How much do French doors cost in the UK?

In 2026, uPVC French doors typically cost £1,000-£1,500 supply and install. Hardwood timber French doors range from £1,800-£2,800. Aluminium options cost £1,500-£2,200. Adding sidelights increases costs by 35-65%. Bay/bow configurations are significantly more.

What is the standard size for French doors?

The most common French door opening is 1800mm wide by 2100mm high, giving two 900mm-wide door leaves. Openings can range from 1200mm (narrow pair) to 2400mm with sidelights. The maximum practical leaf width is about 900mm before the door becomes too heavy for hinges.

Do French doors need to comply with Building Regulations?

Yes, replacement French doors must meet Part L thermal requirements with a maximum U-value of 1.4 W/m²K (or equivalent). They must also meet Part N safety glazing requirements and Part Q security standards (PAS 24:2016). The installer should be FENSA or CERTASS registered.

Are French doors secure?

Modern French doors meeting PAS 24:2016 are very secure, with multi-point locking mechanisms, reinforced frames and toughened or laminated glass. Look for Secured by Design accreditation for enhanced security. The slave door should have robust shoot bolts top and bottom.

French doors vs bi-fold doors - which is better?

French doors are more affordable, provide a classic look and offer good ventilation. Bi-fold doors create a wider opening (up to 6m+) and fold neatly to one side, but cost 2-3 times more. French doors suit standard openings; bi-folds suit wider spans where you want to open up an entire wall.

TradeCalculator.co.uk

French Door Calculator

Estimate the cost of French doors in uPVC, timber, aluminium or composite with sidelights. Check Part L U-value compliance for UK installations.

Frame MaterialuPVC is the most affordable option

ConfigurationSidelights widen the opening

GlazingDouble glazed is standard

Opening Width

Structural opening width

Opening Height

Structural opening height

Base Price

Base supply and install cost

How We Calculate This

This calculator estimates French door costs based on material, configuration, glazing specification and optional extras.

The formula

Total = Base price × Material factor × Config factor × Glazing factor + Extras

Material: uPVC (1.0x), aluminium (1.5x), timber (1.8x), composite (2.0x)
Config: pair only (1.0x), +1 sidelight (1.35x), +2 sidelights (1.65x)
Triple glazing adds approximately 20% to cost

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.