There’s a lot to love about bifold doors. They give you unobstructed sunrise views every morning, allow for easy access to your garden spaces, and add significant financial value to your property. In fact, we’ve just written all about the benefits right here.
However, whilst all of this is important, we’re being asked more regularly than ever about the thermal performance of these doors. It’s natural to question it, people see large expanses of glass in place of where a wall once was, and wonder if it’s actually costing more to keep your home warm.
The good news is that energy efficient bifold doors are now readily available, regardless of frame material. Thermal break technology, solar glass, and tight seals are all designed to reduce heat transfer, in practice making your home cooler in the summer and warmer in the winter.
This means that you can enjoy a more light-filled space without worrying about temperature swings or rising bills, and truthfully they compete with just about any door when it comes ot thermal efficiency.
To ensure you choose a bifold door that keeps the heat in, we’ve put this blog together.
Emphasising the importance of thermal performance
Thermal performance is simply how well a door stops heat from escaping or getting in. Heat naturally moves from warm spaces to cooler ones. This is called heat transfer. With external doors like bi-fold doors, poor thermal performance means warm air leaks out in winter and hot air pours in during summer.
A well-made bi-fold door, with a variety of features that we’ll touch on below, slows this heat flow down. That keeps your indoor temperature steady all year round, which is good news for comfort and your energy bills.
The benefits of good thermal performance include:
- Lower heating bills in the colder months
- A cooler, more comfortable home in summer
- Reduced energy consumption and a smaller carbon footprint
- A more stable indoor temperature throughout the day
- Genuine energy savings over the life of the door
Energy efficient bifold doors: what to look out for
The market is flooded with bi-fold doors, and they differ quite a bit. To make sure your space stays comfortable, here’s what to look for.
Thermal breaks
A thermal break is a barrier built into the aluminium frame that stops heat from passing straight through the metal. Our PlusFold system uses a 30mm polyamide thermal break, which makes a real difference to heat retention.
U-values
A U-value measures how much heat a door lets through. The lower the number, the better. Our standard system hits 1.4 W/m²K, comfortably meeting UK building regulations. Our high-performance Modeal profile reaches an exceptional 0.93 W/m²K.
Double and triple glazing
The type of glazing matters enormously. Because of the amount of glass and its placement, single glazed units don’t cut it for this external door. Instead we offer thermally efficient double glazing as standard, with triple glazing available for maximum thermal insulation and noise reduction.
Weather sealing and thresholds
Airtight seals keep draughts out. Our doors are tested up to Class 9A water tightness, with threshold options to suit exposed or sheltered locations.
Solar control glass
For large glass panels facing south, solar-control glass reduces unwanted solar gain and stops rooms overheating in summer.
Comparing aluminium to other bi-fold door materials
Material choice shapes the overall value of your new bi-fold door. Here’s how the three main options stack up.
| Feature | Aluminium | uPVC | Timber |
| Thermal efficiency | Excellent | Good | Good |
| Lifespan | 30+ years | 20-25 years | Variable |
| Sightlines | Slim, large glass panels | Bulkier frames | Chunky frames |
| Durability | Outstanding | Solid | Prone to warping |
| Maintenance | Low maintenance | Low | High upkeep |
Aluminium is our top pick for strength, slim frames and an abundance of natural light. uPVC is a reliable budget-friendly choice. Timber, while charming, needs regular care to stay weatherproof.
What are the other benefits of bi-fold doors?
We’ve recently produced a full guide on this, which you can find on our blog. To quickly recap, the main benefits include:
- Floods of natural light into your living space
- An unobstructed link between indoors and the garden
- Added property value for potential buyers
- Flexible configurations to suit any opening
- Modern aesthetic appeal that suits any home
Aluminium bi-fold doors from BSF Windows
Our doors blend excellent thermal efficiency with lasting good looks. With low maintenance frames, slim sightlines and impressive energy savings, they offer comfort and kerb appeal that genuinely adds value to your home for years to come.
Our range is packed with choice. You can pick from almost any RAL colour, including dual-colour frames with one shade inside and another out. Glass options run from double to triple glazing, plus solar-control and acoustic upgrades.
On security, the doors are tested to PAS 24:2022 and can be built to Secured by Design status. We also include finger-safe gaskets, so little hands stay protected. Need to nip to the garden? A traffic door lets you pop out without folding back the whole set.
Who are BSF Windows?
We’re a family-run window supply and installation company with over 20 years of experience. From our showroom at 31-33 Station Road, Horley, we serve Crawley, Guildford, Dorking, Brighton and beyond.
Ready for a perfect fit and professional installation? Call us on 01293 408 713, email bsfwindows@gmail.com or pop into our showroom for a free quote today.
