Daventry at a glance
- Postcode districts
- NN11
- Population
- about 28,123 (GeoNames)
- Council area
- West Northamptonshire Council
- Building approval
- West Northamptonshire Council building control, or a registered building control approver
- Nearest main town
- Rugby, about 9 miles
- Guide price region
- East Midlands (−2% on West Midlands rates)
What makes a good extension roof in Daventry?
Selling a house in Daventry with a tired extension roof can raise questions in the buyer's survey. A recent replacement, with building control sign-off where needed and written guarantees, gives a buyer confidence and removes a likely point of negotiation.
Daventry's flat roofs are mostly on 1930s semis with flat-roofed garages and kitchen extensions, with plenty on low-rise post-war blocks of flats too. The East Midlands is drier than the west of Britain, so most flat roofs here fail through age, UV and poor detailing at upstands rather than sheer rainfall.
How much does a new extension roof cost in Daventry?
For Daventry we use East Midlands rates: £2,750–£4,800 is the guide for a 20 m² extension roof in EPDM with a new deck and insulation, VAT included. 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 | £2,750–£4,800 |
| Extension (20 m²), GRP, new deck + insulation | £2,950–£5,300 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £2,950–£5,150 |
| Single garage (18 m²), EPDM rubber | £1,550–£2,750 |
How long will my kitchen be disrupted by a new roof?
Most single-storey extension roofs are replaced in two to four working days, depending on size, rooflights and weather. The kitchen usually stays in use throughout.
Expect noise during the strip-out, and occasional dust through gaps around old rooflights, so it helps to cover worktops and move anything fragile off high shelves. We strip only what we can make weathertight by the end of each day. If a rooflight or lantern is being lifted and refitted, there may be a temporary cover over the opening for a short time. Resin systems smell while they cure, so keep the windows below the roof closed on that day.
What's included?
- Free survey of the roof, abutment and room below
- Building control handled where needed, and a written workmanship guarantee
- Falls set away from the house wall
- Staged strip-out so the room stays weathertight
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?
- Rugby · 9 mi
- Northampton · 12 mi
- Royal Leamington Spa · 15 mi
- Banbury · 15 mi
- Warwick · 18 mi
- Coventry · 18 mi
Extension and kitchen roofs in Daventry: questions
Do you cover Daventry?
Yes. Daventry is part of our Northamptonshire coverage, including postcode districts NN11. 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 Daventry?
Where the work needs approval it goes to West Northamptonshire 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 new extension roof cost in Daventry?
£2,750–£4,800 for a 20 m² extension roof in EPDM with a new deck and insulation, at East Midlands guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
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.
Can a sedum roof go on my extension?
Possibly, if the structure can carry the extra weight and the roof has suitable falls and drainage. We check the joists at survey before recommending it.