French Doors vs Patio Doors: Which Is Cheaper? (2026 UK Guide)

Quick Answer: French Doors or Patio Doors, Which Should You Choose?

French doors, a pair of hinged doors opening outward or inward from the centre, suit properties with garden space where the full opening can be used and give a classic, symmetrical appearance. Sliding patio doors, moving horizontally along a track, save floor space since they do not swing open, making them a better fit for smaller gardens, balconies, or rooms where furniture placement limits door swing.

French Doors: Features and Considerations

Opening style: Hinged pair, typically opening outward, sometimes inward
Cost: £800 to £2,500 depending on frame material and glazing specification
Best for: Properties with garden space to accommodate outward opening, period and traditional style homes
Considerations: Needs clear space to open fully, both doors typically need to be open for a full width opening

Sliding Patio Doors: Features and Considerations

Opening style: Horizontal sliding along a track, no outward swing
Cost: £700 to £3,000 depending on size, panel configuration, and frame material
Best for: Smaller gardens or balconies, rooms where furniture limits door swing space, contemporary properties
Considerations: Track needs regular cleaning to maintain smooth operation, only half the opening is typically usable at once with a standard two panel slider

Aluminium Patio Doors

Aluminium patio doors have become increasingly popular for their slim sightlines, allowing more glass and less visible frame than uPVC equivalents, along with excellent durability and a contemporary appearance that suits modern extensions particularly well.

Bi-Fold Doors as a Third Option

Bi-fold doors, folding back in a concertina action similar to internal bifold doors but designed for external use, offer the widest possible fully open aperture of the three main options, making them popular for kitchen extensions wanting to fully connect indoor and outdoor space during warmer weather.

French vs Sliding vs Bi-Fold Doors Comparison

Feature	French Doors	Sliding Patio Doors	Bi-Fold Doors
Floor space needed to open	Yes, outward swing	No	Minimal, folds against frame
Maximum open aperture	Full width if both doors open	Half the total width typically	Nearly full width
Cost range	£800 to £2,500	£700 to £3,000	£1,500 to £5,000+
Best for	Period properties, gardens	Small spaces, balconies	Kitchen extensions, full opening

Are French Doors Cheaper Than Patio Doors? Cost by Opening Size

Asking which door is cheaper misses the key factor: the width of your opening. Neither door type wins on price in every situation. What changes the answer is how wide the aperture is, because each door type has a natural size range where it represents the best value.

For a standard doorway of 1.2 to 1.8 metres, uPVC French doors are usually the cheapest option. Installed prices typically start from around £750, compared with around £850 for a uPVC sliding patio door. At these widths the two average around £900 installed for a like-for-like replacement, so the gap is modest, but French doors hold the edge.

The picture changes above about 1.8 metres. French door sets are rarely manufactured wider than this, so filling a wider opening with the classic look means adding sidelights, the fixed glass panels fitted either side of the doors. Each sidelight typically adds £200 to £500, and two of them can erase the saving that made French doors cheaper in the first place.

Sliding patio doors scale far more naturally to wider openings, with two, three, and four panel configurations available up to about 4 metres. For a 2.4 or 3 metre opening, a sliding set often works out cheaper overall than French doors plus sidelights, and it gives you the uninterrupted glass that suits a wide aperture better. A useful rule of thumb: under 2 metres, French doors win on price; from 2 to 3.5 metres, sliding patio doors usually balance cost and function best; above 3.5 metres, bi-fold doors become the practical choice.

Opening width	Cheapest option typically	Indicative installed range, uPVC, 2026
1.2 to 1.8m	French doors	£750 to £1,200
1.8 to 2.4m	Either; compare sidelights against a slider	£850 to £1,800
2.4 to 3.5m	Sliding patio doors	£1,200 to £2,500
Above 3.5m	Bi-fold doors	£2,500 upwards

Material moves these figures a lot. Aluminium typically adds 30 to 50 percent to a uPVC equivalent, while timber usually costs more still and needs repainting or resealing every 3 to 5 years. Prices include VAT at 20 percent, and London and the South East usually quote 15 to 20 percent more than the North. Get at least three written quotes from FENSA registered installers on a like-for-like specification, because quotes can vary by 30 to 50 percent for the same doors.

Glass Sliding Doors: Internal Uses

Glass sliding doors are also used internally to divide open plan spaces without permanently closing them off, offering a similar space saving benefit to external sliding patio doors while allowing light to pass between rooms when closed.

Security Considerations for French and Patio Doors

Given their large glazed area, French and patio doors are sometimes considered a security weak point compared to a solid front door. Multi point locking systems, laminated security glass, and reinforced frames all help address this, and checking these specifications is worth prioritising over appearance alone when comparing quotes.

Maintaining Sliding Patio Doors

Clean the track regularly to remove dirt and debris that can cause the door to stick or run unevenly
Lubricate rollers periodically with a suitable silicone based lubricant
Check and adjust the door alignment if it becomes difficult to slide smoothly
Inspect weather seals annually for wear that could let in draughts

Are French doors cheaper than patio doors?

Yes, French doors are usually cheaper at standard opening widths up to 1.8 metres, with installed prices starting from around £750 in uPVC compared with around £850 for a sliding patio door. The saving shrinks on wider openings where French doors need sidelights to fill the gap.

Why do French doors cost more above 1.8 metres wide?

Most French door sets are manufactured no wider than about 1.8 metres, so wider openings need fixed glass sidelights on each side. Each sidelight typically adds £200 to £500, which can push the total above the cost of a sliding patio door for the same opening.

What is the cheapest patio door material?

uPVC is the cheapest frame material for both French and sliding patio doors, with like-for-like sets typically averaging around £900 installed. Aluminium adds roughly 30 to 50 percent and suits wider openings with slimmer sightlines, while timber costs more and needs regular resealing.

How much extra does a new patio door opening cost?

Creating a new opening in an external wall typically costs £1,900 to £3,500 in total including the steel lintel. This is often more than the doors themselves, so replacing doors in an existing opening is far cheaper than widening or creating one.

Do patio doors need to be fitted by a FENSA registered installer?

Not legally, but a FENSA registered installer self-certifies the work to Building Regulations and registers it with the local authority. Fitting by an unregistered installer or doing it yourself means applying to building control separately, which typically costs £200 to £500.

Frequently Asked Questions

Are French doors or sliding doors more energy efficient?

Both can achieve similar thermal performance when specified with good quality glazing and frames, so energy efficiency depends more on glazing specification than the opening mechanism itself.

Do sliding patio doors let in more light than French doors?

Sliding patio doors and French doors can both be specified with similarly large glazed areas, so light transmission depends more on the specific panel design and frame width than the opening style itself.

Can you fit French doors into an existing patio door opening?

In many cases yes, though the exact fit depends on the opening dimensions, and some adjustment to the surrounding structure may be needed if the opening does not match standard French door sizing.

Which is more secure, French doors or sliding doors?

Both can achieve high security ratings with the right specification, including multi point locking and laminated glass, so security depends more on the specific hardware and glazing chosen than the door type itself.

How much space do bi-fold doors need to fold back?

Bi-fold doors typically need a stacking space equal to roughly 10 to 15 percent of the total door width to fold back against, which should be factored into the design when planning the opening.

Expert Insight

Installers report that bi-fold doors have grown significantly in popularity for kitchen extensions specifically, while sliding patio doors remain the more common choice for straightforward garden access where a full opening is less of a priority than cost and simplicity.

Final Thoughts

Choosing between French doors, sliding patio doors, and bi-fold doors comes down to how much floor space you can dedicate to the door swing, how wide an opening you want when fully open, and your property’s overall style. All three can deliver excellent thermal and security performance when specified well.

Comparing garden door options? Consider how you will actually use the space day to day, not just the widest possible opening, since a bi-fold door left mostly closed offers little practical benefit over a simpler, more cost effective option.