What the job costs in Cardiff
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.
Coverage in and around Cardiff
Jobs across CF10, CF11 and CF24 are part of our normal cover for Cardiff. We are not an office on the high street. Our fitting teams come out to the property from wherever they are working that week. Neighbouring places such as Penarth and Caerphilly are covered on the same terms, so a house on the edge of town is no harder to book than one in the centre.
On the day, we cover
- Sealed unit ordered to match or improve on the original glass
- New unit set on packers, then beaded, capped or bonded as designed
- Measuring visit to size the glass and identify its make-up
- Condensation or a failed seal — We confirm whether the mist is inside the sealed unit or on the room-side surface.
- Matching the glass make-up — We identify the existing glass so the replacement performs at least as well.
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.
Regulations for Cardiff properties
Welsh rules differ from England's in one important way: rooflights lose permitted development rights in conservation areas, National Parks, AONBs and World Heritage Sites. Elsewhere on a house, a rooflight that projects no more than 150 mm and stays below the highest part of the roof is usually fine. Building regulations still apply to new openings, replacements we fit go through a building notice because we are not scheme-registered, and the energy limit for rooflights is 2.2 W/m²K. A new Welsh Approved Document L takes effect on 4 March 2027.
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 Cardiff
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.
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.
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.
Got a leak or a misted unit in Cardiff? Send photos first and we will tell you what the visit costs before booking.

