French door vs patio door: Trade installation tips

June 12, 2026

French doors suit homeowners who want a classic, outward-opening double door with full ventilation and a strong connection to the garden. Sliding patio doors are the better fit where floor space is restricted, the opening is wide, or a clean, minimal frame is the priority. Neither is universally better, the right choice depends on the opening, the property style, and how the client uses the space.

Specifying French doors and patio doors

When specifying external doors for residential or commercial projects, installers are often asked the same question: which is the better option, a French door or a patio door?

The reality is that there is no universal answer. The right solution depends on the property’s layout, available floor space, the client’s design preferences and how the opening will be used day to day.

For trade professionals, understanding the differences between these two popular door types is essential. From installation requirements and compliance considerations to thermal efficiency and aesthetics, your recommendation can have a significant impact on customer satisfaction and long-term performance.

In this guide, we compare the key differences between French doors and sliding patio doors, helping installers choose the best choice for every project.

French door vs patio door: what are the main differences?

The biggest difference between a French door and a patio door is how they operate. Traditional French doors consist of two hinged door leaves that open from the centre. Depending on the specification, they can open inwards or outwards, creating a wide opening and a strong visual connection between indoor and outdoor areas.

Sliding patio doors operate on a horizontal track system. Instead of swinging open, one or more glass panels slide behind a fixed panel, providing access without requiring additional swing space.

Feature	French Doors	Sliding Patio Doors
Opening method	Hinged doors	Sliding track system
Floor space required	Yes	No
Ventilation	Full or partial opening	Limited to active panel width
Glass area	Moderate	Larger glass panels
Style	Classic design	Contemporary design
Best suited to	Traditional homes and cottages	Modern homes and extensions

How do French doors and patio doors affect space planning?

Before specifying any door style, installers should assess how the opening interacts with the surrounding space.

Surveying for French doors

French doors require clear space for the doors to open fully. For outward-opening systems, check decking layouts, steps and level changes, and pathways. The benefits of French doors include a completely unobstructed opening when both leaves are open. This creates an open feel that many homeowners value during warmer months. However, the door swing must be carefully considered during the survey stage.

Surveying for sliding patio doors

Sliding patio doors are often the ideal option where space is limited. Because the glass panels slide within the frame, there is no need for clearance inside or outside the property. This makes them particularly suitable for:

• Tight spaces
• Open-plan extensions
• Apartments
• Commercial applications

Dekko’s Deceuninck Slider 24 system is available in two, three and four-panel configurations and can accommodate frame widths of up to 5932mm, making it a practical solution for wide opening applications.

Which door style provides more natural light?

Natural light remains one of the most important priorities for homeowners. For projects where glazing is a key consideration, sliding patio doors generally have the advantage.

Patio doors and uninterrupted views

Sliding systems, such as Dekko’s Deceuninck PVCu patio door, feature larger glass panels and slimmer framing, creating more natural light and more uninterrupted views. Premium aluminium frames can support larger panes of glass without increasing profile sizes, making them a popular choice for contemporary extensions.

Dekko’s Reynaers patio doors and Aluna aluminium sliding patio doors are designed to maximise glazing while maintaining excellent structural performance.

French doors and traditional aesthetics

French doors still provide generous glazing through multiple glass panes and large glazed areas. While the central meeting stile slightly reduces the overall glazed area, many homeowners prefer the balanced appearance and classic design offered by traditional French doors.

Dekko’s Infinity Flush French Doors are particularly well suited to projects where clients want authentic heritage styling without the maintenance associated with timber.

French door vs patio door: which offers better ventilation?

Ventilation is another important factor when comparing door types.

Airflow with French doors

• Open a single leaf for controlled airflow
• Open both leaves for a wide opening
• Create effective cross ventilation during warmer weather

This flexibility is one reason why French patio doors remain a popular choice for garden-facing rooms.

Ventilation with sliding patio doors

Sliding patio doors are limited by the width of the active sliding panel. Although ventilation is still effective, the maximum opening is generally around half of the total frame width. For clients prioritising airflow above all else, French doors are often the best choice.

Installation considerations for trade professionals

Proper installation is critical for long-term performance regardless of the door style selected.

French door fitting tips

When installing French doors:

• Check frame squareness before hanging leaves
• Confirm hinge positions are correctly aligned
• Verify smooth locking engagement
• Install opening restrictors where required
• Ensure threshold levels comply with regulations

Outward-opening French doors can be vulnerable to wind loading if left unsecured. Restrictors can help prevent damage and reduce future call-backs.

Sliding patio door fitting tips

For sliding systems, the most important factor is track preparation. Even minor deviations can affect easy operation and long-term performance. Installers should:

• Confirm the substrate is level
• Check lintel deflection tolerances
• Verify track alignment before glazing
• Test smooth operation before handover
• Ensure drainage channels remain unobstructed

Security features and compliance requirements

Security remains a key consideration for all external doors. Current Building Regulations require easily accessible doors on new dwellings to satisfy Part Q requirements.

Security requirements

Installers should specify systems that offer:

• PAS 24 accreditation
• Multi-point locking systems
• Toughened safety glazing
• Secure hardware and cylinders

Dekko’s Infinity Flush French Doors are PAS 24 accredited, while Reynaers sliding patio doors incorporate advanced security features designed for modern residential and commercial applications.

Building Regulations every installer should know

Compliance should never be treated as an afterthought.

Part L requirements

All new external doors must meet current thermal efficiency standards. Specifying high-performance double glazing and thermally efficient frame systems helps achieve compliance while reducing energy costs for homeowners.

Part M requirements

Accessibility remains a major consideration. Installers should ensure:

• Thresholds do not exceed 15mm where applicable
• Clear opening widths meet accessibility requirements
• Low-threshold systems are used where practical

Safety glazing requirements

Glass used in critical locations must comply with:

• BS EN 12600
• BS EN 12150

Always verify that toughened safety glass markings are present before installation.

Choosing the right material

Material selection influences appearance, durability and performance.

uPVC systems

uPVC remains the most widely specified material across many residential projects. Advantages include low maintenance, strong thermal efficiency, competitive pricing, wide colour selection and woodgrain finishes.

Dekko’s Infinity Flush range combines modern manufacturing techniques with the appearance of traditional joinery.

Aluminium systems

Aluminium continues to dominate premium installations. Benefits include slim sightlines, larger glass panels, fantastic durability, minimal maintenance and extensive colour range.

Dekko’s Reynaers and Aluna aluminium sliding patio doors are particularly well suited to larger openings where strength and aesthetics are equally important.

Looking for trade-ready French doors and patio doors?

Dekko supplies a comprehensive range of high-performance French doors and patio door options designed specifically for the trade.

From the Infinity Flush French Door range to Reynaers and Aluna aluminium sliding patio doors, every system is engineered to deliver exceptional thermal efficiency, security and long-term durability.

To learn more about Dekko’s door range or discuss your next project, contact our team for expert trade advice.

Frequently Asked Questions

Do French doors or patio doors need planning permission?

Replacing existing doors in the same opening is normally permitted development for houses in England. Installing French doors and sliding doors into an existing wall also falls within permitted development rights in most cases. If the property is listed or within a conservation area, always check with the local authority before specifying.

Which door type is better for a garden room or rear extension?

If space directly outside the opening is limited, go with sliding. If the client wants maximum ventilation, a stronger architectural statement, or the doors to open out onto a generous patio or decking area, French doors are a better match.

How do I advise a client who cannot decide between the two?

Ask how much outdoor space they have directly outside the opening, what is the style of their property style? Do they prioritise ventilation or maximum glass? French doors suit smaller patios, traditional homes, and clients who want to open both leaves independently. Sliding patio doors suit modern homes, wider openings, and clients who want to keep the internal floor plan unobstructed.