Guide prices in Hertfordshire
Diagnostic visit
Roof and inside inspected, cause found, written repair price
Reseal and re-flash
Failed sealant and flashing taken out, joints cleaned, resealed and taped
Upstand or membrane repair
Rotten kerb section or roof membrane at the upstand repaired
Guide ranges. The first visit is charged and priced before booking; any repair is priced in writing before work starts. Scaffold, access towers or a crane are priced separately if the job needs them, and building control fees, where a job needs them, are shown as their own line.
Towns we list in Hertfordshire
Coverage in Hertfordshire works by postcode, not by distance from an office. Give us the full postcode and we will confirm whether it is standard cover, as it is for most of England, or one of the few remote and island areas handled by arrangement. Either way, you get a written quote before any work is booked, with travel included in the price.
- Leak repairs in Berkhamsted
- Leak repairs in Bishops Stortford
- Leak repairs in Borehamwood
- Leak repairs in Bushey
- Leak repairs in Cheshunt
- Leak repairs in Harpenden
- Leak repairs in Hatfield
- Leak repairs in Hemel Hempstead
- Leak repairs in Hertford
- Leak repairs in Hitchin
- Leak repairs in Hoddesdon
- Leak repairs in Letchworth Garden City
- Leak repairs in Potters Bar
- Leak repairs in Rickmansworth
- Leak repairs in St Albans
- Leak repairs in Stevenage
- Leak repairs in Ware
- Leak repairs in Watford
- Leak repairs in Welwyn Garden City
What's included
- Failed sealant cut out, joints cleaned, dried and resealed
- Lifted flashing or tape removed and renewed
- Outside inspection of glass, frame, sealant, flashing and roof covering
- Upstand height and condition — We measure the kerb and probe the timber for softness.
- Leak or condensation — We work out whether the water is coming from outside or forming inside on cold glass.
Rules that apply in England
In England, a new rooflight opening generally needs building regulations approval because the roof structure is altered and the glazing must meet energy rules: 2.2 W/m²K for a rooflight in an existing home, or 1.4 W/m²K (or WER Band B) for a roof window. Planning is often not needed on a house: permitted development covers rooflights that stand no more than 0.15 m proud of the roof slope and sit below the highest part of the roof. Flats, listed buildings and areas with an Article 4 direction are different, so we check your address first.
Common questions in Hertfordshire
Will resealing fix my leaking rooflight?
Sometimes. If the sealant has simply aged and the flashing, upstand and glass are sound, a careful reseal on a dry day can solve it. If the real problem is ponding water, a low upstand or a perished membrane, fresh sealant will only hide it for a while. We tell you which one you are dealing with before recommending any work, and quote the proper fix in writing.
Can you replace just the misted glass?
Often, yes. Misting between the panes means the sealed unit has failed, but the frame around it may be perfectly sound. Where the maker's design allows the glass to be changed, we measure the unit and fit a replacement, which costs less than a whole new rooflight. Where it does not, or the frame is also worn out, we explain why replacement is the better option.
Is it condensation or a leak?
Condensation tends to appear on cold mornings, on the inner face of the glass, and runs down the frame. A leak usually follows rain or wind from a particular direction and often stains the ceiling around the opening. Blocked condensation channels can make the two look alike. Photos and a note of when it happens help us narrow it down before the visit.

