French Doors or Folding Doors? How to Pick the Perfect Portal Between Inside and Out

When planning how to connect your indoor and outdoor spaces, the decision often comes down to three main contenders: French doors, folding (bifold) doors, and sliding doors. Each has its strengths – aesthetically and functionally – but choosing the right system involves far more than just picking what looks nice in a showroom.

From door swing to threshold height, panel stacking to insect protection, this guide unpacks the key things to consider before making a decision. I’ll also share what I chose for my own home – and what I would do differently next time.

Understanding the Main Door Types

French Doors

Two hinged doors that swing open from the centre, typically outwards. French doors are often used in smaller openings and suit traditional or cottage-style homes. They’re relatively simple to install and have an enduring charm.

Pros:

• Symmetrical appearance

• Easy to operate

• Good for ventilation

• Compatible with fly screens

• Generally more affordable

Cons:

• Only suitable for smaller openings

• Framing interrupts views

• Limited wow-factor in open-plan spaces

Folding (Bifold) Doors

Multiple glass panels hinged together that slide and fold to the side. These systems can open up entire walls, making them ideal for maximising flow between inside and out.

Pros:

• Fully openable wall for seamless connection

• Great for entertaining and open-plan living

• High impact visually

Cons:

• Higher cost

• Can interrupt view when closed due to more framing

• Requires stacking space

• Not all systems support fly screens

Sliding Doors

Panels that slide over one another along a track. They offer large expanses of uninterrupted glass but don’t open as widely as bifolds.

Pros:

• Clean, minimal sightlines

• Easy operation

• Works well in tight or windy areas

Cons:

• Only partial opening (usually half the total width)

• Less ventilation flexibility

What I Chose: A 4-Panel Folding Door with a Separate Traffic Door

For our renovation, I chose a 4-leaf outward-opening bifold door system – made from wood. Initially, I had my heart set on steel-framed doors for their clean lines and timeless appeal. But in the end, I changed course for two reasons: the lead time was far too long, and I was concerned about steel’s tendency to transmit heat and cold – not ideal in a home where energy efficiency matters.

Instead, I opted for timber frames and painted them black to create that same steel-look aesthetic, but with better thermal performance and more flexibility. Choosing wood gave me more room to adapt the sizing and incorporate details like the transom windows above, which wouldn’t have been as easily possible with rigid steel profiles.

The doors open outward to avoid disrupting the interior layout, and I included a separate traffic door for daily access – highly recommended if you don’t want to swing open the entire system every time you step outside.

Height, Weight and Why I Added Top Windows

Initially, I wanted the doors to go as tall as possible to bring in more light. However, I quickly discovered that bifold panels can’t exceed around 2.4–2.5 metres in height without becoming prohibitively heavy. Beyond that, you’re looking at additional structural support, premium hardware and more labour – which wasn’t feasible in our case.

Instead, we added fixed windows above the bifolds (also called transom or clerestory windows), which brought in the light I wanted without overloading the door system. It’s a neat solution if you’re facing height limitations, and aesthetically it helps avoid a stunted or chopped-in-half look.

The One Thing I Missed: Insect Screens

This is my biggest regret. I live in a region where warm days mean open doors – and unfortunately, open doors mean insects. I didn’t realise until too late that many bifold systems, especially those opening outward like mine, do not support integrated fly screens. Retrofitting them is tricky and often unsightly.

If I were starting again, I’d prioritise a door system that could incorporate a flush, retractable insect screen – ideally one that slides across discreetly when needed and disappears when not.

Credit: Homepoint

Key Practical Considerations

1. Width and Height of Opening

• French doors suit openings up to around 2.2m

• Bifold systems can cover 4–7m or more

• Sliding doors are often ideal for openings around 3–5m

• For taller installations, consider transom windows if structural support is a concern

2. Panel Configuration and Opening Direction

• Bifold doors can be configured as all panels folding one way (e.g. 4+0) or split (e.g. 2+2)

• You can choose inward or outward opening – I chose outward to protect the indoor layout

• Think about where the panels stack when open, and whether they will obstruct furniture or pathways

3. Everyday Access (Traffic Doors)

If you don’t want to open the entire bifold just to let the dog out, install a dedicated traffic door. These open independently like a normal door and make daily life much easier.

4. Ventilation and Use

French doors and traffic doors are best for quick airflow. Bifolds and sliders tend to be all or nothing unless designed with partial opening in mind. If you like having the doors open just a crack, plan for this during selection.

5. Thermal Performance and Weather Sealing

• Low U-values (ideally 1.1 W/m²K or lower)

• Thermally broken frames (especially with aluminium)

• Multi-point locks and weather-resistant thresholds

6. Fly Screens

Ask early whether the door system you’re considering can support integrated fly screens – especially if you live near water or in a buggy area. This detail is often overlooked.

7. Material Pros and Cons

• Timber: Natural insulation, aesthetic flexibility, easier to customise, but requires maintenance

• Aluminium: Sleek and strong, low-maintenance, but requires thermal breaks to avoid heat/cold transfer

• uPVC: Affordable and practical, but bulkier and not ideal for large openings

8. Threshold Design

• Flush thresholds provide seamless transition but may compromise weather resistance

• Raised thresholds offer better protection from rain and draughts

9. Glazing and Security

• Consider double or triple glazing, Low-E coatings, laminated glass for security

• Multi-point locking systems and anti-lift tracks provide peace of mind

10. Installation Tips

• Ensure frames are properly sealed and aligned – timber may need additional treatment

• Structural beams or lintels are often needed for wider openings

• Flooring must be levelled correctly for smooth operation

Cost Comparison (Estimates)

French Doors:

• €1,500–€3,000 / £1,300–£2,600 / $1,600–$3,200

• Easier and cheaper to install

• Suitable for most homes with smaller openings

  
  

4-Panel Bifold Doors:

• €4,000–€8,000 / £3,400–£6,900 / $4,300–$8,600

• Price depends on size, material, glazing, and brand

• Additional costs for installation, lintels, transoms, and custom thresholds

Sliding Doors:

• €2,500–€6,500 / £2,200–£5,600 / $2,700–$7,000

• Typically less complex than bifolds

• More frame visible when fully opened

Final Thoughts

If I were doing it again, I’d choose a system that allows for integrated fly screens.

If you’re trying to create a seamless connection between indoor and outdoor living, the door you choose plays a crucial role in how the space feels – and functions – year-round.

French doors are charming, functional, and affordable. Folding doors make a big visual impact and are ideal for large openings, especially if you want to create a real sense of openness. Sliding doors offer a sleek alternative but can limit access and ventilation.

Personally, I love the light and openness my bifolds bring, and the outward-opening configuration was the right call for our layout. Choosing timber gave me control over the finish and sizing, and painting them black gave me the steel look I originally wanted – without the thermal or timing compromises.

But if I were doing it again, I’d absolutely choose a system that allows for integrated fly screens.