Guide prices in Harpenden
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 Harpenden and nearby
Our fitters come to you. For Harpenden that covers AL5, AL3 and AL4, plus nearby St Albans and Luton. 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 the job includes
- Insulation fitted to the upstand faces to limit heat loss
- Kerb sized from the maker's drawing, internal and external dimensions both checked
- Roof membrane turned up, bonded and finished at the kerb top
- 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.
- Size tolerance on the kerb — We build kerbs to a tight tolerance because rooflight glass is made to order and cannot be trimmed on site.
A typical installation day
Building an upstand starts with the rooflight's own drawing: its kerb size, height above the finished roof and fall. The team sets the timber out to those figures, checks the diagonals, insulates the outer faces and dresses the membrane up and over. If the rooflight is going on the same day, it is fitted next; if not, the kerb is protected until it does.
Do you need permission in Harpenden?
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
What we cannot see, we have to guess, and guesses make quotes wider. So the more you send, the tighter the price. Useful: shots from the roof or garden, shots from the room underneath, a rough width and length, the roof finish, any access problems, and the product page if you have already ordered. Add the property postcode around AL5 and we will come back with a quote or a survey date.
Common questions in Harpenden
Does a rooflight need building regulations approval?
A new opening usually needs building regulations approval. A replacement is a controlled fitting: it must be self-certified by an installer registered with a competent person scheme or notified to building control. We are not registered with a scheme, so replacements we fit are notified to building control with a building notice, and the council's fee is shown on your quote.
Do I need planning permission for a rooflight in Harpenden?
Often not. Many rooflights fall under permitted development, provided they do not project beyond the national limit and meet the other conditions that apply in England. Conservation areas, listed buildings and some flats are different and may need consent. Because the rules depend on the property, we confirm what is likely to apply at your address and point you to the planning authority where an application is needed.
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.
Send a few photos and your AL5 postcode, and we will put together a written quote for the job.

