Bi-Folding Doors
BI-FOLDING DOORS
Aluminium & uPVC Bifold Doors, Supplied & Fitted in South London
Imagine folding away an entire wall of glass and letting your kitchen flow straight into the garden. That's what a well-fitted set of bifold doors does — and it's why they've become the most requested upgrade for extensions across London. At 4 Moon Windows, we supply and install both bi fold aluminium doors and uPVC bifold doors from our base in Thornton Heath. Whether you want the ultra-slim frames of a premium Cortizo system or a budget-friendly uPVC option, we'll fit the right doors for your home and your wallet. Every set is made to measure, installed by our own team, and covered by a full guarantee. No subcontractors. No surprises.
Premium Quality
Top brands and high performance systems
Energy Efficient
Advanced thermal-break technology delivers energy efficiency.
Enhanced Security
Enhanced security features with multi-point locking and shoot bolts.
Up to 14 Panels
Create expansive openings with flexible folding configurations.
BI-FOLDING DOORS
Aluminium or uPVC Bifold Doors — Which Is Right for You?
Bi Fold Aluminium Doors: Slim, Strong, Built to Last
Aluminium bifold doors are the premium choice, and for good reason. Aluminium is far stronger than plastic, which allows much slimmer frames and bigger panes of glass. The result is more daylight, cleaner sightlines, and that striking modern look you see in high-end extensions. Thanks to modern thermal break technology, today's aluminium doors are also highly energy efficient — the old idea that metal frames are cold is simply outdated. Add powder-coated finishes that resist fading for decades, and aluminium becomes the smart long-term investment.
uPVC Bifold Doors: Practical Performance on a Budget
uPVC bifold doors cost noticeably less than aluminium, and their multi-chambered frames provide naturally good insulation. For smaller openings — two or three panels — they're a perfectly sensible choice. The trade-off? uPVC frames are chunkier, come in fewer colours, and can flex on very wide spans. If your opening is over three metres, or you want the slimmest possible frames, we'll usually steer you toward aluminium. But if budget is the priority, quality uPVC does the job well. Not sure which way to go? We'll give you a straight comparison for your exact opening — with prices for both
Cortizo Bi Fold Doors: Our Premium Aluminium System
For homeowners seeking premium style, performance and durability, our Cortizo bi-fold doors offer an exceptional solution. Their ultra-slim aluminium profiles maximise glass area, bringing more natural light and wider views into your home, while advanced thermal-break technology delivers U-values as low as 0.8 W/m²K. With PAS 24 security, flexible configurations from 2 to 14 panels, and options such as a convenient traffic door and level threshold, they are designed for modern everyday living. Panels can reach up to 1,200mm wide and 3,000mm tall, making them ideal for creating impressive floor-to-ceiling openings.
Why 4 Moon Windows?
Why Choose Aluminium Bi-Fold Doors in the UK Market Today?
When comparing aluminium bi-fold doors across the UK, you’ll notice that many suppliers simply quote from a catalogue and send a subcontractor. We work differently. At 4 Moon Windows, we take a hands-on approach from survey to installation.
Get Your Free Bifold Door Quote Today
Get Your Free Bifold Door Quote Today
Book your free consultation now — call, WhatsApp, or schedule a quick chat online. We'll measure up, talk through aluminium and uPVC options side by side, and give you a clear, no-obligation price.
FAQ
Frequently Asked Questions
Aluminium bifold doors offer slimmer frames, larger glass panels, more colour choices, and greater strength on wide openings. uPVC bifold doors cost less and insulate well on smaller spans. For openings over three metres or a premium finish, aluminium is usually the better investment; for tighter budgets and smaller openings, uPVC works well.
Prices depend on material, size, and panel count. uPVC bifold doors are typically the most affordable route, while aluminium systems like Cortizo cost more but last longer and achieve slimmer frames. We provide free, fixed quotes for your exact opening — with aluminium and uPVC priced side by side so you can compare.
Cortizo bi fold doors combine ultra-slim aluminium profiles with deep thermal breaks, achieving U-values as low as 0.8 W/m²K on the Bifold Plus system. They’re tested to PAS 24 security standards, support up to 14 panels, and offer traffic-door and level-threshold options for everyday practicality.
Most homes use between 2 and 7 panels, which suits openings from roughly 1.8 to 6 metres. Cortizo systems can extend up to 14 panels for very large apertures. An odd number of panels lets you include a traffic door — a single leaf that opens like a normal door for daily use.
Usually not. Replacing existing doors or fitting bifolds into a standard rear opening typically falls under Permitted Development. Larger structural openings may need Building Regulations approval for the lintel and safety glazing. We handle compliance and certification as part of every installation.
Yes. From our Thornton Heath base we cover Croydon and the whole of South London, including Bromley, Sutton, Mitcham, Streatham, and Wimbledon. Send us your postcode and we’ll confirm coverage and book a free survey.