Architrave calculator: lengths and cut list
The calculator needs JavaScript. The worked example, formula and figures below show exactly how it works, so you can do the sum yourself. A guide, not advice. Check your supplier's or maker's figures before ordering.
Short answer
Worked example
| You enter | Value |
|---|---|
| Doors | Internal doors: opening width 762 mm, opening height 1,981 mm, how many doors this size 3 |
| Faces | Both sides |
| Lengths you can buy | 2.1 m |
| Allowance per piece | 100 mm |
Order: 15 × 2.1 m lengths of architrave
| Result | Value |
|---|---|
| Lengths to buy | 15 |
| Length to buy | 2.1 m |
| Legs | 12 |
| Heads | 6 |
| Architrave fitted | 28.34 m |
| Left over | 3.16 m |
| Mitre cuts | 24 |
| Length | Cut into | Offcut |
|---|---|---|
| 1 (2.1 m) | Internal doors 1, face 1: left leg: 2.081 m | 0.019 m |
| 2 (2.1 m) | Internal doors 1, face 1: right leg: 2.081 m | 0.019 m |
| 3 (2.1 m) | Internal doors 1, face 2: left leg: 2.081 m | 0.019 m |
| 4 (2.1 m) | Internal doors 1, face 2: right leg: 2.081 m | 0.019 m |
| 5 (2.1 m) | Internal doors 2, face 1: left leg: 2.081 m | 0.019 m |
| 6 (2.1 m) | Internal doors 2, face 1: right leg: 2.081 m | 0.019 m |
| 7 (2.1 m) | Internal doors 2, face 2: left leg: 2.081 m | 0.019 m |
| 8 (2.1 m) | Internal doors 2, face 2: right leg: 2.081 m | 0.019 m |
| 9 (2.1 m) | Internal doors 3, face 1: left leg: 2.081 m | 0.019 m |
| 10 (2.1 m) | Internal doors 3, face 1: right leg: 2.081 m | 0.019 m |
| 11 (2.1 m) | Internal doors 3, face 2: left leg: 2.081 m | 0.019 m |
| 12 (2.1 m) | Internal doors 3, face 2: right leg: 2.081 m | 0.019 m |
| 13 (2.1 m) | Internal doors 1, face 1: head: 0.862 m; Internal doors 1, face 2: head: 0.862 m | 0.376 m |
| 14 (2.1 m) | Internal doors 2, face 1: head: 0.862 m; Internal doors 2, face 2: head: 0.862 m | 0.376 m |
| 15 (2.1 m) | Internal doors 3, face 1: head: 0.862 m; Internal doors 3, face 2: head: 0.862 m | 0.376 m |
Show the working
- Internal doors: 3 × 2 faces: legs 1,981 = 1,981 mm, head 762 = 762 mm
- 12 legs and 6 heads, each + 100 mm, packed into 2.1 m lengths: 15 lengths (31.5 m bought, 28.34 m fitted)
- Mitre cuts: 12 leg tops + 2 × 6 heads = 24
How it works
- Per door face: 2 legs (opening height + architrave width) and 1 head (opening width + 2 × architrave width)
- Each piece gets the allowance per piece for squaring and mitring
- Pieces are packed into stock lengths longest first (first-fit decreasing), keeping the stock length that buys the fewest metres
- Mitre cuts = 4 per face (2 at the top of the legs, 2 on the head)
Heads are short, so two often come out of one length: the cut list shows which.
Our default (adjustable)
These are typical planning figures and our own allowances, not facts about your product. Change any of them in the calculator to match your bag, pack or tin.
| Figure | Our default (adjustable) | Kind | Source |
|---|---|---|---|
| Lengths you can buy | 2.1 m | Common UK size Not yet checked against the source | From your product brief v2 AR1 (2.1 m stock). Researcher to add the other lengths merchants sell. |
| Allowance per piece | 0.1 m | Our assumption Not yet checked against the source | Our choice: change it to suit your job Allowance per piece for squaring ends and mitres (brief v2 FL2). |