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Intermediate DIY · Doors

How to Install Bifold Doors

A pre-hung door is two things glued together: the door itself and the frame. The trick is that the frame has to land plumb, square, and level even if the rough opening isn't. Shims do the work.

Intermediate 2–3 hr

Bifold doors are space-saving closet doors that fold in on themselves rather than swinging out. They install on a track at the top, with a guide pin at the bottom corner. The job depends on getting the track straight and level, and aligning the doors so they don't drag when opening or closing. Common in closets and laundry areas.

This guide covers a standard 2-panel bifold (one panel each side) and 4-panel bifold (two pairs). Both follow similar installation principles.

Before you start

Three things to settle:

1. Door size to opening. Bifold doors come in standard sizes: 24, 30, 36, 48, 60, 72 inch widths. Height typically 80 inches. Match to your opening width — doors should fully cover the opening when folded back.

2. Track length matches opening. The track at the top of the opening must span the full opening width. Most track sets are cut to length during install. Verify track length is sufficient before opening the kit.

3. Pivot vs guide pins. Bifold doors have a pivot pin at the top and bottom of the leading edge (where doors fold), and guide pins on the trailing edge that ride in the track. Most doors come pre-drilled for both. Some units require the installer to drill pivot/guide holes — verify before starting.

What you'll need

Tools

  • Drill with bits
  • Screwdriver
  • Tape measure
  • Level (4-foot)
  • Hacksaw (for cutting track to length)
  • Step ladder

Materials

  • Bifold door kit (panels, track, hardware)
  • Wood screws #8 × 2 inch (for anchoring track)
  • Painter's tape (for marking)

Track must be perfectly level

Bifold doors slide along the top track. If the track is even slightly off-level, the doors will hit the floor unevenly during opening — one side drags, the other lifts.

Use a 4-foot level on the track during installation. Any visible bubble offset is too much. Adjust track shimming or remount until perfectly level.

Step-by-step instructions

Inspect the rough opening

Verify opening width matches door width spec. Standard rough opening is door width + 1/4 inch.

Check that the opening is plumb on both sides. Use a level on the door jambs (existing trim) — should be vertical.

Floor in the opening should be level. If not, plan for shimming.

Cut track to length

Measure the opening's inside width. Cut the track to this dimension with a hacksaw.

Smooth cut edges with a file.

Mount the track

Position the track inside the opening, against the top jamb (header).

Pre-drill 1/8 inch pilot holes at the track's mounting points (typically 4-6 holes per typical 36-inch track).

Drive #8 × 2 inch wood screws to anchor the track to the header. Screws should hit framing — drywall alone won't hold.

Verify track is level along its full length.

Install pivot brackets at the floor

Each pair of bifold doors has a pivot bracket on the floor at the leading edge corner (where the doors will fold).

Position each bracket per the kit's measurements — typically 1-1/2 inches from the side jamb.

Drive screws to anchor the bracket to the floor.

Install pivot pins on doors

If the doors come with pivot pins pre-installed, skip this step.

Otherwise, install pivot pins at the top and bottom of each door's leading edge (the edge that will fold). Drill the pre-marked holes if needed.

Install guide pins at the top of the trailing edge (the edge that slides in the track).

Hang the doors

Lift the first door (or pair) into position. Insert the top pivot pin into the track's pivot socket; insert the bottom pivot pin into the floor bracket.

Insert the guide pin at the top into the track.

Test the fold — doors should swing freely on the pivots and slide smoothly along the track.

Adjust pivot height

Most bifold pivot pins are threaded — turn to adjust height of the door.

Adjust until the door's bottom edge clears the floor by 1/4 to 1/2 inch and the door is parallel to the side jamb.

Lock with the small set screw on the pivot pin.

Install door knobs and aligners

Most bifold doors have a knob or pull on the leading edge of each pair (where you grip to fold).

Some installations also include door aligners — small spring-loaded clips that hold the doors closed and aligned.

Install per kit instructions.

Final adjustment and test

Open and close the doors several times. Watch for: dragging on the floor, binding in the track, doors not aligning when closed.

Adjust pivot height or track position as needed.

Properly installed bifold doors should fold and unfold smoothly with one-handed operation.

Common mistakes that cost you

Frequently asked questions

Can I install bifold doors in any opening?

Most rough openings work, but some require modification. Standard openings: 24-72 inches wide.

Very narrow openings (under 24 inches) can use single bifold doors. Very wide openings (over 96 inches) typically use sliding doors instead.

Why do my bifold doors keep falling off?

Most common: pivot pin not fully seated in the track or floor bracket. Re-seat firmly.

Less common: bracket pulled free of the framing. Re-anchor with longer screws.

Should I paint bifold doors before or after installing?

Before is much easier. Paint flat, with all six surfaces accessible.

After install, painting requires masking the track and floor, working around the hardware.

When to call us instead

If you're updating doors throughout a renovation, professional installation ensures consistent quality across all doors. We handle door installation as part of larger renovation work.

Book a free 60-minute site visit →

Related Ottawa services

If you're updating closet doors and trim throughout a home, our residential renovation team handles door installation as part of fixed-price scopes. Book a free 60-minute consultation.