What is best? French Doors, Sliding Doors or Bifolding Doors?

For new extensions or replacing dated patio doors, there’s a choice of French Doors, sliding doors or bifolding doors. As well as this is slide and turn doors offering a different patio door experience. Whether you choose hinged, sliding, folding or stacking doors, each has its benefits and, in many cases even suit the same door opening sizes. Here’s everything you need to know when trying to decide between French Doors vs sliding doors vs bifold doors.

french doors, sliding doors or bifolding doors shown in a large sitting room
French doors, sliding doors or bifolding doors? All these great patio door types come with different features and benefits

Why your property affects your choice of French doors, sliding doors or bifolding doors

First of all your choice between French doors, sliding doors or bifolding doors depends on your project. Are you replacing an existing set of doors for something more modern or building a new opening?

Naturally for the latter, there’s more flexibility as you get to choose how large the opening is and size can also influence the choice of sliding doors or bifolding doors. For an existing opening, you’re limited by the size you have.

There are other considerations such as the sightlines you’d prefer, whether you want to reduce the visible aluminium and maximise the glass. Of course, patio doors also mean enjoying warmer days better and having these open up in the right way, connecting your room to the garden, patio or balcony. However, with your doors closed for most of the year, do the views and light you get from a closed set of doors matter more?

Your other consideration with choosing between French doors vs sliding doors vs bifold doors is how these are used day-to-day. For instance, if you live in a home with only one patio door, functionality becomes more important than a larger home with more than one door on the ground floor.

We’ll help navigate all these considerations in this article.

Choosing French doors, sliding doors or bifolding doors for an existing opening

Replacing your old patio doors? The size of your structural opening isn’t too restrictive these days as French doors, sliding doors or bifolding doors come in configurations for smaller doorways. So let’s take a look at the options for an existing opening.

For door openings up to two metres

If your door opening size is around two metres or slightly more, then your best choice is French doors. Any size under 2m wide is best with French doors. From 2m wide to 2.5m wide, French doors with one or two sidelights are best.

There’s also for existing openings of these sizes, a two panel sliding door. You could go with a bifold, however, bifold doors in an even number of panels and folding in one direction aren’t always the best. You’re restricted in the locking options and many products need an additional bolt-on section on the one side called a floating mullion. These floating mullions make the aluminium thicker on the locking side and can look uneven.

One type of French door for regular openings you may not be aware of is the French door made with bifold door profiles. Origin OB-49, Smart Systems Visofold 6000, Solarlux Ecoline, Sunflex SF55 or even the super slim Sieger Lux are the thinnest bifolds on the market. There’s no reason these can’t be made as hinged double doors often coming in slimmer than regular aluminium French doors. Get in touch if you need more information on these types of doors and how they work.

For door openings over two metres

For opening sizes above two metres to around four metres, you now get the choice of how many panels you want in your doors. When it comes to the least amount of aluminium and the most amount of glass, nothing beats a sliding door. Two panel or three panel doors are the best looking giving you just one or two visible vertical mullions. The end result with a large two-panel sliding patio door creating a wall of glass with just one thin middle mullion is very impressive.

For French doors in openings between two and four metres, double doors with one or two side panels work best. And if you go with any of the steel-inspired double door products, these look slim and on-trend. You don’t need to have the bars and grid pattern on these, giving you thin and very attractive French Doors.

For larger door openings over four metres

Any existing openings over four metres extend your options even more. Now you can benefit from slimline sliding doors, standard or wide-panel bifolds and slide and stack doors.

One recommendation if space on the patio area allows is a wide-panel bifold. The Schuco ASS70 FD HD goes up to 1.5m wide panels. These are an excellent solution for door openings often needing four panels but offering a solution with three. Even better is the look of these doors closed with just two vertical mullions and looking like a sliding door yet with all the advantages of a bifold. A similar product is available from Express Bifolds using the Alumil system.

french doors in white at the back of a new extension

Four reasons to buy aluminium French doors, sliding doors or bifolding doors

You’ll get a reliable, secure and weather-resistant door whether you go with aluminium, PVCu, timber or even hybrid doors combining two materials. However, aluminium beats all these materials in four significant areas.

If you are considering PVCu, timber or composite materials, we’ve create a helpful guide on choosing the most suitable door.

1. You get slimmer frame lines

When it comes to what doors are the slimmest, it’s hard to beat aluminium. PVCu is always thicker as it needs this bulk for strength and security. Timber is a wonderful natural material but this too is usually thicker than any standard aluminium patio door set.

So if reducing the visible sightlines of essential frame profiles matters, aluminium is the slimmest when choosing French doors, sliding doors or bifolding doors.

2. Larger doors, more glass and more light

Aluminium doors typically provide larger door leaf sizes than PVCu and timber doors. Most other materials give you door sizes of around 850mm – 900mm. Aluminium doors go well over 1m width with most systems.

It’s the same for the heights. For most 2300mm or taller openings, other doors mean you need a glazed light above them. Choose the right aluminium door and it’ll comfortably cover this height. The benefit is fewer aluminium profiles, larger glass sizes, more light and better views.

3. You can match other aluminium doors

What you might not know is aluminium gives the best solution for matching both French doors and bifolding doors.

You may have a larger extension with bifolding doors for your living area and a nearby study or dining room also leading to the garden. It’s possible to make single doors or French doors out of the same profiles as bifolding doors. The benefit therefore is matching doors where you need these three different types.

4. More choice of designs with aluminium

Aluminium doors come with a substantial choice of colours. That said, colour and glass technology is available with aluminium, PVCu and timber too. So for popular and trendy shades, they come with all types of patio doors.

Aluminium goes one better with more distinctive shades. Textured, metallic or anodised are three types of finishing you can’t get with timber or PVCu.

Even better with aluminium is the design choices. There are minimalist and slimline solutions for patio doors, even frameless. Steel-inspired, Art-Deco and industrial looks are only possible with aluminium or genuine steel product.

As well as this aluminium provides more opening choices with sliding or folding doors such as slide and stack doors, pocket sliding doors and doors with fully open corners.

solarlux wood bifolding doors

French doors, sliding doors and bifold doors explained.

In this section, we provide even more information on each of these different patio door products.

French Doors

French doors you may know as a set of double doors that most people choose to open outwards although of course, they can open in if you wish.

Double French Doors will be more suitable to the smaller structural openings, but aluminium french doors are better than PVCu French Doors because they can be made taller and wider.  This is good news if you have a typical 2400×2300 structural opening that PVCu doors can only go into when coupled to sidelights and toplights.  This means more bulky PVCu sections, less glass and a smaller door area.  Don’t forget that the sidelights and toplights add to the cost of a set of doors as well.

In aluminium, however, French Doors can be manufactured at maximum sizes of 1260mm wide for a single door and at least 2460mm wide for french doors.  Aluminium French Doors can also be made substantially taller than most PVCu doors at 2400mm high negating the need and the additional cost of a toplight.  Some other doors can also be built taller than this if needed.

French doors with most quality systems will meet high security using multipoint locking, and many have passed the latest PAS024 security tests.  Additionally, with aluminium french doors you will get substantially thinner profiles than any PVCu door meaning more glass area and less aluminium.

The advantage of french doors over patio doors is that if they are your only access door into your garden, you can use only one leaf instead of both.  In the summer you have the option of opening both door leaves, and if needed these can be fitted with integral door restrictors.

The good news with French Doors is bifolding door profiles can be used to create them.  Origin offers French Doors matched to their bifolds, and this arrangement is available with virtually any bifolding door system too.

Reasons to choose a French Door

French doors are ideal for smaller openings. They’re the most affordable option for aluminium patio doors and when choosing between French doors, sliding doors or bifolding doors on price. Choose a French door for smaller openings, for a more timeless design and where your property matches these doors better.

  • They are familiar to use for young and old
  • French doors allow you to use your doors as access doors from outside
  • These doors look fantastic when designed in an Art-Deco or steel look
  • A transformation when replacing thick chuncky PVCu French Doors
patio doors by sunflex

Sliding doors

The most significant advantage of patio doors and sliding doors is that because they slide on one track, they take up less space when open than French Doors or bifolding doors.  If you have a tiny patio or even a balcony, patio doors will make more sense.  Additionally, they will not be prone to blowing open or closed on very windy days like any swing type door.

Modern patio doors in aluminium now come at substantial sizes typical of the big glass sliding doors that you will have seen on Grand Designs.

Patio door technology has advanced quite significantly in recent years.  With a modern sliding door, you get one, two or three tracks.  These tracks enable the various door leaves independent sliding, also providing options on how you open your doors.

Patio doors are generally available as two, three or four pane sliders although custom doors with more panels are available.  The slim aluminium profiles now mean that even two-pane patio doors come suitable for doors up to five metres wide.  There are even sliding doors such as the Dutemann going up to 6.7m wide with just two panels. As a result, you benefit from impressive views thanks to the expansive glass area, and with minimal visible aluminium.

Sophisticated hardware and rollers in modern aluminium patio doors mean that while some considerable patio door leaves can weigh several hundred kilos, they remain remarkably light to use and slide daily.

Some patio door systems can go up to three metres in height as well giving you huge doors if you are building a bespoke opening.

Patio doors also have sophisticated security built-in with protection where the door panels overlap and excellent multi-point locking systems.

Reasons to choose a sliding door

Thinner, more attractive and more functional than older generations of patio doors. Sliding doors come with specific advantages when choosing between French doors, sliding doors or bifolding doors. Choose sliding doors when the light, a feeling of space and a fully open aspect even with the doors closed matters. If you live in a property benefitting from great views, sliding doors are a bettter option too.

  • Sliding doors come with the thinnest middle mullions starting at 19mm
  • Only sliding doors provide the largest glass sizes and fewest visible profiles
  • They take up no space inside the room or outside on the patio when open
  • They come in two different sliding options
origin bifold doors cost

Bifolding Doors

Bifolding doors are to many the ultimate door for the back of the house and obviously offer features that the other two types of doors cannot.  The biggest advantage is when fully open they open up the entire building opening to create a fantastic open space and a seamless transition between the inside and the outside of the house.

There are now many configurations of bifolding doors giving you flexibility in how they open.  If you have a simple 2 metre wide opening and wish to replace old french doors or an old two pane patio door, you can have two pane bifolding doors that concertina open.  But on a two pane door when they are open they won’t give you a much bigger clear opening than two french doors fully open. 

The advantage is that you will only have open doors on the one side instead of both sides with french doors. You will also lose the flexibility of only opening one door as you can with French Doors.  Therefore, take a look at how bifolding door sizes in relation to French or sliding doors may affect your choice.

Again if your bifolds are the only access door into your garden, we strongly recommend one swinging access leaf opening on the one side with the rest of the bifolding doors sliding open on the other side.  This will enable you to simply swing open one door if you wish to take the rubbish out or on winter days without having to slide every door open.

Bifolding doors provide the best of all worlds when configured and designed correctly but are ideal where the open doors won’t encroach on the outside space and where the structural opening is big enough to accommodate them.  If you have an existing opening of 2700mm or more there is no reason why you cannot have bifolding doors.

Reasons to choose a bifold door

A bifold door provides the best solution for everyday access and opening up your room to the outside space on warmer days. If these two features matter the most then it’s the preferred option when deciding between French doors, sliding doors or bifolding doors. We recommend a bifold for smaller properties as they also give the illusion of a larger room when open.

  • A functional as a French door when configured with a traffic door
  • Flexible sizes and panels make it ideal for all types of openings
  • The best door type to fully open up a door aperture
  • Substantial number of products to choose from
solarlux bifolding doors review
Solarlux bifolding doors in the steel-look design

How to decide between French doors, sliding doors or bifolding doors.

Aside from any limitations with an existing opening if you’re still not sure what’s best, here are where bifolding doors, sliding doors and French doors differ.

When you want the slimmest sightlines go with sliding doors

For the thinnest possible aluminium and even door frames hidden in the structure for a near frameless look, only sliding doors are best.

French doors and bifolding doors don’t come with the 20mm mullion options of sliding doors and French doors can’t get the flush threshold possible with sliding or folding doors.

For getting an entire door opening, choose bifolding doors

Unless it’s a new extension and you design sliding doors with the pocket option and doors sliding into the wall, only bifolds will give you the maximum clear opening. Therefore these doors are ideal for smaller homes giving the illusion of more space with the doors fully open.

Need to make the most of great views? Sliding doors are best

Sliding doors come with glass sizes wider and taller than any bifold or French doors. Therefore, when you have a great view, a larger garden or even a penthouse apartment, there’s no better product for making the most of any great view than sliding doors.

If getting the most out of the winter months is also important, again sliding doors are probably best. When the doors are closed you enjoy fewer vertical mullions, more light during the shorter days and an altogether brighter feeling in the room.

When you want the best in steel-look doors, choose French Doors

Whilst bifolding and sliding doors all come in a steel-look style, only French doors deliver better aesthetics.

French doors in smaller openings look great in the steel look. Larger openings easily accommodate a set of double doors with side panels. Even larger openings mean more than one set of doors with side panels if needed. There’s nothing better for getting the Heritage, Art-Deco and industrial look than French doors.

french doors, sliding doors or bifolding doors explained


Ultimately your choice of the best patio door depends on budget, personal taste and the overall look you want to achieve.

If budget isn’t the deciding factor, we suggest choosing your doors based on the sightlines you want, the appeal of the larger glass panels in sliding doors or how much of the available opening you want.

And if you’re lucky enough to have more than one door opening at the back of the home, mixing these different doors also creates a great end result.

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