Braintree · Essex
Roof Lanterns in Braintree
Is the middle of your extension in Braintree too dark? A roof lantern or skylight brings in light that wall windows cannot reach.
- CM7
- CM77
- Guide from £1,095
About roof lantern replacement in Braintree
A roof lantern is assembled from an aluminium ridge, hip bars and glazing bars that hold sealed glass units on each pitch. It sits on an upstand built around the roof opening. The upstand should be level, weathered into the roof covering and insulated, because a poor upstand causes most leaks and cold spots.
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.
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.
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.
What's included
- Written guarantee terms and manufacturer documentation
- Sealed double glazed units with laminated inner pane options
- Survey of the roof, opening, upstand and drainage
- Fixing, glazing and sealing onto the prepared upstand
Working in Braintree
- Postcodes covered
- CM7, CM77 and the surrounding area, including Witham, Chelmsford and Maldon
- Coast
- Braintree sits roughly 20 km from the nearest coastline, close enough that exposure on open or high ground is worth considering. Coastal lanterns face salt deposits on the glass and frames and strong uplift from wind on exposed roofs. Marine-grade coatings, stainless fixings and secure fixing to a well-built upstand matter, and salt film may need rinsing more often than self-cleaning glass manages alone.
- Daylight and sun
- In Braintree 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 Braintree
| 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.
Specification choices
Flat framed skylight
A low-profile framed rooflight on a flat roof upstand, fixed or opening, for bathrooms, landings and smaller rooms.
Rectangular hipped lantern
A long ridge with hipped ends, suiting most rectangular extensions and kitchens, sized to the opening and the room below.
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 Braintree: 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.
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.
Can I replace my old polycarbonate roof lantern with glass?
Yes, in most cases. A glass lantern is heavier than polycarbonate, so the upstand and roof structure must be able to carry it. If the upstand is sound, level and the right size, a new aluminium lantern can usually sit on it. If not, the upstand is rebuilt first, which the survey will identify.
Why does my roof lantern get condensation?
Condensation forms when warm, moist air from cooking, bathing or drying clothes meets the colder glass and frames at high level. Older single glazed or non thermally broken lanterns suffer most. Thermally broken frames, warm-edge spacers, extractor fans and opening vents reduce it. Some condensation on very cold mornings is normal and clears as the room warms.
Do you cover Braintree for roof lanterns?
Yes. We can quote for roof lanterns across Braintree and the surrounding Essex area, including postcode districts CM7 and CM77, and nearby Witham, Chelmsford and Maldon. 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 Braintree
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.