Bifold doors for easy inside-out living

As more and more of us have bifold doors installed and clever new alternatives appear on the market, these dreamworthy patio additions are becoming more affordable. So if you haven’t invested yet, now’s a great time.

Bifold doors will transform how you view and enjoy every inch of your outdoor space, sitting neatly out of the way when open so you can enjoy uninterrupted views of your garden and easy inside-out living. They also significantly increase indoor light levels, when open or closed, making your inside space feel far more airy.

Most installations will instantly recoup their cost and make your home more saleable as well as increasing its value. And with a host of designs, configurations, frame materials and finishes to choose from, there’s definitely a set of doors out there to suit your set-up.

What are bifold doors?

Unlike sliding patio doors, where the panels simply move across to one side and remain, covering part of the opening, bifold doors open concertina-style, folding flush to the side wall when fully open. This creates a single, expansive opening, meaning you can easily move between your home and garden and enjoy super-relaxed outdoor living.

Bifolds are made up of numerous glazed panels or doors that either hang from or sit on a track. Some tracks sit flush with the floor to create a virtually seamless transition between spaces. Not only does this look amazing, stretching the space and merging inside and out, but it can be hugely practical for those with mobility issues and who require wide openings and one-level access.

Supremely adaptable, besides being fully open or closed, they can be fitted so just a single ‘traffic’ door opens, which is ideal if the weather is less than lovely outside and you don’t want your open-plan kitchen or living area to be blasted with sudden Arctic temperatures. You can plan for this independent door to sit centrally as well as to one side, so you can align it with your existing kitchen or furniture layout and create an easy flow between areas.

What options are there for external bifold doors?

There are essentially four materials to choose from:

✽ Unplasticised Polyvinyl Chloride or uPVC is a low-maintenance, man-made alternative to wooden doors and windows. Relatively cheap to produce, the glazing and door units are extremely durable and need very little upkeep. All they require is a regular wipe-over with warm soapy water and they look as good as new.

Typically white, it is possible to order coloured uPVC bifolds, but you’ll pay a premium for the privilege. Besides limited finishes and profile styles to choose from, this synthetic material tends to expand in hot weather – as much as two and a half times more than aluminium – which can cause the doors to creak and stick.

✽ Aluminium is incredibly lightweight and strong. Resistant to heat and moisture, aluminium bifolds cope well with changeable climates and need next-to-no attention to keep them looking good. Choose from raw aluminium or powder-coated coloured and textured finishes.

Light to move, they work especially well for wider openings where numerous doors can be heavy and cumbersome to move, particularly if double- or triple-glazed. Aluminium is a poor insulator, though, so check that your product is fitted with a thermal break (an internal plastic barrier) that ensures the cold is kept out and that heat is retained inside.

✽ Hardwood designs ooze luxe living and the individual grain characteristics of this natural material look fabulous. Timber is a great insulator so it’s the best material to choose for thermal efficiency, but it doesn’t cope well with wet and varying weather conditions. The natural colour can silver over time and dirt and grime can quickly take hold, leading to mould and rot developing, eventually weakening the product. So regularly resealing the wooden frame every two to five years is a must.

✽ Composite or timber-clad aluminium doors are a happy combination of materials. They usually feature tough aluminium on the outward facing side and a more attractive wood laminate on the inside. With good thermal qualities, and being light and strong enough to accommodate triple glazing, they’re a popular choice. Many styles are available, including American white oak, pale larch and Nordic pine.

What’s your ideal fit?

Bifold doors come in configurations that usually range between two and six door panels. It’s possible to have more but the weight and thickness of the folded doors tend to become heavy to support and move. Look for a number in the product description: the first (larger) digit refers to the total number of doors, the second shows how many doors open to the left and the third figure indicates how many doors open to the right.

Doors can be fitted to fold in or out, so consider how much free floorspace you have available and whether you want them to take up patio or inside living space. Door frame widths vary depending on the chosen material and this will impact on the view when closed and the total thickness of the doors when folded open. Aluminium frames tend to be the narrowest so are often best for smaller, compact spaces.

Shop our pick of the best external bifold doors below

Top or bottom hung bifold doors?

There are two different ways to install these folding doors – top or bottom hung (aka bottom rolling). This refers to the positioning of the operating track or hinge and, although some systems also have a secondary guide track, it’s worth knowing how they operate differently.

Top-hung doors are suspended from a track fitted to the top underside of the opening. Although less stable and trickier to fit than bottom-rolling designs, top tracks minimise the mechanisms on the ground for a sleek look. ‘Captive rollers’ give the smoothest action.

As the track supports the doors’ weight, it’s crucial that it’s firmly attached to a secure and strong lintel – the timber, concrete or reinforced steel joist (RSJ) that spans the width of the opening. Structural engineers recommend a heavy-duty or rolled steel lintel to minimise the chance of any flex or bending which would prevent the doors from gliding smoothly open.

Bottom-hung doors have their track fixed to the floor. Easy to adjust, they provide a stable and smooth gliding motion. This is particularly important with doors made from heavier materials or with numerous panels.

While it is possible for the track to fit flush with your floor, in some cases it can be tricky to do while also ensuring sufficient weather protection – your retailer or a structural engineer should be able to advise you on what’s achievable for your installation. It might be that a slight lip ranging from around 12-50mm is needed to seal the door from wind and rain.

How big?

Getting the correct fit needs to be evaluated on a case-by-case basis – your retailer or a structural engineer will be able to advise you. Some companies include installation in the product price while others offer self-installation products.

If you are a competent DIYer, it’s a doable task but you will need to be meticulous with measurements and make sure that the opening is exactly level and at right angles. You also have the option to call a builder in to do the job – expect to pay from £800.

Bifold doors are normally included in a property’s permitted development rights but if your home is listed or in a conservation area, or if you are creating a brand-new opening in any age home, you will likely need planning permission. So before starting any work or placing an order, do check with your local council – find yours at gov.uk/find-local-council.

Shop our pick of the best swish bifold door alternatives

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