- Guide price
- £2,750–£4,800
- Survey
- Free for new and replacement roofs
- Quote
- Fixed, in writing
- Coverage
- England, Wales, Scotland, NI
Powys at a glance
- Largest towns
- Newtown, Brecon
- Postcode areas
- LD, SY
- Building control
- Powys County Council
- Neighbouring areas
- Blaenau Gwent · Ceredigion · Merthyr Tydfil · Torfaen
- Guide price region
- Wales (−8% on West Midlands rates)
How much does a rooflight upstand cost in Powys?
Guide prices including VAT at Wales 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 | £2,750–£4,800 |
| Extension (20 m²), EPDM, new deck + insulation | £2,600–£4,500 |
| Extension (20 m²), EPDM with sedum green roof | £4,050–£7,450 |
Which flat roofs are common in Powys?
Flat roofs in Powys sit on low-rise post-war blocks of flats, terraced streets with flat-roofed rear kitchens and bathrooms and lock-up garage blocks on estates. Wales averages roughly 1,460 mm of rain a year, among the wettest in Britain, so we design for steady run-off: proper falls, clear outlets and upstands well above the finished roof. Approximate 1991–2020 regional averages based on Met Office data.
Building regulations in Wales
Welsh guidance is that most re-roofing needs building control approval, so it's worth checking whenever more than a quarter of a roof is replaced or repaired. Renovated roofs are upgraded to around 0.16 W/m²K where feasible, and new extension roofs are built to 0.13 W/m²K under the Welsh Approved Document L. In Powys the application goes to Powys County 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 Powys do we cover?
Rooflights in flat roofs in Powys: questions
Which towns in Powys do you cover?
All of Powys. 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 Powys?
£2,750–£4,800 for a 20 m² insulated EPDM extension roof with one rooflight upstand, at Wales guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Which postcode areas do you cover in Powys?
All of Powys, including the LD, SY postcode areas. Send your full postcode and we'll confirm.
How high should a flat rooflight upstand be?
Usually at least 150 mm from the finished roof surface to the top of the waterproofing, so the joint stays above standing water. Some rooflight makers specify more.
Can I walk on a flat rooflight?
No, unless it is a unit specifically designed and rated for foot traffic. Treat standard rooflights and the roof around them as fragile.
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 Powys →