- Guide price
- £1,550–£2,900
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
Kent at a glance
- Largest towns
- Maidstone, Gillingham, Royal Tunbridge Wells, Folkestone
- Postcode areas
- BR, CT, DA, ME, TN
- Building control
- Maidstone Borough Council, Medway Council, Tunbridge Wells Borough Council and 10 other councils
- Neighbouring areas
- Essex · London · East Sussex · Surrey
- Guide price region
- South East (+10% on West Midlands rates)
How much does a new dormer roof cost in Kent?
Guide prices including VAT at South East rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Dormer (8 m²), GRP, scaffold | £1,550–£2,900 |
| Single garage (18 m²), EPDM rubber | £1,750–£3,100 |
| Extension (20 m²), GRP, new deck + insulation | £3,300–£5,900 |
Which flat roofs are common in Kent?
Flat roofs in Kent sit on terraced streets with flat-roofed rear kitchens and bathrooms, 1930s semis with flat-roofed garages and kitchen extensions and shops with flat-roofed rear stores below flats. 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. Approximate 1991–2020 regional averages based on Met Office data.
Building regulations in England
Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. Renovated roofs over heated rooms are insulated to around 0.16 W/m²K where that's feasible, and new extension roofs are built to 0.15 W/m²K. In Kent the application goes to Maidstone Borough Council, Medway Council, Tunbridge Wells Borough Council and 10 other councils. More on the rules.
Is GRP or EPDM better on a dormer roof?
GRP fibreglass is often the first choice on a dormer, because it is laid as a liquid resin over a mat and forms neat, rigid edges, corners and drip details on a small roof. It cures to a hard surface that copes with occasional foot traffic during window cleaning or maintenance.
EPDM rubber works well on a plain rectangular dormer and can usually be laid as one sheet, with no field joins. Unlike GRP, it does not depend on resin curing conditions on the day. Torch-on felt can be used, but working a torch close to timber cladding, fascias and tiles needs extra care, so a cold-applied system is often chosen instead.
We recommend the system after surveying the dormer, its edges and how it meets the main roof.
How long does a dormer roof replacement take?
The roofing itself typically takes one to three days, with scaffold going up before and coming down after. Allow a few extra days overall for the scaffold.
The room under the dormer stays usable, though it will be noisy during the strip-out, and dust can fall through gaps around the ceiling. Moving furniture away from the window helps. Scaffold usually needs space on the drive or garden, and sometimes a pavement licence. GRP has a strong smell while it cures, so keep the dormer windows shut on the day it is laid.
Which towns in Kent do we cover?
- Maidstone
- Gillingham
- Royal Tunbridge Wells
- Folkestone
- Margate
- Ashford
- Canterbury
- Sittingbourne
- Gravesend
- Dartford
- Ramsgate
- Dover
- Tonbridge
- Strood
- Whitstable
- Deal
- Sevenoaks
- Herne Bay
- Broadstairs
- Faversham
- Swanley
- Longfield
- Swanscombe
Dormer roofs in Kent: questions
Which towns in Kent do you cover?
All of Kent. The main towns have their own pages below, and if yours isn't listed we still cover it: send your postcode and we'll confirm.
How much does a new dormer roof cost in Kent?
£1,550–£2,900 for an 8 m² GRP dormer roof including scaffold, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Which council handles building control for a flat roof in Kent?
It depends on where the roof is: in Kent that's Maidstone Borough Council, Medway Council, Tunbridge Wells Borough Council and 10 other councils. Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. We confirm which applies at the survey.
How long does a GRP dormer roof last?
As an indicative range, GRP lasts 20–40 years with good specification and maintenance.
Does the room below need emptying?
No, but moving furniture away from the window and covering the floor is sensible. The room stays usable throughout.
Can a dormer roof be replaced without scaffold?
Rarely. A tower or full scaffold is usually needed to give a safe working platform and edge protection at that height.
Everything about dormer roofs → · All flat roofing in Kent →