How to fit an internal bi-fold door
In small rooms where every inch of space counts, bi-folding doors are a great choice to make the most of your home. They can be tucked neatly out the way when open, and easily pulled across to create new areas like home offices or play rooms.
Internal bi-fold doors open in a much smaller area than regular doors, so they are a perfect option if you’re short of space and ideal for closets, cupboards, bathrooms and hallways.
For this project, we’re installing a single bi-fold door kit into an existing doorframe. The doors can be fitted so they fold either to the left or the right, and we will demonstrate fitting a left-hand fold door, as well as tips on fitting a right-hand fold door.
In this guide, we’ll show you how to:
- Measure the doorframe opening correctly to work out what size bi-fold door you need
- Fit the top track and bottom pivot
- Install the bi-fold door
- Make adjustments to the alignment
- Add a door knob
Before you start
The process for fitting each bi-fold door will vary depending on the manufacturer and the size of the door, so always read and follow any specific product instructions, supplied with the door, before you start.
If you’ve not yet chosen which bi-fold door to go for, now’s the time to make your decision. Our wide range of internal bi-fold doors will give you plenty of inspiration.
Measure your space
Before choosing your bi-fold door, reach for your tape measure and see what size door you need. Bi-fold doors are manufactured to fit into a variety of standard door opening sizes. Measure the door opening to make sure you’re buying the right size bi-fold door for the opening.
How wide?
First, measure the top, middle and bottom of the frame opening where the door will go. Use the widest measurement to find the width of your new bi-fold door.
How high?
Measure the height within the frame opening at two points – vertically on the left and right sides. The longest length will tell you the height you require.
Once you've taken your measurements, compare them with the sizes available in the style you like. Bi-fold doors are made smaller than the doorframe to allow for the track and fittings and the doors are made to fit a variety of standard opening sizes. Because of their construction, bi-fold doors can’t be trimmed to fit the opening.
Safety first
- Always wear safety goggles when drilling above your head
- Use a step ladder when working at height
You will need
- Tape measure
- Pencil
- Drill driver with 2mm and 5mm wood drill bits
- Screwdriver – electric or manual, or opt for a drill driver
- Rubber mallet
- Step ladder
- Bi-fold doors, including track and fixings
- Door knob
- Safety goggles when drilling
Fixings & fittings
Before you begin to fit your chosen door, check you have all the fixings and fittings required - all the parts will be included with your bi-fold door kit.
The top track is usually attached to the door in its packaging, and you will need to remove this with a screwdriver before fitting.
In this guide, we will demonstrate how to fit a left-hand side door, and the pivot bracket will be positioned on the left side of the door frame. This will be on the opposite side if a right-hand opening door is required.
Installing your door
Step 1
The top track needs to be positioned 19mm back from the front edge of the doorframe. Measure and mark this position with a pencil on both the left and right sides of the frame.
For this project, we need to position the track with the track bracket’s pivot hole to the left, and this will be on the opposite side of the frame if a right-hand fold door is required.
Step 2
Position the track onto and behind the marked line and ensure it is level and central within the doorframe.
Use the screw holes to mark their position onto the doorframe, before removing the track and drilling pilot holes with a 2mm wood drill bit. Don’t forget to wear safety goggles to protect your eyes from falling wood dust when drilling.
Screw the track into position, using the screws provided.
Step 3
Measure and mark the bottom pivot bracket position, for this door it’s 1980mm from the top of the track, down the frame on the hanging side.
Measure and mark 19mm in from the inside edge of the frame onto the marked line.
Step 4
The intersecting mark indicates the bottom left position of the bottom pivot bracket, or bottom right position for a right-hand door.
Position the bracket and mark the screw positions onto the doorframe with a pencil, drill pilot holes with a 2mm drill bit and secure the bracket to the frame by screwing it into place with the three 35mm screws provided.
Slot the plastic pivot retainer into the bottom pivot bracket. For this door, the bracket will be ‘floating’ above the floor, and there’s no need to fix it to the floor.
Step 5
Fold the door at 90 degrees and stand it up in the opening to help identify where the top pin pivot and the roller guide pivot is positioned in the top of the door. Slot the fixings loosely into the pre-drilled holes. Do the same for the serrated bottom pivot too.
Return the door to the floor and, using a rubber mallet, carefully tap in the three pivots into their holes.
Step 6
Next we are ready to install the door, it’s a good idea to have someone help hold the door in position whilst the pins and pivots are engaged.
First, unscrew and release the top pivot within the track.
Offer the door back up to the opening and engage the top pin pivot into the pin pivot hole.
Engage the roller guide into the track and, whilst supporting the door, check it slides freely in the top track.
Slot the bottom pivot into the bottom pivot bracket, being careful you do not trap your fingers between the door and the frame. Check the door slides freely along the track.
Adjust the top pivot in the track and set the correct gap between the door and the frame. Ensure the door opens correctly before tightening the screw in place. Align the bottom pivot by sliding it left or right to create a uniformed gap.
Top Tip
Vertical adjustments can be made by lift the door slightly out of the bottom bracket and screwing the bottom pivot up or down. It’s clockwise to raise the door or counter-clockwise to lower the door.
Step 7
Clip the spring closer unit into the track at the closing end where it will operate between the doorframe and the pivot roller, this will grip the door closed and will also soften the door closing operation.
To help achieve a smoother close, two different spring sizes are supplied with the bi-fold door.
Step 8
A door knob can be fitted to the opening side for left or right-hand locations, and the ideal height is about 900mm up. Measure and mark the location with a tape measure and pencil onto the front of the door.
If your door is supplied with a door handle, the handle is usually fixed on with a bolt from the other side. Drill a hole into the door at the marked position all the way through to the other side. The supplied door knobs require a 5mm wood drill bit.
Open the door and screw the knob into place whilst holding the nut on the back of the door. For decorative purposes, you could also add a matching door knob to the other door.
How to align two sets of bi-fold doors
If you have a wide door way and installing two bi-fold doors together, you’ll need to fit aligner brackets to create a smooth and aligned closing where the two doors meet. An aligner bracket and two screws are supplied with each bi-fold door, and these brackets are only required when two sets of doors are fitted together. Once fitted, they simply dovetail together when the two pairs of doors are closed.
Step 1
To fit the liner brackets, close the doors, and from the inside, mark a 4cm pencil line about 200mm up from the bottom of the door, across both the doors where they meet.
If you can’t do this from the inside when the doors are closed, remove the doors to fit the brackets.
Step 2
Position the first aligner on the line as shown and mark the two fixing holes. Drill a couple of pilot holes with a 2mm drill bit, being careful not to drill all the way through the door. Repeat for the other door.
Screw an aligner bracket to each door. Test the fit and adjust as necessary.