What are bifold doors? Trade Bifolds UK answer some popular FAQs

What are bifold doors?

There are alternative names for Bifold Doors read our FAQs for Folding Sliding Doors or Folding Doors. No matter what they are called, opening up the bifold doors and folding the panels back against the wall really does let the outside into your home.

Allowing an unobstructed view into your garden or a step on to your balcony. Offering a quick and convenient way to relax, unwind and enjoy the view. Whilst giving your home a modern and contemporary look and style that you’ll love.

FAQ Technical Questions

How do you install a bifold door?

We have a guide on how to install your bifold doors. From the initial measuring stage and following the site survey through to the installation process.

What are the benefits of aluminium bifold doors

Aluminum is the most durable, long-standing and resistant material of those used for doors and windows. Aluminum has the strength, durability and low maintenance to last above other materials.

What is the energy value?

Maximum energy efficiency values: window transmittance from 1,5 (W/m2K)*.

*maximum tightness: CLASS 9A, which means during 55 minutes, total affluent of 330 litres and wind velocity of 114 km/h, there´s no water intake.


  • Air permeability – Class 4
  • Water tightness – Class 9A
  • Wind resistance – Class A3
Have the bifold doors been tested?

All our Cortizo’s enclosing systems are tested in the Test Laboratory at the Technological Center to guarantee the best performance in watertightness, air permeability and wind loads, endorsed by the maximum results in its test qualifications.

What configuration can I have?

The Cortizo range has a variety of compositions up to 14 sashes in outwards & inwards openings.

Which way do the doors open and slide?

Our bifold doors have inwards and outwards openings. They can be configured to open from the right or the left.
Please note what is to the left and right of the space and allow access to units when doors are open.

What does it mean by threshold?

Our low threshold frames can be used on balconies or for a seamless look. For areas that require a higher threshold choose the standard frame for a weathertight seal.

The Bi-fold system with Thermal break specially for enclosing large gaps. Allowing an inlay bottom frame leaving threshold completely accessible.

Are bifold doors PAS24 tested?

Latest test run by Cortizo.
Security test: Passed
Configuration 330. 2701 x 2517 mm / 3 sashes

Can the doors be trimmed?

No, our bifold doors are made-to-measure and are truly bespoke, therefore should not require trimming.

Do you provide trickle vents?

Yes, you can choose to have these installed during the bifold door designer process.

What type of glass is used?

We use standard and solar glass. These are double glazed units and have been tested to Class 4 Air Permeability when enclosed within the frame.

Are there any acoustic properties?

In order to transform the residence into a private space, intimate and free of pollution outdoor acoustics, Cortizo has designed its enclosing systems with all the latest technological developments necessary to ensure indoors peace and quiet.


FAQ common questions

How many doors can I have?

Cortizo frames can be constructed from 1 panel up to 14 panels. These can be in any configuration inwards or outwards. They can also be split with 7 panels on either side or run straight across from left to right or run right to left of the area.

Can I fit internal blinds?

Our safety or solar glass panels are double glazed and perfect for fitting internal blinds. We offer 4 internal blind colours these are Natural White, Silver, 7016 Grey and Black.

Can I choose any RAL colour bifold door?

We offer the entire RAL colour wheel chart in exclusive powder coating, metallic, textured, wood effect, more than 100 finishes are anodized. This electrochemical process gives the surface a decorative, durable, corrosion-resistant, anodic oxide finish.

We also offer aluminium on the outside and wood on the inside, two-coloured finishes… An unlimited offer to create a colour harmony at home.

Quality labels in every process: QUALICOAT, SEA-SIDE, QUALIDECO and QUALANOD.

FAQ Sales & Delivery

What is the lead time for my bifold doors?

The lead time for our bifold doors is 21 days.
Rooflights can be either collected or delivered. Lead time for delivery is 10 days.
Both options are from date of purchase.

Can I transfer my warranty?

Unfortunately the warranty is not transferable.
Trade Bifolds UK Ltd offers a 5 year parts only warranty on all our products with a 2 year glass warranty. This includes all profiles, hardware and accessories and is provided in conjunction with Trade Bifolds UK Ltd recommended guidelines on maintenance and installation.
Read more about our warranty installation guidlines.

What If I need to reschedule my order?

Please contact us as soon as possible so we can rearrange any new orders and deliveries.

Do I need to be present when the doors are delivered?

We are unable to deliver any of our products to another household due to the size, weight and nature of the product. In all instances we recommend the purchaser be present on site.

Try before you buy!

Finding the right bifold doors at the right price, to suit your home can be a difficult task. By offering our bifold doors to builders and homeowners, at trade prices we hope we’ve managed to take some of that hard work away.

By using our bifold door designer you can input your own specifications to fit your space. Making them truly bespoke.

Try me!
Bifold Designer for the homeowner and the trade.


Respect for the environment is CORTIZO’S commitment. Using innocuous raw materials and products in all our manufacturing process and the limitless possibility of aluminum recycling, allows us to remove any creation of waste and environmental risks.