Greenford · Greater London
Roof Lanterns in Greenford
If your skylight in Greenford drips with condensation or leaks around the frame, we can survey it and quote for a modern, thermally broken replacement.
- UB6
- UB1
- UB5
- Guide from £1,095
About flat roof skylight in Greenford
Warm, moist air rises and collects in a roof lantern, so condensation can form on cold winter mornings, especially over kitchens and bathrooms. Thermally broken frames, warm-edge spacers and good room ventilation reduce it, and opening vents in the lantern can release warm air in summer.
A roof lantern is assembled from an aluminium ridge, hip bars and glazing bars that hold sealed glass units on each pitch. It sits on an upstand built around the roof opening. The upstand should be level, weathered into the roof covering and insulated, because a poor upstand causes most leaks and cold spots.
Roof lanterns are not designed to be walked on, so never stand or lean on the glass or bars. Cleaning and inspection should be done from safe access at the edge of the roof. Keep leaves and debris away from the upstand and roof outlets so water drains freely.
Cutting a new opening for a roof lantern or skylight usually means trimming joists or rafters, so the roof can carry the load around the hole. Building regulations approval is generally needed for a new rooflight, covering structure, energy performance and, near a boundary, fire performance.
What's included
- Survey of the roof, opening, upstand and drainage
- Written guarantee terms and manufacturer documentation
- Fixing, glazing and sealing onto the prepared upstand
- Removal and disposal of an old lantern or skylight

Local details for Greenford
- Postcodes covered
- UB6, UB1, UB5 and the surrounding area, including Northolt, Southall and Ealing
- Coast
- Greenford is well inland, around 51 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Greenford the midwinter sun reaches about 15° above the horizon at noon, with roughly 7.6 hours of daylight, rising to about 62° and 16.4 hours in midsummer. Overhead glazing receives far more light than a wall window of the same size, especially when the sun is high in summer. South-facing lanterns may need solar-control glass, while low winter sun and north-facing rooms benefit from clear, high light-transmission low-E glass.
- Access and setting
- Rural roofs collect more leaves, moss and bird debris, so lanterns need clear upstand drainage and regular checks. Exposed sites see higher wind loads and driving rain, and older outbuildings may need the roof structure strengthening before a lantern is added.
- Rules in England
- Approved Document K requires safety glass in critical locations in England: glazing in doors and in side panels within 300 mm of a door, up to 1500 mm above floor level, and any glazing in walls or partitions up to 800 mm above floor level.
Guide prices in Greenford
| Typical job | Guide price inc VAT |
|---|---|
| Lantern 1500 × 1000 mm, fitted to a kerb | £1,395 – £1,795 |
| Lantern 2000 × 1000 mm | £1,695 – £2,095 |
| Lantern 3000 × 1500 mm | £2,795 – £3,695 |
| Flat glass rooflight 1000 × 1000 mm | £1,095 – £1,395 |
Get a guide price for your size
In England, replacing a whole window, roof window or glazed external door is building work. It has to be notified to building control, either by an installer registered with a competent person scheme such as FENSA or Certass, or through a building notice to the council. Replacing only the glass in an existing frame is a repair and is not notifiable.
Choosing your roof lanterns
Opening vents
Manual or electric vents in the lantern or skylight, with optional rain sensors that close them automatically in wet weather.
Flat framed skylight
A low-profile framed rooflight on a flat roof upstand, fixed or opening, for bathrooms, landings and smaller rooms.
Frame colours
Powder-coated aluminium in grey, black, white or other RAL colours, often dual colour to suit the roof and the room.
Roof Lanterns in Greenford: questions
How much does a roof lantern cost?
The cost of a roof lantern depends on its size and shape, the glass specification, frame colour, any opening vents, and whether the upstand exists or needs building. Access to the roof and lifting a large lantern also affect labour. See the guide prices for typical ranges; the written quote fixes the price for your exact specification.
Do I need planning permission for a roof lantern?
Sometimes. In England, rooflights on a house are usually permitted development if they project no more than 150mm above the roof plane and are no higher than the highest part of the roof. Raised lanterns often exceed that, and flats, listed buildings and conservation areas have extra controls, so check with your council first.
How long does it take to fit a roof lantern?
Fitting a roof lantern on a prepared upstand usually takes a day or less for a typical size, longer for large or complex shapes. The lantern is made to order first, and the lead time depends on its size, shape and colour. Building or rebuilding an upstand is separate roofing work that comes before fitting.
Can I replace my old polycarbonate roof lantern with glass?
Yes, in most cases. A glass lantern is heavier than polycarbonate, so the upstand and roof structure must be able to carry it. If the upstand is sound, level and the right size, a new aluminium lantern can usually sit on it. If not, the upstand is rebuilt first, which the survey will identify.
Do you cover Greenford for roof lanterns?
Yes. We can quote for roof lanterns across Greenford and the surrounding Greater London area, including postcode districts UB6, UB1 and UB5, and nearby Northolt, Southall and Ealing. Start with your postcode on the quote form and a glazier will arrange a free survey before giving you a written quote.
Get a written quote in Greenford
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.