Plan equal wall moulding frames, check the clear inside size and see how complete sides fit into stock lengths. Get a cutting list, spare stock, pack quantities and optional cost.
How much moulding do I need for wall frames?
Each rectangular wall frame needs two horizontal pieces and two vertical pieces. If its outside width is W and outside height is H, the total finished length is 2 × (W + H). Multiply by the number of identical frames. Then plan how those complete pieces fit into the stock lengths you can buy.
This wall moulding calculator handles both steps. It can divide a wall zone into equal picture frame moulding panels, or use a frame size you already know. It produces outside dimensions, clear inside dimensions, a square-blank cut list, whole stock quantities, spare lengths and optional cost. The same rectangular trim detail is often called picture frame molding or wall panel moulding.
Measure the wall zone and choose the spacing
Measure the actual area available for the frames. If they sit above a skirting board and below a cornice, use the space between those boundaries. Enter left, right, top and bottom margins within that zone. Horizontal and vertical gaps are clear distances between the outside edges of neighbouring frames.
For equal frames across a row, outside frame width = (wall-zone width − left margin − right margin − horizontal gap × (columns − 1)) ÷ columns. Use the same formula vertically with height, top and bottom margins, vertical gaps and rows.
For example, a 360 cm wide zone with 30 cm margins and three columns separated by 15 cm gaps gives (360 − 30 − 30 − 2 × 15) ÷ 3 = 90 cm outside width. A 240 cm high zone with 30 cm above and below gives 180 cm outside height for one row.
Mark the proposed frames on the wall before buying. Check switches, sockets, furniture, radiators, windows and door trim. Subtracting a window's area does not solve a frame layout around it. Split an interrupted wall into separate zones or draw a custom layout.
Outside size, inside size and the long point
The dimensions in this calculator refer to the outside rectangle. At a 45° mitre, measure each finished piece between its two long points. The profile face width is the visible width of the moulding when it lies flat on the wall. It is not the profile's projection away from the wall.
Clear inside width = outside width − 2 × profile face width. Clear inside height uses the same subtraction. A 90 × 180 cm frame made with a 3 cm wide profile has an 84 × 174 cm clear opening. If you start with a required inside opening, add twice the profile width to each dimension before using the known-frame mode.
The model assumes four straight sides forming a square-cornered rectangle. Two 45° cuts meet at each 90° corner. It does not calculate compound crown cuts, wall returns, curved profiles, decorative corner blocks or repeating profile motifs.
Why the cutting list uses square blanks
The plan first divides stock into square-ended blanks. Each blank is longer than its required finished side by your finishing allowance at both ends. You then make the two 45° mitres within that blank, keeping the required long-point length. This gives a clear way to budget material without assuming shared mitre cuts or nested wedges.
- Blank length = finished outside length + 2 × finishing allowance per end.
- Stock consumed for one blank = blank length + square-crosscut kerf.
- Usable stock = purchased stock length − 2 × stock-end trim.
Kerf is the width of material removed by the saw cut. Enter the actual allowance for a square crosscut. The tool reserves one such cut for every blank, including the last blank on a stock length. The extra material removed when forming the mitres is already contained within the blank envelope, so it is not added again as a second kerf budget.
Finishing allowance is extra length for trimming the blank to its final long points. It is not the profile face width. The starting values of 1 cm per blank end, 0.3 cm crosscut kerf and 0.5 cm per stock end are editable examples. Check your material, tool, end condition and working method. A direct mitre-cutting workflow can use material differently and needs its own verified cut sequence.
Example: three 90 × 180 cm wall frames
Use the 360 × 240 cm wall zone and spacing described above. Three frames need six horizontal sides at 90 cm and six vertical sides at 180 cm. Their finished long-point lengths total 1,620 cm, or 16.2 m.
With 1 cm of finishing allowance at each end, the square blanks are 92 cm and 182 cm. Add a 0.3 cm crosscut kerf to each blank. A 240 cm stock length with 0.5 cm trimmed from both ends has 239 cm available.
- A vertical blank consumes 182.3 cm. A horizontal blank will not fit beside it.
- Six stock lengths are therefore needed for the six vertical blanks.
- Two horizontal blanks consume 184.6 cm. The six horizontal blanks use three more stock lengths.
- The cut plan needs nine stock lengths. A 10% reserve rounds up to one additional whole length.
- With no owned stock and single-length packs, buy ten lengths of 240 cm, totalling 24 m.
At an illustrative price of €8 per length, the moulding cost is €80. The example button fills these values. Dividing 16.2 m by 2.4 m and rounding to seven lengths would leave the project short because it ignores how whole sides fit.
Stock length can change the result. With 300 cm stock and the same allowances, one vertical and one horizontal blank fit together. The plan uses six lengths, plus one spare at 10%. Compare actual prices and availability before choosing a length.
Spare stock, packs and material already owned
Spare stock is calculated as a percentage of the number of lengths used by the cut plan, rounded up to a whole length. It is separate from the trimming and kerf allowances. Enter zero if you want no additional spare lengths. The 10% starting value is a planning choice, not a requirement for every product.
Only count owned stock that is a complete usable length of the same profile and entered length. Short offcuts cannot be entered as whole stock. The tool subtracts owned lengths from the cut plan plus spares, then rounds the remainder up to complete packs. Pack rounding may leave extra lengths beyond the selected reserve.
Enter a price for one complete pack. For individually sold lengths, set one length per pack and enter the price of one length. The estimate covers new moulding only. Adhesive, fixing materials, filler, finish and delivery are separate.
Before cutting and fixing
Check the chosen manufacturer's instructions for the profile, substrate, adhesive and cutting method. Orac's wall-moulding installation guide includes layout marking, angle checks and mitring steps. These checks matter because a mathematical rectangle does not verify the actual wall or installation.
Make a trial corner or frame before cutting the whole batch. Keep the profile orientation consistent, check the long points and dry-fit the corners. Follow your tool's instructions and use an appropriate method for securing the material. The displayed stock bars show allocation, not blade position or a machine cutting program.
Frequently asked questions
Does this find the absolute minimum amount of moulding?
No. It sorts the required blanks from longest to shortest and places each into the tightest available space that fits. This produces a valid practical allocation, but it does not prove a global minimum. Compare other stock lengths and review the cut list before ordering.
Can I use inches or feet?
Yes. Choose centimetres, millimetres, metres, inches or decimal feet. Changing units converts every dimension, including the allowances. Fractional values are retained in the calculation. Results display up to three decimal places, so mark precise repeating dimensions from a measured layout rather than repeatedly adding rounded screen values.
Can frames be different sizes?
This calculation uses identical frames. Calculate each size separately, then review the combined cutting list if you want to share remaining stock between sizes. Simply adding separate purchase quantities can overestimate a combined order. The tool does not optimise mixed frame sizes in one run.
Can I join two short offcuts to make one side?
No joins are included. Every side must fit as one complete blank. If it is too long, the calculator asks for longer stock or a changed design. A scarf joint or another joining method needs a separate construction and allowance plan.
What about paint or wallpaper inside the frames?
Use the clear inside dimensions when planning the visible area. Wallpaper cutting, pattern repeat and paint coverage need their own allowances. Use the wallpaper calculator for roll planning. Confirm the profile overlap and your finishing method before ordering a precisely sized decorative insert.
