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.
Areas around Cambridge we cover
If you also own a property or a business unit in Royston, St Ives or Newmarket, 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 CB2, CB4 and CB1 sit comfortably within that pattern.
Included in the work
- Measuring visit to size the glass and identify its make-up
- New unit set on packers, then beaded, capped or bonded as designed
- Sealed unit ordered to match or improve on the original glass
- Matching the glass make-up — We identify the existing glass so the replacement performs at least as well.
- Can the glass come out? — We check whether your rooflight has removable glass or a bonded unit before booking a fitting visit.
How the glass is replaced
On the fitting visit, the room below is protected first. The beads or cappings come off, the old unit is lifted out with suction lifters, and the rebate is cleaned and checked for damage or blocked drainage. The new sealed unit goes in on fresh packers and gaskets, the cappings are refitted and sealed, and the glass is cleaned. Most glass swaps take half a day once the new glass is made.
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
Photos of the problem glass from inside and out, a rough width and length, and whether the rooflight opens or is fixed are enough to price the first visit. Add the postcode and how the roof is reached, and tell us if more than one unit has misted.
Common questions in Cambridge
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.
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 you replace just the glass in my rooflight?
Often, yes. If the frame, gaskets and drainage are sound, a new sealed unit can go into the existing frame. If the frame has failed, is distorted or leaks around the edge, replacing the whole rooflight is usually the better answer, and we tell you that.
For a repair in Cambridge, start with photos and the postcode; we confirm the visit price before anything is booked.

