- Guide price
- £2,950–£5,150
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
Northamptonshire at a glance
- Largest towns
- Northampton, Corby, Kettering, Wellingborough
- Postcode areas
- NN
- Building control
- West Northamptonshire Council and North Northamptonshire Council
- Neighbouring areas
- Leicestershire · Bedfordshire · Warwickshire · Cambridgeshire
- Guide price region
- East Midlands (−2% on West Midlands rates)
How much does a rooflight upstand cost in Northamptonshire?
Guide prices including VAT at East Midlands rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £2,950–£5,150 |
| Extension (20 m²), EPDM, new deck + insulation | £2,750–£4,800 |
| Extension (20 m²), EPDM with sedum green roof | £4,300–£7,900 |
Which flat roofs are common in Northamptonshire?
Flat roofs in Northamptonshire sit on 1930s semis with flat-roofed garages and kitchen extensions, low-rise post-war blocks of flats and terraced streets with flat-roofed rear kitchens and bathrooms. 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. 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 Northamptonshire the application goes to West Northamptonshire Council and North Northamptonshire Council. More on the rules.
Why is my flat rooflight leaking, and should it be repaired or replaced?
Most rooflight leaks come from the upstand detail rather than the glass: the membrane has split or pulled away at a corner, the upstand is too low, or the flashing at the top has failed. Repair the detail if the unit and the roof around it are sound.
Drips on the inside of the upstand in cold weather may be condensation rather than a leak, especially on older, uninsulated kerbs or single-glazed domes. Warm, moist air from a kitchen or bathroom meets the cold surface and condenses.
If the roof covering is near the end of its life, it is usually better to rebuild the upstand properly as part of a replacement, ideally with a new insulated kerb, rather than patching the old detail. Our repair or replace guide and flat roof repairs page cover the options.
How long does a rooflight upstand last?
A properly built, insulated upstand with waterproofing dressed to the maker's details should last as long as the roof covering around it. The rooflight's own seals and opening parts may need attention sooner.
Upstands fail early when they are too low, poorly insulated or built on a deck that moves. Keeping the area around the rooflight clear of leaves and debris, checking the corners after storms from a safe position and cleaning the glazing gently all help. Never lean on or stand on a rooflight: most are fragile, and the roof around them should be treated as fragile too. The maintenance guide covers routine checks.
Which towns in Northamptonshire do we cover?
Rooflights in flat roofs in Northamptonshire: questions
Which towns in Northamptonshire do you cover?
All of Northamptonshire. 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 rooflight upstand cost in Northamptonshire?
£2,950–£5,150 for a 20 m² insulated EPDM extension roof with one rooflight upstand, at East Midlands 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 Northamptonshire?
It depends on where the roof is: in Northamptonshire that's West Northamptonshire Council and North Northamptonshire Council. 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.
Can a lantern go on a warm roof?
Yes. The upstand is built and insulated to the full height of the warm roof build-up, so the lantern sits at the right level above the finished surface.
Will an opening rooflight let rain in if I leave it open?
Many electric opening rooflights include a rain sensor that closes them automatically when it starts raining. With manual units, it's up to you to close them.
Do you supply rooflights and lanterns?
We fit rooflights and lanterns as part of a flat roof job, but we don't sell them as a separate product. If you've chosen a unit, we'll build the upstand to suit it.
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