Sleaford · Lincolnshire
Roof Lanterns in Sleaford
If your skylight in Sleaford drips with condensation or leaks around the frame, we can survey it and quote for a modern, thermally broken replacement.
- NG34
- Guide from £1,095
Opening skylights across Sleaford
Cutting a new opening for a roof lantern or skylight usually means trimming joists or rafters, so the roof can carry the load around the hole. Building regulations approval is generally needed for a new rooflight, covering structure, energy performance and, near a boundary, fire performance.
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.
Roof lanterns are not designed to be walked on, so never stand or lean on the glass or bars. Cleaning and inspection should be done from safe access at the edge of the roof. Keep leaves and debris away from the upstand and roof outlets so water drains freely.
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's included
- Removal and disposal of an old lantern or skylight
- Survey of the roof, opening, upstand and drainage
- Made-to-measure aluminium roof lantern or framed skylight
- Fixing, glazing and sealing onto the prepared upstand
About Sleaford for this job
- Postcodes covered
- NG34 and the surrounding area, including Grantham, Boston and Lincoln
- Coast
- Sleaford is well inland, around 30 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Sleaford the midwinter sun reaches about 14° above the horizon at noon, with roughly 7.3 hours of daylight, rising to about 60° and 16.7 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 Sleaford
| 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
Approved Document F covers ventilation. Replacing windows should not leave a room with worse background ventilation than before, which is why replacement windows often include trickle vents.
Options to choose between
Square or octagonal lantern
A pyramid or eight-sided design that suits square rooms, orangeries and spaces where a central focal point is wanted.
Solar-control glass
Neutral or blue-tinted coatings that reduce heat build-up under south or west-facing lanterns while keeping daylight levels high.
Flat framed skylight
A low-profile framed rooflight on a flat roof upstand, fixed or opening, for bathrooms, landings and smaller rooms.
Roof Lanterns in Sleaford: questions
Will a roof lantern make my room too hot?
A roof lantern can add heat on sunny days, especially facing south or west, because overhead glass receives sun for much of the day. Solar-control glass, opening vents and blinds help keep the room comfortable. The glass is chosen at survey based on the lantern's size and orientation and how the room is used.
Do I need planning permission for a roof lantern?
Sometimes. In England, rooflights on a house are usually permitted development if they project no more than 150mm above the roof plane and are no higher than the highest part of the roof. Raised lanterns often exceed that, and flats, listed buildings and conservation areas have extra controls, so check with your council first.
How much does a roof lantern cost?
The cost of a roof lantern depends on its size and shape, the glass specification, frame colour, any opening vents, and whether the upstand exists or needs building. Access to the roof and lifting a large lantern also affect labour. See the guide prices for typical ranges; the written quote fixes the price for your exact specification.
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 Sleaford for roof lanterns?
Yes. We can quote for roof lanterns across Sleaford and the surrounding Lincolnshire area, including postcode districts NG34, and nearby Grantham, Boston and Lincoln. 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 Sleaford
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.