Flat rooflights in Greenwich: what is involved?
We handle flat rooflights across Greater London, including Greenwich. In short: fixed double or triple glazed rooflights for flat roofs and extensions. The survey checks structure, weathering and orientation, so the quote reflects your actual roof.
Party walls are a fact of life in London terraces, and rooflights close to a shared wall need detailing that keeps the neighbour's side dry too. Think of flat rooflights for landings, bathrooms and rear extensions with flat roofs.
From Greenwich to Blackheath, Lewisham and Catford, the same survey-first process applies: measure, specify, fix the price, then fit.
What you can choose
- Insulated kerb or timber upstand built to suit
- Frame colours: anthracite, black, white or RAL
- Integral or fitted blinds
- Solar-control or self-cleaning outer pane
- Rain sensor if paired with an opening unit
- Pairs with an opening unit where you also need ventilation
- Fixed units are simple, quiet and low-maintenance
Things we check at survey
- Rooflights count toward glazing in an extension, which matters for Building Regulations energy and overheating rules
- Needs a properly formed upstand — usually at least 150 mm above the finished roof surface (check the manufacturer's figure)
Planning and building rules for Greenwich
English householder permitted development (Class C) normally covers rooflights that stand no more than 0.15 m proud of the roof plane and stay below the highest part of the roof. Listed buildings need listed building consent, flats have no householder permitted development rights, and an Article 4 direction can remove the rights in some conservation areas.
Under Approved Document L, a rooflight added to an English home must achieve at least 2.2 W/m²K (horizontal plane), and a roof window 1.4 W/m²K or Window Energy Rating Band B. Replacing a rooflight or roof window can be self-certified by an installer registered with an authorised competent person scheme; otherwise building control approval is needed.
See our building regulations guide for U-values, glazing limits and self-certification.
What do flat rooflights cost in Greenwich?
Prices below are shown including and excluding VAT. In Greenwich, as elsewhere, making good inside and access equipment are the main variables.
| Option | Guide price inc VAT | Ex VAT |
|---|---|---|
| Large or triple glazed (1500 × 2500 mm and up) | £2,395 – £4,195 | £1,995 – £3,495 |
| Mid-size double glazed (1000 × 2000 mm) Typical | £1,675 – £2,395 | £1,395 – £1,995 |
| Small double glazed (up to 1000 × 1000 mm) | £1,195 – £1,795 | £995 – £1,495 |
From enquiry to finished job
- Send the details. Postcode, rough size and a photo of the roof and room.
- Measure and check. A surveyor visits Greenwich, measures and checks structure and access.
- Written price. You receive a fixed price listing the unit, the work and the lead time.
- Fit and make good. We fit, seal, test and finish the reveal, then hand over the paperwork.
Flat rooflights near Greenwich
More we do in Greenwich
Flat rooflights in Greenwich: questions
Do flat rooflights leak?
A well-fitted flat rooflight should not leak. Leaks almost always come from the upstand or membrane detailing, not the glass unit, which is why the upstand height and the way the roof covering is dressed up and under the frame matter more than the brand.
Can you fit into my existing flat roof?
Yes. We form a new opening, trim the joists, build and waterproof an upstand and make good the ceiling. A survey confirms the joist direction and roof build-up first.
Double or triple glazing?
Double glazing suits most domestic jobs. Triple glazing improves thermal performance and cuts noise from rain, which is worth it over bedrooms or where the energy calculation is tight.
Can you work alongside my builder in Greenwich?
Yes. On new extensions we fit once the opening and upstand are ready and coordinate dates with your builder.
Do I need to be at home for the survey in Greenwich?
Yes — someone needs to let us into the room below and, where possible, show us how the roof is reached.
