Eltham · Greater London
Roof Lanterns in Eltham
If your skylight in Eltham drips with condensation or leaks around the frame, we can survey it and quote for a modern, thermally broken replacement.
- SE2
- SE9
- SE18
- SE28
- Guide from £1,095
Eltham: roof lantern replacement
In England, a rooflight on a house is usually permitted development if it projects no more than 150mm beyond the roof plane and is no higher than the highest part of the roof. Raised lanterns often stand taller than that, so check with the council before ordering.
Old polycarbonate or single glazed roof lanterns can be replaced with double glazed aluminium lanterns on the existing upstand, if the upstand is sound, level and the right size. Upstands that are rotten, uninsulated or out of level should be rebuilt first, which the survey identifies.
Opening skylights and lantern vents can be manual or electrically operated, often with a rain sensor that closes them automatically when it starts to rain. Electric vents need a power supply planned before plastering, so the wiring route is agreed at survey when an opening option is chosen.
Glass for lanterns usually comes with a self-cleaning outer coating that helps rain wash away dirt, and a choice of clear, neutral or blue-tinted solar-control glass. Solar-control glass limits heat build-up under a south-facing lantern, while clear low-E glass suits shaded or north-facing rooms.
What a typical job includes
- Removal and disposal of an old lantern or skylight
- Made-to-measure aluminium roof lantern or framed skylight
- Sealed double glazed units with laminated inner pane options
- Written guarantee terms and manufacturer documentation

Eltham at a glance
- Postcodes covered
- SE2, SE9, SE18, SE28 and the surrounding area, including Blackheath, Welling and Catford
- Coast
- Eltham is well inland, around 22 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Eltham 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 Eltham
| 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
Approved Document F covers ventilation. Replacing windows should not leave a room with worse background ventilation than before, which is why replacement windows often include trickle vents.
Options to choose between
Rectangular hipped lantern
A long ridge with hipped ends, suiting most rectangular extensions and kitchens, sized to the opening and the room below.
Square or octagonal lantern
A pyramid or eight-sided design that suits square rooms, orangeries and spaces where a central focal point is wanted.
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 Eltham: questions
Why does my roof lantern get condensation?
Condensation forms when warm, moist air from cooking, bathing or drying clothes meets the colder glass and frames at high level. Older single glazed or non thermally broken lanterns suffer most. Thermally broken frames, warm-edge spacers, extractor fans and opening vents reduce it. Some condensation on very cold mornings is normal and clears as the room warms.
How do I clean a roof lantern?
Self-cleaning coated glass lets rain lift most dirt, but a rinse with clean water in long dry spells helps. Clean from a safe position at the roof edge or from a suitable platform, never by standing on the lantern. Wipe the inside glass with mild soapy water, and keep leaves clear of the upstand and roof outlets.
Should the inner glass in a roof lantern be laminated?
Laminated inner glass is the safer choice and is recommended by the Rooflight Association. If a laminated pane breaks, the interlayer holds the pieces together, so glass is far less likely to fall into the room below. This matters most over kitchens, dining tables, stairs and seating, and it is offered as a standard option.
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.
Do you cover Eltham for roof lanterns?
Yes. We can quote for roof lanterns across Eltham and the surrounding Greater London area, including postcode districts SE2, SE9, SE18 and SE28, and nearby Blackheath, Welling and Catford. 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 Eltham
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.