Aluminium French doors are double outward or inward-opening doors with slim metal frames and large glass panels. In the UK they now outsell wooden French doors by 3:1 (2024 Glass & Glazing Federation data) because they last 40+ years, need almost no maintenance and let in up to 25% more natural light than uPVC or timber equivalents.
This guide gives you exact specs, real 2025 prices, common pitfalls and proven fixes based on 12+ years installing and supplying these doors across the UK.
The 5 Biggest Problems Aluminium French Doors Actually Solve
- Not enough daylight in typical UK homes Slim sightlines of 28–35mm mean up to 90% of the door is glass. A standard 1800mm wide pair gives 3.78 m² of clear glass – 0.8 m² more than the same size in uPVC.
- High energy bills and cold spots near patio doors Thermal-break polyamide strips and triple glazing drop U-values to 1.0–1.2 W/m²K. Independent tests show a 22–28% reduction in heat loss compared to old timber doors.
- Wood rot and constant repainting in wet or coastal areas Marine-grade powder coating and 6063-T6 alloy withstand salt spray and driving rain. Zero rot recorded in 10-year coastal exposure trials.
- Weak security on rear patio doors PAS 24:2016 certified models use 8–10 point locking, anti-lift pins and toughened or laminated glass. Insurance-approved and police Secured by Design listed.
- Trip hazards and wheelchair access issues Part M low thresholds (13–15mm rise) or fully flush weathered sills solve the step problem that standard 50–70mm timber thresholds create.
Key Technical Features You Need to Know
- Frame depth: 70–90mm for strength and triple glazing pocket
- Max single panel weight supported: 200 kg (allows 3000mm tall doors)
- Glass options: Double 1.2 U-value | Triple 0.8–1.0 U-value | Solar control or acoustic laminates
- Colours: Any RAL code, dual colour (white inside/grey outside) at no extra cost from most UK factories
- Opening direction: Outward for patios (saves indoor space) | Inward for Juliet balconies or room dividers
2025 Real UK Prices (Supply Only + Supply & Fit)
| Size (mm) | Finish | Glazing | Supply Only | Supply & Fit |
|---|---|---|---|---|
| 1200 × 2100 | White | Double | £1,180–£1,450 | £1,950–£2,400 |
| 1800 × 2100 | Anthracite | Triple | £1,950–£2,450 | £2,850–£3,600 |
| 2400 × 2100 | Black matt | Triple + blinds | £3,200–£3,800 | £4,300–£5,200 |
Add £200–£350 for dual colour, £150–£250 for integral blinds.
Buyer’s Checklist – Avoid the Most Common (and Expensive) Mistakes
- Measure the structural opening, not the old door. Allow 10mm tolerance all round.
- Check brickwork is plumb – older houses often lean 10–15mm over height.
- Decide outward or inward before ordering – you cannot change it later.
- Insist on PAS 24 and BFRC certificates – cheap imports rarely have them.
- Order low threshold if anyone uses a wheelchair or pushchair.
- Get the survey done by the factory, not just the salesman.
Installation Reality – What Actually Happens on the Day
Professional fit takes 4–6 hours for a standard pair.
- Old frame removed, new packers and shims level the opening, door hung and aligned to within 1mm, expanding foam and silicone seal, handles and locks adjusted. Most common DIY mistake: over-tightening hinge bolts → frame twists → doors rub after 6 months.
Maintenance for 30+ Years of Zero Hassle
- Wash frames twice a year with warm soapy water
- Spray hinge pins and locks with PTFE lubricant once a year
- Check door seals for cracks every 5 years – £120 to replace the full set That’s it. No sanding, no painting, no varnishing.
Real UK Examples
- Brighton seafront flat – swapped 30-year-old softwood for marine-grade grey aluminium in 2023. Zero corrosion after two winters of salt spray.
- Manchester new-build extension – 2400mm triple-glazed black pair achieved full Passivhaus airtightness on blower-door test.
- 1930s semi in Bristol – inward-opening cream doors with monkey-tail handles kept the heritage look while adding modern security.
For full technical details see the Wikipedia page on French doors.
Ready to replace leaky, draughty or rotten patio doors with something that actually lasts? Drop your rough sizes in the comments or DM and I’ll send you current lead times and exact quotes from three trusted UK manufacturers – no sales pressure, just straight numbers.
