Bifold Doors vs Sliding Doors: Which Is Right for Your Home?

Bifold doors and sliding doors are the two most popular ways to open up the rear of a home and connect inside to garden. Both are stunning in aluminium, both flood a room with light — but they behave very differently. This guide compares them honestly on the things that actually matter when you are spending several thousand pounds: opening width, sightlines, glass area, cost and day-to-day living.

How they open

Bifold doors fold back in a concertina of panels that stack neatly to one or both sides, opening up almost the entire aperture — typically 90% or more of the width. Sliding doors glide one pane behind another, so the maximum opening is usually around half the total width (with a two-pane set) but you keep larger, uninterrupted panes of glass when the doors are closed.

If your priority is throwing the whole wall open on a summer afternoon, bifolds win. If you spend more time looking through the glass than walking through it — and want the cleanest possible view of the garden in winter — sliding doors are hard to beat.

Sightlines and glass area

Sightlines are the width of the aluminium frame you see between panes. Sliding doors have fewer vertical frames, so they give larger panes and a more minimal look — modern slimline systems like the Schüco ASS 50 or Cortizo Cor Vision have sightlines as narrow as 20–35mm. Bifolds have a frame at every fold, so you see more aluminium, but the trade-off is that those frames disappear entirely when the doors are open.

Cost compared

For similar sizes the cost is broadly comparable, and the door type alone is rarely the deciding factor — panel count, glass specification, system and finish matter more. As a guide, a mid-range aluminium bifold or sliding set for a typical rear extension lands somewhere between £3,000 and £6,500 supplied and fitted. See our bifold door cost guide for a full price breakdown by panel count.

Which should you choose?

• Choose bifold doors if: you want to open up the full width, you have the wall space for panels to stack, and you love the indoor-outdoor flow in summer
• Choose sliding doors if: you want the biggest, clearest panes of glass year-round, the most minimal frames, and a flush threshold with effortless operation
• Consider both: many homeowners fit bifolds on the main garden aperture and a sliding door or window elsewhere — aluminium lets you mix systems with a matching finish

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