- Guide price
- £3,100–£5,400
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
Bristol at a glance
- Largest towns
- Bristol
- Postcode areas
- BS
- Building control
- Bristol City Council
- Neighbouring areas
- Somerset · Gloucestershire · Wiltshire · Herefordshire
- Guide price region
- South West (+3% on West Midlands rates)
How much does a rooflight upstand cost in Bristol?
Guide prices including VAT at South West 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 | £3,100–£5,400 |
| Extension (20 m²), EPDM, new deck + insulation | £2,900–£5,050 |
| Extension (20 m²), EPDM with sedum green roof | £4,550–£8,350 |
Which flat roofs are common in Bristol?
Flat roofs in Bristol sit on shops with flat-roofed rear stores below flats, 1930s semis with flat-roofed garages and kitchen extensions and low-rise post-war blocks of flats. The South West averages roughly 1,260 mm of rain a year and many roofs face wind off the Atlantic, so we specify fixings and edge details for wind uplift as well as drainage. 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 Bristol the application goes to Bristol City Council. More on the rules.
Should I choose a fixed or an opening rooflight, or a lantern?
Choose a fixed rooflight if you only want daylight, an opening one if the room needs ventilation, and a lantern if you want a raised, pitched glazed feature over a larger space.
- Fixed flat rooflights are the simplest and usually the cheapest option. They have the fewest moving seals, and the upstand detail is straightforward.
- Opening rooflights can be manual or electric, and electric units often include a rain sensor that closes them automatically. They need a power supply planned in before the ceiling is finished. Some are designed as hatches to give access to the roof.
- Roof lanterns have a framed, pitched glazed top that brings in more light and adds height to the room. They are heavier and larger, so the upstand has to be strong, level and square, and the joists around the opening may need strengthening.
Whatever you choose, it helps to settle on the unit before the roof is built, so the upstand can be made to the maker's sizes. If you've already chosen one, we build the upstand to suit it.
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.
Which towns in Bristol do we cover?
Rooflights in flat roofs in Bristol: questions
Which towns in Bristol do you cover?
All of Bristol. 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 Bristol?
£3,100–£5,400 for a 20 m² insulated EPDM extension roof with one rooflight upstand, at South West 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 Bristol?
It depends on where the roof is: in Bristol that's Bristol City 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.
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.
Why does my rooflight drip in winter?
If it only drips in cold weather and not when it rains, it is probably condensation on a cold, poorly insulated upstand or older glazing. Better ventilation helps, and an insulated kerb and modern unit usually fix it.
Everything about rooflights in flat roofs → · All flat roofing in Bristol →