What size are new sleepers?

New green-treated softwood: typically 2.4m x 200mm x 100mm. Reclaimed oak (hardwood): 2.6m x 250mm x 150mm — the size most UK reclaim merchants now stock (older mainline oak was 125mm thick). Set the actual length you are buying under Advanced Options if it differs.

How do I fix sleepers?

Use coach screws (200mm+), threaded rod, or metal brackets. Pre-drill to prevent splitting.

Are old sleepers safe for veg beds?

Old creosote-treated sleepers should not be used for food growing. Use new untreated or pressure-treated sleepers.

Are railway sleepers safe for raised beds?

New untreated or green-treated softwood sleepers are safe. Old railway sleepers may contain creosote (a carcinogen) and should not be used for vegetable beds.

How do I join sleepers together?

Use long timber screws (200mm+), coach bolts, or rebar driven through drilled holes into the ground. Stack them in a brickwork pattern for extra strength.

GardenCalcs

Sleeper Calculator — Railway Sleepers for Gardens

Work out how many railway sleepers you need for raised beds or retaining walls.

Bed Length

Outside length of the longer side. Each long side is cut from its own sleeper, so a 3.6m side needs two 2.4m sleepers.

Bed Width

Outside width of the shorter side. A bed up to 2.4m wide takes one sleeper per side; wider beds round up to two.

Courses High

Number of stacked rows. One course (200mm) suits edging; two (400mm) is typical for veg beds; three or more for retaining walls.

How We Calculate This

Sleepers per course = Ceil(Length ÷ Sleeper Length) × 2 + Ceil(Width ÷ Sleeper Length) × 2. Total sleepers = Per course × Courses. Each side is cut from its own whole sleeper (the standard buying convention), so changing the Sleeper Length in Advanced Options feeds straight into the formula.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates based on standard gardening guidelines. Results may vary with soil conditions, climate, and plant varieties.