Harpenden · Hertfordshire
Roof Lanterns in Harpenden
A roof lantern in Harpenden can flood a dark extension or kitchen with daylight from above, and our glaziers check the roof and upstand before you receive a fixed written quote.
- AL5
- Guide from £1,095
Harpenden: roof lanterns
The price of a roof lantern or skylight depends on the size and shape, glass specification, frame colour, opening vents or electric operation, and whether the upstand already exists or needs building. Access to the roof and lifting large units add labour. See the guide prices for typical ranges.
In England, Approved Document L sets a limiting U-value of 2.2 W/m²K for rooflights, calculated in the horizontal position, for both new and existing homes. A kerb or upstand built on site should achieve 0.35 W/m²K or better. Ask for the lantern's declared horizontal U-value, not a vertical figure.
The Rooflight Association recommends laminated glass for the inner pane of glass rooflights, because laminated glass stays bonded together if it breaks instead of dropping fragments into the room below. Toughened inner panes are still used, but laminated is the safer choice over kitchens, stairs and seating areas.
Old polycarbonate or single glazed roof lanterns can be replaced with double glazed aluminium lanterns on the existing upstand, if the upstand is sound, level and the right size. Upstands that are rotten, uninsulated or out of level should be rebuilt first, which the survey identifies.
What you get
- Survey of the roof, opening, upstand and drainage
- Fixing, glazing and sealing onto the prepared upstand
- Removal and disposal of an old lantern or skylight
- Sealed double glazed units with laminated inner pane options
Working in Harpenden
- Postcodes covered
- AL5 and the surrounding area, including St Albans, Luton and Hemel Hempstead
- Coast
- Harpenden is well inland, around 64 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Harpenden the midwinter sun reaches about 15° above the horizon at noon, with roughly 7.5 hours of daylight, rising to about 62° and 16.5 hours in midsummer. Overhead glazing receives far more light than a wall window of the same size, especially when the sun is high in summer. South-facing lanterns may need solar-control glass, while low winter sun and north-facing rooms benefit from clear, high light-transmission low-E glass.
- Access and setting
- Rural roofs collect more leaves, moss and bird debris, so lanterns need clear upstand drainage and regular checks. Exposed sites see higher wind loads and driving rain, and older outbuildings may need the roof structure strengthening before a lantern is added.
- Rules in England
- Approved Document K requires safety glass in critical locations in England: glazing in doors and in side panels within 300 mm of a door, up to 1500 mm above floor level, and any glazing in walls or partitions up to 800 mm above floor level.
Guide prices in Harpenden
| Typical job | Guide price inc VAT |
|---|---|
| Lantern 1500 × 1000 mm, fitted to a kerb | £1,395 – £1,795 |
| Lantern 2000 × 1000 mm | £1,695 – £2,095 |
| Lantern 3000 × 1500 mm | £2,795 – £3,695 |
| Flat glass rooflight 1000 × 1000 mm | £1,095 – £1,395 |
Get a guide price for your size
In England, replacing a whole window, roof window or glazed external door is building work. It has to be notified to building control, either by an installer registered with a competent person scheme such as FENSA or Certass, or through a building notice to the council. Replacing only the glass in an existing frame is a repair and is not notifiable.
Options to choose between
Rectangular hipped lantern
A long ridge with hipped ends, suiting most rectangular extensions and kitchens, sized to the opening and the room below.
Square or octagonal lantern
A pyramid or eight-sided design that suits square rooms, orangeries and spaces where a central focal point is wanted.
Opening vents
Manual or electric vents in the lantern or skylight, with optional rain sensors that close them automatically in wet weather.
Roof Lanterns in Harpenden: questions
Does fitting a roof lantern need building regulations approval?
A new roof lantern or skylight generally needs building regulations approval, because the roof structure is cut and must be supported, and the unit must meet energy standards. Fire performance also matters near a boundary. Replacing a lantern on an existing sound upstand is simpler, and we explain which route applies at survey.
How long does it take to fit a roof lantern?
Fitting a roof lantern on a prepared upstand usually takes a day or less for a typical size, longer for large or complex shapes. The lantern is made to order first, and the lead time depends on its size, shape and colour. Building or rebuilding an upstand is separate roofing work that comes before fitting.
What guarantee comes with a roof lantern?
Manufacturer guarantees apply to the frame, coating and sealed units, and the terms are confirmed in writing. The upstand and roof covering may be covered separately, depending on who builds them. Guarantee terms for the installation are set out in writing with your quote, so you know exactly what is covered before going ahead.
Should the inner glass in a roof lantern be laminated?
Laminated inner glass is the safer choice and is recommended by the Rooflight Association. If a laminated pane breaks, the interlayer holds the pieces together, so glass is far less likely to fall into the room below. This matters most over kitchens, dining tables, stairs and seating, and it is offered as a standard option.
Do you cover Harpenden for roof lanterns?
Yes. We can quote for roof lanterns across Harpenden and the surrounding Hertfordshire area, including postcode districts AL5, and nearby St Albans, Luton and Hemel Hempstead. Start with your postcode on the quote form and a glazier will arrange a free survey before giving you a written quote.
Get a written quote in Harpenden
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.