In Chiswick, as everywhere, resealing is the planned, whole-lantern version of a leak repair: we cut out the old, failed sealant, clean every joint back to a sound surface and reseal the cappings, ridge and eaves with materials that suit the frame. Send photos and we'll tell you what we think has failed.

Signs you need roof lantern resealing
- Cracked, split or shrunken sealant along the bars
- Several small leaks rather than one obvious one
- Sealant applied over sealant from previous patch repairs
Why it happens
Wrong product used
General-purpose or acetoxy silicone can fail early on some frames and coatings. Glazing joints need a low-modulus, compatible sealant.
Patch over patch
Fresh sealant run over old, dirty sealant rarely bonds. It looks fixed for a season and then lets go.
Roof lanterns in Chiswick
Drier, sunnier parts of the UK are kinder to seals than the wet west, but strong sun ages sealant, gaskets and plastic end caps, and south- or west-facing lanterns can make rooms very warm. Solar control glass and an opening vent help.
Across London, many lanterns sit on rear extensions with access only through the house, so we protect floors and plan the work to keep time indoors to a minimum. Parking and any permits are factored into the quote.
Chiswick is around 5 miles from Westminster, and both are within our Greater London coverage.
If you're just outside Chiswick, we also cover Acton (1 mile), Barnes (1 mile), Shepherds Bush (2 miles).
What should you expect to pay in Chiswick?
Typical range: £245–£495 ex VAT, which is £294–£594 with VAT, per lantern. Towers or scaffold, where needed, are priced into the quote. Your fixed price is confirmed in writing before any work starts.
Do you need permission in England?
Straightforward repairs — resealing, gaskets, cappings, eaves and like-for-like parts — don't normally need building regulations approval in England. Replacing the whole lantern or enlarging the opening is different and falls under the Building Regulations 2010; we confirm in writing which route applies before any replacement. Listed buildings need listed building consent from the local council for alterations, and conservation areas can have extra controls; like-for-like repairs are treated differently from changes, so check with the council's conservation officer first.
How does it work?
- Send photosWhatsApp or upload a few photos and tell us when it leaks.
- Guide priceWe reply with a guide price and whether a visit is needed.
- Fixed price in writingYou approve the price and the date before anything starts.
- Repair and testWe fix what's failed, water-test where it matters, and send photos.
Roof lantern resealing in Chiswick: questions
Can you repair a lantern someone else installed in Chiswick?
Yes. We repair lanterns whoever fitted them. If yours is still under the installer's warranty, contact them first so you don't affect it.
Which places near Chiswick do you cover?
As well as Chiswick, we cover nearby Acton, Barnes, Shepherds Bush, Notting Hill and the rest of Greater London.
How much does it cost to reseal a roof lantern?
A standard-size lantern on a single-storey extension is usually £245–£495 ex VAT. Larger lanterns, difficult access or gasket replacement add to that, and you get the fixed price in writing first.
How long does resealing take?
Most domestic lanterns take a few hours in dry weather.
Other lantern repairs in Chiswick
- Eaves beam and gutter repairs in Chiswick
- Upstand and kerb repairs in Chiswick
- Flat roof junction and flashing repairs in Chiswick
- Leak investigation and inspection in Chiswick
- Cleaning and maintenance in Chiswick
- Urgent leak make-safe in Chiswick
Roof lantern resealing near Chiswick
More about roof lantern resealing · All roof lantern repairs in Chiswick