Ottawa Closet Doors — Measurement Guide
How to measure a closet door opening.
Getting the right measurement is the single most important step in ordering replacement closet doors. It takes about five minutes with a tape measure and a level. Here is exactly how to do it.
What you need before you start
- Steel tape measure (not cloth)
- 4-foot level
- Pencil and notepad (or phone notes)
Remove existing door panels before measuring if possible — it is easier to get an accurate reading of the bare opening.
Measure the width — three times
Measure the inside width of the opening at the top, middle, and bottom. In most Ottawa homes, the opening will vary slightly between measurements — walls are rarely perfectly plumb.
Use the smallest of the three measurements as your working width. This is your door opening size. Do not use the largest measurement or you risk ordering panels that bind in the frame.
Write down all three measurements. If they differ by more than ¼ inch, the opening may need shimming or the frame may be racked — something worth noting before ordering.
Measure the height — top to floor
Measure from the finished floor surface to the underside of the head jamb (the horizontal piece at the very top of the opening). Do this in three places: left side, centre, and right side.
Again, use the smallest measurement as your working height. If there is carpet, measure to the top of the carpet — not the subfloor — since door clearance is calculated from the finished floor level.
Standard door heights in Ottawa homes are 80 inches (6'8"), but older homes often have 78-inch or non-standard openings. Do not assume; always measure.
Check if the floor is level
Place a 4-foot level on the floor across the opening. Note how much, if any, the bubble is off centre. Even a ¼-inch slope across 48 inches can affect how sliding bypass doors roll and stop.
For bypass doors, a level floor is important — panels glide on rollers, and a sloped floor causes them to drift to one side. This can be corrected during installation with track adjustment, but it is worth knowing in advance.
For bifold doors, a level floor matters less for operation but affects how the bottom pivot sits. Record the measurement so your installer can account for it.
Check the depth of the head jamb
Measure the front-to-back depth of the head jamb — the piece of wood the track will mount to. For bypass doors, you need a minimum of 1 inch of depth, ideally 1.5 inches, for the track to sit properly.
Many Ottawa homes have a standard 4½-inch jamb depth. If your opening has a very thin head casing or was previously trimmed down, measure carefully and note the dimension.
For barn doors, the track mounts on the wall above the opening — so head jamb depth is not a concern. What matters instead is whether there is solid backing (stud or blocking) where the track brackets will attach.
Check wall clearance for barn doors
If you are considering a barn door, measure the wall space to each side of the opening. You need clear wall equal to the door panel width — so a 36-inch panel needs 36 inches of unobstructed wall beside the opening.
Check for light switches, outlets, trim, and returns. Barn door track extends a few inches past the panel on both ends, so the clear wall requirement is slightly more than the panel width itself.
If clear wall is not available on one side, a pocket door or bypass system may be a better fit for your space.
Common measuring mistakes to avoid
Measuring the door panels instead of the opening
Old door panels are often smaller than the actual opening — especially if they were poorly fitted when installed. Always measure the rough opening or the inside of the door frame, not the existing panels.
Measuring only once
One measurement is never enough. Openings in Canadian homes — especially older Ottawa builds — are almost never perfectly square. Measure width and height in three locations each, every time.
Forgetting to account for carpet thickness
If there is carpet, measure to the top of it. Ordering a door sized to the subfloor will leave you with a door that binds on the carpet and cannot fully close.
Confusing rough opening with finished opening
The rough opening is the framed hole in the wall. The finished opening — inside the jamb — is smaller. We size panels to the finished opening. If in doubt, tell us whether you measured to the framing or to the finished jamb.
Not checking for obstructions above the opening
Track mounts to the head jamb. If there is a light fixture, sprinkler head, or ductwork near the opening top, it may interfere with track installation. Walk the space with a tape measure before ordering.
What to do with your measurements
Once you have your three width measurements, three height measurements, head jamb depth, and a note on floor level, you are ready to order. The numbers you send us are:
- Smallest width (your opening width)
- Smallest height (your opening height)
- Head jamb depth
- Door system type (bypass, bifold, barn)
- Finish preference
We do the panel sizing for you.
You send us the opening dimensions. We calculate the panel size, overlap allowance, and hardware clearances. You do not need to know how bypass panels overlap or how much bifold panels deduct — that is our job.
If your opening is non-standard or you are not confident in your measurements, we offer a paid in-home measure for Ottawa customers.
Ready to send us your measurements?
Use the full measurement guide or email us directly with your numbers. We will confirm door sizes and send a quote.