Wall Panelling Calculator
Plan wainscoting or box (picture-frame) moulding on a wall. Enter the wall size and get equal panel sizes, the moulding length and sticks to buy, a to-scale blueprint, a marking guide and a cut list.
Advanced
What this calculator does
It lays out wall panelling (wainscoting) made from box or picture-frame moulding: equal boxes in a grid, with the same spacing at the sides, between boxes and between rows. A dado or chair rail can separate a lower and an upper zone. All sizes are to the outer edge of the moulding.
How to use it
Enter the wall width and height, choose 1–3 rows and leave columns blank for Auto. The dado rail height is measured from the floor to the top of the rail. Open Advanced to set the rail strip, skirting (baseboard), cornice (crown moulding) drop, target box width, stick length and waste. Use the blueprint toggles for dimensions, marking lines and labels, then print or download the drawing.
Formulas
columns = round((W − s) ÷ (target + s)); box width = (W − (columns + 1) × s) ÷ columnslower height = (rail top − strip − skirting) − 2s; upper height (2 rows) = (H − cornice − rail top) − 2smoulding = Σ 2 × (width + height); sticks = ceil(moulding × (1 + waste) ÷ stick length)
Worked example
A 4040 × 2125 mm wall with 2 rows, 100 mm spacing and the rail top at 800 mm gives 4 columns of 885 mm. The lower boxes are 885 × 568 mm and the upper boxes 885 × 1125 mm. That is 8 boxes, 27.7 m of moulding, 13 sticks of 2.4 m with 10% waste, 2 rail sticks and 32 mitre cuts.
Frequently asked questions
What is the difference between wall panelling and wainscoting?
Wainscoting is wall panelling on the lower part of a wall, usually below a dado or chair rail. Box or picture-frame moulding is the common way to build it: rectangular frames fixed to a flat wall.
Are the sizes to the inside or outside of the moulding?
To the outer edge of the moulding. Each box's moulding length is its perimeter, and each corner is a 45° mitre cut.
How is the dado rail height measured?
From the floor to the top of the rail. The rail strip height is subtracted to find where the lower boxes end.
Do skirting and cornice change the layout?
Yes. Skirting (baseboard) raises the bottom of the lower boxes and a cornice (crown moulding) drop lowers the top of the upper boxes, so the boxes get shorter.
How much waste should I allow for mitre cuts?
10% is a common allowance. Increase it if your sticks are short or you expect to miscut, because every box side needs two mitres.
What if a box side is longer than one stick?
The calculator warns that the side needs joining. Join pieces with a scarf or butt joint at a stud and fill the seam.