Johnstone · Renfrewshire & Inverclyde
Roof Lanterns in Johnstone
Old polycarbonate lanterns in Johnstone that leak, rattle or have yellowed can usually be replaced with a double glazed aluminium lantern on a sound upstand.
- PA5
- Guide from £1,095
Opening skylights in Johnstone: what to know
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.
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.
Warm, moist air rises and collects in a roof lantern, so condensation can form on cold winter mornings, especially over kitchens and bathrooms. Thermally broken frames, warm-edge spacers and good room ventilation reduce it, and opening vents in the lantern can release warm air in summer.
What a typical job includes
- Survey of the roof, opening, upstand and drainage
- Removal and disposal of an old lantern or skylight
- Fixing, glazing and sealing onto the prepared upstand
- Written guarantee terms and manufacturer documentation

Johnstone at a glance
- Postcodes covered
- PA5 and the surrounding area, including Paisley, Barrhead and Erskine
- Coast
- Johnstone sits roughly 12 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 Johnstone the midwinter sun reaches about 11° above the horizon at noon, with roughly 6.7 hours of daylight, rising to about 58° and 17.3 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 Scotland
- Section 4 (Safety) of the Scottish Technical Handbooks covers glazing that people could collide with, such as glass in and beside doors and low-level glazing, where safety glass is needed.
Guide prices in Johnstone
| 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
Glass in a fire-resisting door or screen must be replaced with fire-rated glazing tested as part of that system. Ordinary toughened glass is not a substitute.
Specification choices
Opening vents
Manual or electric vents in the lantern or skylight, with optional rain sensors that close them automatically in wet weather.
Rectangular hipped lantern
A long ridge with hipped ends, suiting most rectangular extensions and kitchens, sized to the opening and the room below.
Frame colours
Powder-coated aluminium in grey, black, white or other RAL colours, often dual colour to suit the roof and the room.
Roof Lanterns in Johnstone: questions
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.
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.
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.
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 you cover Johnstone for roof lanterns?
Yes. We can quote for roof lanterns across Johnstone and the surrounding Renfrewshire & Inverclyde area, including postcode districts PA5, and nearby Paisley, Barrhead and Erskine. 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 Johnstone
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.