What the job costs in Welwyn Garden City
Timber upstand
Treated timber kerb built square and level to the maker's size
Insulated upstand
Kerb with insulation and the roof membrane turned up and dressed
Large or with trimming
Bigger kerbs or where joists need trimming first
Guide ranges for labour and materials, rooflight not included. Your price is fixed in a written quote after we have seen photos or surveyed. 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 Welwyn Garden City and nearby
Our fitters come to you. For Welwyn Garden City that covers AL8, AL7 and AL6, plus nearby Hatfield and Hertford. We do not keep a yard or showroom in the area, and you do not need to visit one. The survey happens at your property or, for fit-only work, from the photos you send. Dates follow fitter availability, which we confirm when you accept the quote.
What we do on the day
- Kerb sized from the maker's drawing, internal and external dimensions both checked
- Height set above the finished roof to the maker's stated minimum
- Insulation fitted to the upstand faces to limit heat loss
- Energy limit for site-built kerbs — We insulate upstands to meet the limit for site-built upstands, which is 0.35 W/m²K in England and Wales.
- Roof covering compatibility — We check what the roof is covered in before choosing how the membrane meets the kerb.
From arrival to clean-up
The fitters measure twice before cutting: the opening, the rooflight's kerb size and the finished roof level. The kerb is built, packed level or to the maker's fall, insulated and weathered into the roof covering. You are left with an upstand ready for the rooflight, and a note of the sizes it was built to.
Planning, building control and Welwyn Garden City
Replacing a rooflight in an English home is a controlled fitting: it has to be self-certified by a scheme-registered installer or notified to building control. We are not registered with a competent person scheme, so replacements we fit are notified with a building notice, and the new unit has to meet current energy limits. Adding a new one usually means a building regulations application, because joists or rafters are trimmed. On the planning side, most house rooflights are permitted development if they project 0.15 m or less; on a side slope the glass must be obscured and fixed unless the opening part is over 1.7 m above the floor.
Getting a price from photos
Each detail you send takes a question off our list. Photos inside and out show the opening and the ceiling. Rough measurements tell us the unit size. The roof covering tells us how it will be sealed in. Access notes tell us whether a tower or scaffold is needed. A product link, if you have one, lets us check it against the opening. Your postcode, AL8 or nearby, confirms travel.
Common questions in Welwyn Garden City
Do you make good inside after fitting?
Yes, where the quote includes it. Internal finishing usually means lining the reveal with plasterboard, taping or skimming, and fitting trim where it meets the ceiling. Some people prefer their own plasterer or decorator to finish off, which is fine. The written quote spells out exactly where our work stops, so nobody is left guessing about who does what once the unit is in.
Do you need scaffolding to fit a rooflight?
Not always. Single-storey roofs can often be reached safely with ladders, a tower or edge protection. Higher roofs, steep pitches and large units usually need scaffold or a mobile platform, and heavy glass may need a crane. We assess access from your photos or at the survey, and any scaffold or lifting cost is shown as its own line on the written quote.
Do you offer trade rates for builders and roofers?
We carry out subcontract fitting for builders, roofers, extension companies and commercial contractors. Pricing is per job or per schedule of units, agreed in writing before we start. We can work to your programme, fit on your upstand or build our own, and leave the opening ready for the next trade. Send drawings or a unit schedule and we will come back with a trade quote.
Send a few photos and your AL8 postcode, and we will put together a written quote for the job.

