sheet with very few joints, which copes well with movement and suits most extensions and garages. GRP is a hard, seamless finish that copes better with foot traffic and complex shapes, but needs dry weather to apply. Felt costs less but usually lasts less long. We recommend a system after seeing your roof.
Is a flat roof suitable for a roof terrace?
A flat roof can only be used as a terrace if it is designed for it, with joists strong enough for people and furniture, a hard-wearing surface, safe edge protection and correct drainage. Using a standard extension roof as a terrace can damage it and may need planning permission and building regulations approval. We can advise on what a conversion would involve.
How long will a new flat roof take?
On a typical home, allow 1–3 days for most roofs. Larger projects, older buildings and extra work found once things are opened up can extend that, while simpler jobs may be shorter. Your quote includes an estimate of time on site, and your point of contact keeps you updated on the programme as the work progresses.
Near Amersham
We survey and quote throughout Amersham's HP6 and HP7 postcodes and in surrounding places such as Chesham, Chalfont Saint Peter and Gerrards Cross. The process and pricing approach are identical in each of them.