Sleeper raised bed cut list calculator

How to use this calculator

Enter outside dimensions and the actual thickness across the wall, all in millimetres. Choose the corner arrangement in your design. Stock length means usable timber after any damaged ends are removed. Read each stock pattern as the pieces to cut from one sleeper; the adjacent count tells you how many sleepers use that pattern. The default 2,400 mm stock is an editable example, not a required size.

The formula

For length sides running through: length cuts = outside length; width cuts = outside width − 2 × wall thickness. Reverse the deduction when width sides run through. Each length needs 2 × beds × courses pieces. A stock pattern fits when total part lengths + (number of parts − 1) × kerf ≤ stock length. All feasible two-length patterns are compared to find the fewest stock sleepers for exactly the required pieces.

A worked example

For a 2,400 × 1,200 mm outside frame with 100 mm walls, two courses and length sides running through, cut four 2,400 mm sides and four 1,000 mm sides. From 2,400 mm stock with a 3 mm kerf, use four sleepers whole and cut two 1,000 mm pieces from each of two more. Total: six sleepers, 12 mm saw loss and 788 mm of leftover offcuts.

Assumptions & limitations

A rectangular frame with square butt joints, one unspliced piece per side, identical stock and the same corner arrangement on every course. Up to 12 bed-courses (48 total pieces). Offcuts can be shared across every bed and course. The exact minimum is for these stated cuts only: defects, end trimming, spare timber, fixings and any alternate-course design are excluded. A final trim removes up to one kerf from remaining scrap; a part ending exactly at the stock end needs no extra cut. This is a cutting list, not a structural or retaining-wall design.

Common questions

Will two 1,200 mm pieces fit a 2,400 mm sleeper?

Only if the cut removes no material. With a 3 mm kerf they need at least 2,403 mm of usable stock. Use a measured kerf, not just the saw blade body thickness.

Is the result a guaranteed minimum?

It is the exact minimum stock count for the two cut lengths and assumptions entered. It is not a promise about an unspecified construction layout, damaged timber or alternating corner arrangements.

How much soil fits inside?

Subtract twice the wall thickness from both outside dimensions, then use those inside dimensions and the intended fill depth in the raised-bed soil calculator.

Supporting reference

The method above states this calculator’s assumptions. This reference provides related definitions and technical context.

Wickes: raised sleeper bed construction and butt joints ↗

Formula and worked example checked against automated test cases. About our methodology.