Guide prices
Small sealed unit
Misted or cracked unit up to about 1 m² measured, made and refitted
Medium sealed unit
Units up to about 2 m², or toughened and laminated
Large or specialist
Triple glazed, solar-control or heavy units needing lifting gear
Guide ranges. The first visit is charged and priced before booking; any new glass 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.
Fitting across Harrow and nearby
If you also own a property or a business unit in Wealdstone, Brent or Wembley, that is no problem. We can survey and quote both, and where it suits, line the fitting days up together. Every address is reached by fitters travelling to it from their current jobs, and HA1, HA3 and HA2 sit comfortably within that pattern.
Included in the work
- Frame rebate cleaned and checked for damage, corrosion or failed seals
- Old glass taken out safely and removed from site
- Joints water tested and the glass cleaned inside and out
- Weight and lifting — We plan how a heavy pane gets onto the roof and into the frame.
- Condition of the frame — We look at the frame closely before committing to new glass.
How the glass is replaced
The second visit is the quick one. With the new unit made to size, the fitters take the old glass out, check the frame and drainage paths, and set the new glass on packers so it sits square and drains properly. Seals and cappings are renewed where needed, the area is cleared, and you are shown what was done.
Planning and building rules 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.
What to send us
To price the measuring visit, send a photo of the rooflight from inside showing the misting or crack, one from outside if you can reach a safe viewpoint, and the rough size of the glass. If you know the make or have the original paperwork, include that too, along with the postcode.
Common questions in Harrow
Is new glass or a new rooflight better value?
If the frame, gaskets and drainage are sound, new glass is usually the cheaper fix. If the frame is cracked, distorted or leaking at the kerb, a full replacement is better value. After the measuring visit we price both so you can compare.
How long does new rooflight glass take?
The new sealed unit is made to the measured size, so there is a gap between the measuring visit and the fitting visit while it is produced. We give you the expected timing when we price the glass, and book the fitting once it has arrived.
Can I upgrade the glass while it is being replaced?
Usually. Solar-control, self-cleaning, toughened or laminated glass can be specified as long as the frame can take the thickness and weight. We check that on the measuring visit and price the options side by side.
For a repair in Harrow, start with photos and the postcode; we confirm the visit price before anything is booked.

