What Are Accordion Doors? Folding Doors Explained

By
3 Minutes Read

If you have been researching folding doors, you have probably come across the term "accordion doors" and wondered whether they are the same as bifolds or something different. Accordion doors are a concertina-style folding door, and while they share the folding idea with bifolds, they are not quite the same thing. Here is the plain-English explanation of what they are and where they make sense.

We fit doors across York and North Yorkshire, so this guide sticks to what is genuinely useful rather than the marketing gloss.

What an accordion door actually is

An accordion door is made up of several narrow panels hinged together that fold back on themselves like the bellows of an accordion, hence the name. As you push or pull, the panels concertina into a compact stack, opening up the space. They run along a track and pleat together rather than swinging like an ordinary door.

You will see accordion doors used in two quite different ways:

  • Lightweight room dividers: slim, often vinyl or timber-panelled doors used indoors to separate rooms or close off an alcove. These are the classic "concertina door" many people picture.
  • Glazed folding doors: larger, framed and glazed versions used to open up a wall to the garden.

It is worth being clear which you mean, because they serve very different purposes.

Accordion doors versus bifold doors

This is the question everyone asks, so here is the honest comparison.

  • Panel width and stacking: true accordion doors tend to use lots of narrow panels that pleat tightly together. Bifold doors use fewer, wider panels (often around 600mm to 900mm each) that fold in pairs and stack neatly to one side.
  • Feel and quality: the word accordion often points to lighter, simpler concertina doors, while bifold usually means a substantial, glazed, weather-rated system designed to be a proper external wall.
  • Glass area: modern glazed bifolds give big, uninterrupted glass and slim frames. Concertina accordion doors have more frames and joins, so less clear glass.
  • Use: accordion doors are often internal dividers; glazed bifolds are typically the star external feature opening onto a patio.

In short, all bifolds fold, but not everything that folds is a bifold. If you want that wide, glazed opening onto the garden, what most people actually want is a bifold or sliding system rather than a lightweight accordion door.

Where accordion doors work well

Accordion doors earn their place in the right spots:

  • Tight spaces indoors: they take up very little room when folded, so they suit small openings, utility areas and dividing an open-plan space.
  • Occasional separation: handy where you want to close off a room now and then without a permanent wall or a swinging door eating into the floor.
  • Budget-friendly dividers: simpler concertina doors are an affordable way to add flexibility.

Where they are less ideal is as a main garden-facing opening, where you usually want more glass, better weather sealing and a more premium feel. For that, a glazed folding or sliding system is the better tool.

If it is the garden opening you want

If your real goal is to throw open a wall to the patio and flood a room with light, it is worth looking at proper glazed systems rather than a lightweight accordion door. Our aluminium sliding and bifold doors are built for exactly that: slim frames, large panes and weather sealing designed for the British climate. They fold or slide to create a wide opening while still locking up secure and keeping the heat in when closed.

For everyday external doors that are not about a full-width opening, a composite door or uPVC door is usually the sensible, secure choice.

Rough costs

Prices depend hugely on the type. A simple internal concertina divider is relatively cheap, often a few hundred pounds. A glazed external folding or sliding system is a bigger investment: as a rough 2026 guide, quality aluminium bifolds often fall somewhere between about 1,500 and 3,500 pounds per metre of opening, depending on specification, glass and finish. These are ballpark ranges only, and every opening differs, so get a quote for an accurate figure.

FAQs

Are accordion doors the same as bifold doors?

Not quite. Both fold, but accordion doors typically use many narrow panels that pleat together, and the term often refers to lighter internal dividers. Bifold doors use fewer, wider glazed panels and are usually a substantial external system.

Are accordion doors good for a patio or garden opening?

For a wide, glass-heavy opening onto the garden, a proper glazed bifold or sliding door is usually better, with more glass, stronger weather sealing and better security than a lightweight concertina door.

Do accordion doors save space?

Yes, that is their main strength. Because the panels fold flat against each other, they take up very little room when open, which makes them handy for tight internal openings.

Are folding doors secure?

Quality glazed folding and sliding systems come with multi-point locking and are secure. Lightweight internal accordion dividers are not designed as security doors, so they are best kept for internal use.

Thinking about opening up a room to the garden? Download our latest brochure to see folding and sliding options, or request a free quote and we will talk it through.

SM Windows & Doors

Author