Portishead · Somerset
Aluminium Windows in Portishead
Aluminium windows in Portishead give slimmer frames and more glass than most alternatives, and our glaziers survey every opening before you receive a fixed written quote.
- BS20
- Guide from £925
Replacement aluminium windows in Portishead: what to know
Aluminium is strong enough to hold large, heavy glass units in narrow frames, so sightlines are slimmer than uPVC of the same size. That means more glass and more daylight from the same opening, which suits modern extensions, wide picture windows and slim replacements for old steel windows.
Modern aluminium window frames contain a thermal break: strips of low-conductivity material, usually polyamide, that separate the inner and outer aluminium. Without it, heat passes straight through the metal. Older aluminium windows made without thermal breaks are a common cause of cold frames and streaming condensation.
In England, a replacement window in an existing home should achieve a U-value of 1.4 W/m²K or better, or a Window Energy Rating of band B, under Approved Document L. Thermally broken aluminium with low-E double glazing can meet this; ask for the certified whole-window figure, not just the glass value.
Large aluminium windows that reach low down, such as floor-to-ceiling glazing, need safety glass. In England, Approved Document K treats glazing within 800mm of the floor as a critical location, so those panes are usually toughened or laminated and permanently marked to show their safety classification.
What a typical job includes
- Thermally broken aluminium frames powder coated to order
- Removal and disposal of the existing windows
- Written guarantee terms and advice on building regulations sign-off
- Survey, measuring and structural check of each opening

Local details for Portishead
- Postcodes covered
- BS20 and the surrounding area, including Nailsea, Clevedon and Caldicot
- Coast
- Portishead is about 2 km from the coast or a tidal estuary, so salt air and wind-driven rain are worth planning for. Salt air attacks metal finishes, so aluminium windows near the coast need a coating and pretreatment suited to marine exposure, stainless or protected hardware, and more frequent washing. Check that the coating terms allow for a coastal site before ordering.
- Daylight and sun
- In Portishead the midwinter sun reaches about 15° above the horizon at noon, with roughly 7.6 hours of daylight, rising to about 62° and 16.4 hours in midsummer. Slim aluminium frames let more daylight through the same opening. Large south or west-facing panes can overheat rooms, so solar-control glass may help, while north-facing rooms benefit from high light-transmission low-E glass that keeps heat in during short winter days.
- Access and setting
- Rural homes often mix old stone walls with modern extensions, and aluminium suits both when profiles are chosen carefully. Irregular openings are measured individually, and exposed sites benefit from systems with high weather ratings and well-sealed joints against driving rain.
- 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 Portishead
| Typical job | Guide price inc VAT |
|---|---|
| Casement window, 900 × 1050 mm | £925 – £1,195 |
| Casement window, 1200 × 1200 mm | £1,095 – £1,395 |
| Large window, 1800 × 1500 mm | £1,495 – £1,995 |
| Slimline heritage style, 1200 × 1200 mm | £1,295 – £1,695 |
Get a guide price for your size
Approved Document Q applies to new homes in England, where doors and windows are expected to meet PAS 24 or an equivalent standard. It does not apply to replacements in existing homes, but PAS 24 products are still a sensible choice.
Options to choose between
Casement windows
Side-hung, top-hung or fixed sashes in slim aluminium frames, suiting most houses and extensions, with flush or stepped sash designs.
Steel-look windows
Very slim frames with glazing bars that mimic traditional metal windows, adding thermal performance and double glazing to the classic look.
Glass upgrades
Triple glazing, laminated acoustic glass, solar-control coatings or obscure glass, chosen per window to suit the room and elevation.
Aluminium Windows in Portishead: questions
How long does it take to install aluminium windows?
Most single windows are fitted within a day, and a typical house takes a few days on site depending on the number of windows and the access. The longer part is manufacturing, because frames are cut, coated and glazed to the survey sizes. The expected lead time is confirmed in writing when you accept the quote.
Do I need permission to replace windows with aluminium?
In England, replacing windows on a house with ones of similar appearance usually does not need planning permission, but changing the material or style can matter. Flats and maisonettes lack permitted development rights for windows, and listed buildings, conservation areas and Article 4 directions can require consent. Building regulations apply to replacement windows across the UK, with different detail in each nation.
Are aluminium windows secure?
Aluminium windows can be very secure, because the metal is strong and the frames carry multi-point locks, internal glazing beads and lockable handles. For easily accessible windows in new homes in England, Approved Document Q expects PAS 24 security. Asking for windows tested to that standard is a good benchmark when replacing ground-floor windows in an existing home.
Can aluminium windows replace original steel windows?
Yes, steel-look aluminium windows are designed for this. They copy the slim frames and glazing bars of old metal windows while adding double glazing and a thermal break. Original steel frames are often set into the masonry, so removal can disturb render or plaster, and the survey checks this. Listed buildings and conservation areas may need consent first.
Do you cover Portishead for aluminium windows?
Yes. We can quote for aluminium windows across Portishead and the surrounding Somerset area, including postcode districts BS20, and nearby Nailsea, Clevedon and Caldicot. Start with your postcode on the quote form and a glazier will arrange a free survey before giving you a written quote.
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