How Much Wainscoting Do I Need? Boards, Planks and Cap Rail
Wainscoting covers the lower third of a wall in boards, with a cap rail along the top. 34 ft of wall (after the doors) at 36 inches high takes 82 board pieces of 5.5 inches, or 41 planks of 8 ft, with 34 ft of cap rail. The wainscoting calculator counts it for your walls.
Boards by length of wall
For wainscoting 36 inches high in 5.5 inch boards from 8 ft planks, with one door of 3 ft left out and 10% extra:
| Wall length | Board pieces | Planks of 8 ft | Cap rail | Cap rail pieces of 8 ft |
|---|---|---|---|---|
| 20 ft | 41 | 21 | 17 ft | 3 |
| 30 ft | 65 | 33 | 27 ft | 4 |
| 40 ft | 89 | 45 | 37 ft | 5 |
| 50 ft | 113 | 57 | 47 ft | 7 |
| 60 ft | 137 | 69 | 57 ft | 8 |
| 80 ft | 185 | 93 | 77 ft | 11 |
Planks by height
For 34 ft of wall in 8 ft planks:
| Height | Pieces from a plank | Planks to buy | Wall area covered |
|---|---|---|---|
| 32 in | 3 | 28 | 91 sq ft |
| 36 in | 2 | 41 | 102 sq ft |
| 42 in | 2 | 41 | 119 sq ft |
| 48 in | 2 | 41 | 136 sq ft |
| 54 in | 1 | 82 | 153 sq ft |
Choose a height that cuts the plank with little waste: 32 or 48 inches use the whole plank.
Choosing the style
- Beadboard. Narrow tongue and groove boards with a bead. A traditional look that suits kitchens, baths and halls.
- Shiplap. Wider boards with a small gap or a rabbet. A clean farmhouse look.
- Board and batten. Flat boards with narrow strips over the joints: see the board and batten calculator.
- Panels. Sheets of 4 by 8 ft that are cut to height. Fast to fit, and cheaper than boards.
Fitting it
- Mark a level line at the height all round the room, since floors and ceilings are rarely level.
- Find the studs and nail the boards into them, with construction adhesive on the back as well.
- Cut round the outlets and switches before you fix each board, and use box extenders so they sit flush.
- Fit the baseboard at the bottom and the cap rail at the top, and fill the nail holes and joints before painting.
- Leave a small gap at the corners for the wood to move, and cover it with caulk.
See also the baseboard trim calculator and the crown molding calculator. These are estimates: measure your own walls and openings.
Frequently asked questions
How much wainscoting do I need?
The wall length less the doors, divided by the width a board covers: 34 ft of wall in 5.5 inch boards takes 82 pieces, or 41 planks of 8 ft.
How high should wainscoting be?
About a third of the wall: 32 to 36 inches with 8 ft ceilings. 36 inches suits a standard 8 ft plank, with two pieces from each.
How much cap rail do I need?
The same as the length of wall covered: 34 ft, or 5 pieces of 8 ft.
How many pieces do I get from a plank?
Two pieces of 36 inches from an 8 ft plank, and only one if the wainscoting is higher than 48 inches.
Do I include doors and windows?
Take off the width of each door and opening at floor level. Windows that sit above the wainscoting do not change the length.
More guides
Tools & materials for this project
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Estimates only. Quantities depend on your materials, site and supplier. Confirm important numbers before you order, and follow local building codes for anything structural.