For the last decade, we’ve seen the trend for bi-fold doors steadily incline as homeowners remain loyal to flooding social areas with natural light and continue to love seeing their garden as an extension of their living space rather than just a separate, isolated area. The amount of glazing within folding doors allows dwellers to create a seamless transition from home to garden, as well as the desired illusion of extra space, by simply allowing the outside in.

As joiners, high quality, bespoke wooden bi-fold doors are one of our specialities. We naturally get asked a lot of questions about wooden folding doors, so we thought we would share our answers to the most commonly asked ones, to help anyone thinking of investing in timber bi-fold doors for the first time to find the information they are looking for.

Are wooden folding doors the same as bi-fold doors?

Yes. Wooden folding, bi-fold, and concertina doors all refer to the same thing… wooden doors that fold in or out in order to open up space. They are typically glazed with large glass panels to allow plenty of light in from the outside or to filter light through to an adjoining room. The door and its connected door panels usually fold up by gliding along a simple tracking system, and stack against the wall in order to optimise space. The door itself will also serve as a traffic door for popping in and out on a daily basis if you are not wanting to slide the whole door system open completely. Most bi-fold doors will have anywhere between two and seven panels, all of which will be connected with hinges and attached to the roller track at the top or bottom of the door.

What is the difference between external and internal bi-folding doors?

External folding doors will typically be found at the back of the house, leading to the garden. They are great for connecting a property’s inside space with the outside, allowing a garden to look like an extension of the adjoining living/kitchen space.
Internal folding doors are a good solution for covering smaller spaces like wardrobes, utility rooms, or where the option to section off a room is preferable. If privacy is needed, internal doors can be solid (with no/minimum glazed elements within the design). However, if internal bi-folds are required for interconnecting rooms, you may decide to choose glazed panels to help light filter through into both areas.

What type of wood is used for bi-fold doors?

External doors need to be able to endure harsh weather conditions and avoid the risk of decay, therefore using a hardwood is advised. Here at Parsons, we can construct folding doors from various types of quality timber but tend to use Merani and Oak hardwood the most. All our timber is sustainably-sourced from FSC or PEFC certified forests. We use Teknos low VOC paint and treatments for all our wooden folding doors. Prior to painting, we use a Teknos End Grain Sealer which seals the wood on the face/end grain and prevents it from starting to dry. This also aids the paint to dry evenly on the timber.

We follow this up with two coats of Teknos Water-Based Primer (ensuring that the timber fully dries between coats for ultimate protection). Lastly, two coats of Teknos Water-Based Topcoat are applied, and we are very careful to check the doors between coats to ensure full adhesion and protection.

Can wooden folding doors house double glazing?

Yes, the glass panelled elements of wooden folding door sets can be double-glazed. In fact, we craft all our external doors with double glazed units as a standard unless you tell us otherwise. We can also double glaze internal doors if required.

What are the benefits of wooden bi-folds?

There are many reasons why wooden bi-folds are more popular than aluminium/uPVC alternatives, including:

  • Low energy production
    unlike steel or plastic, timber requires a relatively small amount of fossil fuel energy to convert it into useful products. For example, a uPVC window frame uses more than seven times the energy input in manufacturing than a wooden window of similar size and design.
  • Good thermal insulation
    the cellular structure of wood means it naturally creates a barrier between heat and cold resulting in a better thermal performance than aluminium framed windows.
  • Weather resistance
    we offer durable wood species and use preservative treatments. With simple maintenance, your windows will last you a lifetime.
  • Aesthetic charm
    bi-fold doors can be made to suit your period property. Wood oozes aesthetic charm that cannot be matched by any rival material which makes them ideally suited to period homes.
  • Timber is incredibly customisable
    not only can you choose a different colour for the interior and exterior of the door, but you can easily sand and repaint wooden doors if you want to change your decor. Simply specify your perfect bi-fold doors and we will make them bespoke for you to match your style. Alternatively, we can provide your bi-folds unfinished, allowing you to stain, varnish and paint if preferred.
    When it comes to painting bi-fold doors, we can offer both traditional brush finishes and smooth, modern spray finishes depending on the aesthetic you prefer and the type of property you have. Owners of period properties for example, tend to opt for a brush coated finish to aid authenticity and replicate the properties original appearance. Modern property owners however, often prefer a spray paint finish for a smooth, perfect appearance with no brush strokes.
    As standard, we use White Gloss or White Satin on our doors, but you are very welcome to choose a colour from you preferred paint brand. We can colour match any colour for you and are happy to custom the internal and external woodwork to complement differing interior and exterior styles.
  • Good sound absorption
    wood is great at absorbing sound to help create a quieter room.

Which is better, bi-fold doors or French doors?

The answer to this question is not straightforward. It will depend on what you’re looking to achieve and what kind of property you own.

Bi-fold doors feature multiple panels which can open up an entire wall without any obstruction.
If your main priority is preserving space, you may lean towards bi-folds as your preferred option as there is no protruding door when the doors open.
The adaptability of bi-folds also mean that the panels can be designed in a way that is space conscious.

French doors are significantly easier to install as their design is straightforward and therefore, can be installed in more situations. French doors have a classic appeal to them which should be considered. Plus, they may be suitable for more locations within your property, but that does not mean they will necessarily suit every situation. French doors tend to cost less than bi-folds as they are not made up of so many components, but if French doors do not suit the style and aesthetics of your home, they may possibly devalue it.

We will always send an experienced surveyor to your property who can advise on the best options for you, we work with a wide range of property types and have the experience to offer you sound advice. We can advise if wooden bi-folds are the right option for you, or whether French doors could be a better choice with the space you have available. We craft everything bespoke, so awkward spaces are never a problem for us, and we can also accommodate top hung doors (which run along the top track rather than the bottom) as an option too if you prefer this configuration.

Which is better, bi-fold doors or sliding doors?

Similar to bi-fold doors, sliding doors offer an open view of your garden and are made of larger panes of glass compared to bi-folds. However, they cannot be fully opened in the way bi-fold doors can, compromising their versatility.

Can wooden folding doors fold back against a wall?

Yes. When fully opened, wooden bi-folds take up little space while opening up your wall completely. Their unique design allows them to fold-back on themselves like a concertina. They complement both large and small homes.

Are wooden folding doors energy efficient?

With energy prices continuing to rise it makes sense to try and reduce the amount we use, both for the sake of the planet and our purse strings! As glazing takes up the majority of space on a bi-fold door, the glass used will obviously have the biggest impact on thermal efficiency, but the frames can also impact the thermal performance overall. When we talk about measuring how effective a material is as an insulator (and therefore how successful it is at reducing heat loss), we measure its success in U-valves.

Building control currently require bi-folds to have an overall U-value of 1.8W/m2 or less. The overall U-valve target should be for the glass and framework combined. Simply put, the lower the value, the better the material is as a heat insulator.

All of our external wooden bi-fold doors are compliant with UK building standards and achieve the required U-valve targets. We also responsibly source our timber from reputable suppliers. We endeavour to source all wood form either independently certified sustainable forests, or from suppliers who have been independently verified to ensure their timber is traceable. This ensures they get their timber from legally harvest forests. Doors fitted and crafted by our team means you can rest assured that they will not only be constructed from high quality materials, but they will be sealed and treated professionally to provide ultimate protection from the elements.

Do you have bi-fold doors that need replacing?

If you have older bi-fold doors with damaged/older glazing, or you have been experiencing some draughts, warping, cracking, or stiffness lately, it may be time to replace them. Luckily, we can replace existing doors that are made from timber, as well as those made from uPVC or aluminium. Technology has advanced considerably in recent years and replacing older doors and glazing with new ones can dramatically improve the warmth of your home. Similarly, if you have old-fashioned sliding patio doors, a side hinged door, or French doors, we can replace these with beautiful bi-folds too.

Are wooden bi-fold doors secure?

Yes, wooden bi-folds are very secure. Unlike your typical back door that only has one lock on it, our external wooden folding doors boast a multi-point locking system as well as internally beaded frames and high-security hinges. You also have the option of fitting childproof locks to prevent your doors being opened by small children. Opting for toughened glass in the door panels is another popular choice among our customers. Toughened glass has undergone a heat treatment to strengthen it so, if it does break (which is less likely than with normal glazing), it doesn’t shatter or splinter.

How much do wooden bi-fold doors cost?

At Parsons Joinery we focus on bespoke external wooden bi-fold doors only with the price starting around £3,000 for a two-leaf bi-fold door. Generally speaking, the price increases by around £1,500 per additional door leaf that is added.

Contact us

Contact us – we can answer all your questions and will be happy to book a free, no obligation consultation.
Call 01273 814870 or email