Fitting a sliding door: which type suits your house?

Fitting a sliding door gives your living room or extension a wide opening to the garden, without a door swinging inwards. You choose between a standard sliding door, a lift and slide door and a bifold door, in uPVC, timber or aluminium. In an existing facade there is more building work involved than just the frame: the opening is often widened and a new lintel is needed. In a new extension the glazed door is included in the design straight away. Below we set out the choices and the points to watch.

What types of sliding doors are there?

With a sliding door, one part slides along a fixed part. With a lift and slide door, the handle first lifts the sash slightly, so it runs lightly and seals well when closed. A bifold door folds aside like an accordion and clears almost the whole opening.

Which type suits you depends on the width of the opening, how often you open it and how much space there is inside and outside. A bifold, for example, needs room for the folded panels, a sliding door does not. If in doubt, it helps to see and operate one in real life.

• Sliding door: simple and often the most affordable choice
• Lift and slide: runs lightly and seals well, even when large
• Bifold door: almost the full width open in summer
• French doors: a classic alternative for a narrower opening

uPVC, timber or aluminium?

uPVC is low maintenance and insulates well. Timber suits a traditional house and is easy to repair, but needs periodic painting. Aluminium allows slim profiles and therefore a lot of glass.

Which material suits you depends on the style of the house and your wishes regarding maintenance. A detailed comparison can be found in timber or uPVC window frames. We fit all three, as part of our window and door frames service.

What is involved in fitting a sliding door in an existing facade?

The new opening is often wider than the old frame. The brickwork above is then temporarily supported and a new lintel is installed, usually steel or concrete. A structural engineer determines the size. Broadly it works the same as removing a load-bearing wall.

Then come fixing the frame, the damp-proof tray under the threshold and the finishing inside and out. A good connection to the cavity prevents cold and damp around the edges.

What should you watch with a sliding door in an extension?

In a new extension the glazed door can be designed to size, including the lintel above it. Think early about the threshold: a recessed or level threshold gives a smooth transition to the patio, but needs good drainage outside.

If you combine the doors with a roof lantern, the room gets light from two sides. For that, read an extension with a roof lantern.

What about insulation and security?

A sliding door is a large area of glass, so the insulation value of the glass and profile makes a difference. HR++ double glazing is standard, triple glazing insulates better. Also look for good hardware with multi-point locking and burglar-resistant glazing where needed.

Ask about the burglar resistance of the complete frame, not just the lock. A strong lock in a weak profile does not help much.

Frequently asked questions