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.
From a first conversation about a new flat roof to the day the site is cleared, homeowners in St Albans deal with us directly. We come out to measure up at no cost, explain the choices in plain terms and send a written quote. For context, comparable work in the East of England usually falls within £2,100–£4,700 including VAT, and it is available across AL1 and AL2.
- Guide price
- £2,100–£4,700 inc VAT
- Time on site
- 1–3 days for most roofs
- Postcodes
- AL1 and AL2
- Planning rules
- England
- Local area
- Hertfordshire
- Survey
- Free, with a written quote
What should you budget for a new flat roof in St Albans?
Here is how the guide price for a new flat roof breaks down in St Albans. We start from national figures and adjust for the East of England, which comes out about 5% above the national guide. The resulting range, VAT included, is £2,100–£4,700, and a survey, at no cost to you, firms it up.
| Type of job | What it usually involves | Guide in St Albans |
|---|---|---|
| Small roof (up to 8m²) | A dormer, bay, porch or small garage roof re-covered in EPDM or GRP. | £850–£2,100 |
| Extension or garage (15–25m²) | A typical extension or single garage roof stripped and re-covered. | £2,100–£4,700 |
| Large or new warm roof | Larger roofs, or roofs needing a new deck and insulation build-up. | £4,200–£9,400 |
The main things that change the figure:
- Roof area and access to the roof
- Covering system: EPDM, GRP or torch-on felt
- Insulation upgrades and changes to roof height at edges
- Number of rooflights, pipes and upstands to detail
What does the job include in St Albans?
- Survey of the covering, deck, falls, upstands and drainage
- Stripping and disposal of the old roof covering
- Replacement of rotten or soft deck boards
- 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
What are homes like around St Albans?
Hertfordshire is home to the first garden cities, Letchworth and Welwyn Garden City, and the post-war new towns of Stevenage, Hatfield and Hemel Hempstead. Watford and St Albans have Victorian terraces and Georgian streets, interwar semis line the commuter suburbs, and brick-and-flint cottages appear in Chiltern villages to the west.
Generally dry with chalk and clay soils; clay areas can move in long dry spells, and mature trees near houses need considering for foundations.
So when we survey a St Albans property for a new flat roof, the first step is working out how it was built and what has been changed since.
Planning and building rules in St Albans
Each UK nation sets its own consent rules, and St Albans is in England. What follows is a plain summary; we check the specifics for your property with the council before pricing anything.
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
Survey and measure
First, someone visits your home in St Albans to see the space, take measurements and note anything that could affect the work, such as access or the condition of what is there. There is no charge for this visit.
Your fixed price
We put everything into a written, fixed-price quote: the specification, what's excluded, staged payments and the expected time on site. Take whatever time you need to decide; there's no pressure to commit.
Getting ready
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for a new flat roof are in place before the first day on site.
On site to finish
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.
How we work
Frequently asked questions
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.
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 St Albans 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.
How much will a new flat roof cost in St Albans?
As a guide, expect to pay £2,100–£4,700 including VAT for a new flat roof in St Albans. That range is adjusted for the East of England, which runs about 5% above the national guide. Where your project lands depends on size, materials, access and the condition of what is already there. We confirm a fixed price in writing after a free survey of your home.
How long does a flat roof last?
A well-installed EPDM or GRP flat roof can last 25 years or more, while torch-on felt systems typically last around 15–25 years, depending on quality and exposure. Lifespan depends on correct falls, good detailing at edges and upstands, and keeping outlets clear. Foot traffic, ponding and poor ventilation shorten it. Annual checks help catch small problems early.
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.
Also covering areas around St Albans
We welcome enquiries from all AL1 and AL2 postcodes in St Albans, plus Harpenden, Hatfield and Hemel Hempstead. Each one gets the same survey at no charge and a written price fixed for the work described.

