Manual · 02
How to measure a wall, a room, doors and windows
How to measure a wall, a room, doors, windows and a bathroom, with drawings.
Good numbers come from good measurements. Every tool asks for sizes, and the rules are the same everywhere: measure to the finished surface, write the number down, and check it once.
What to measure with
- Tape measure: hook it on one side, read it on the other. For a long wall, ask someone to hold the end.
- Laser measure: put it flat against one wall and aim at the other. The quickest way to measure a room.
- Phone Measure app: good for a first idea. Check with a tape before you order anything cut to size.
Measuring a wall
- Measure the whole wall. Roomveil takes the windows and doors off for you when you add them.
- If the ceiling slopes or the floor is uneven, measure at the highest point.
Measuring a room
Measuring doors and windows
There are three different things you might measure, and each one gives a different size to order. In the doors and windows tool, every door and window asks What did you measure? so it can work out the right size.
| What you measured | What Roomveil tells you to order |
|---|---|
| The old door slab, edge to edge | The same size. Standard widths are 24, 28, 30, 32, 34 and 36 inches, usually 80 inches tall (96 inches for tall doors). |
| The rough opening (framed hole, stud to stud) for a door | About 2 inches less wide and 2½ inches less tall. A 32 × 80 inch door needs a 34 × 82½ inch opening. |
| The rough opening for a new-construction window | About ½ inch less each way. |
| Inside the old window frame (replacement window) | The smallest of your three measurements, less about ¼ inch each way. |
Measuring a bathroom
Measure the floor wall to wall, across and front to back. Then measure where the pipes come out: the toilet drain is usually 12 inches from the wall behind it (this is called the rough-in).
Updated 2026-10-01