Garden & outdoor

How much wood and roofing for a garden tool shed?

Floor, wall and roof m² plus plywood sheets and foundation blocks for a DIY wooden garden tool shed from length, width and height.

Quick answer

A small wooden tool shed is three surfaces: **floor**, **walls**, and **roof**. A **2 × 1.5 × 2.1 m** lean-to often needs about **3 m² floor**, **~15 m² walls** (minus the door), and **~3.5–4 m² roof** once pitch and overhang are included — then convert to **standard 122×244 cm sheets** with spare for cuts.

Advanced settings

Wall cladding

12.9 m²

Floor area
3 m²
Roof covering
3.4 m²
≈ 122×244 cm sheets
8
Corner + intermediate posts
4
Foundation pier blocks
6
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Walls = perimeter × height − door (~1.8 m²). Roof = floor × roof factor (lean-to ~1.12, pitched ~1.25) for pitch/overhang. Sheets = (floor + walls + roof) × (1 + waste) ÷ 2.98 m². Posts: 4 corners + extras every ~1.2 m on long sides. Pier blocks ≈ every 1 m along both long sides. DIY estimate only — not a structural or planning certificate.

How it works

Enter length, width and wall height. Pick flat/lean-to or pitched roof. The calculator returns cladding areas, sheet count, corner/intermediate posts and concrete pier blocks for a simple raised base. Check local planning rules and wind/snow loads — this is a DIY shopping estimate, not a structural certificate.

Frequently asked questions

How many OSB sheets for a 2×1.5 m shed?+

Walls + floor + roof often land around 8–12 sheets of 122×244 cm once waste is included — run the calculator with your height and roof type for the exact count.

Flat roof or pitched?+

A slight lean-to (flat with fall) sheds rain with less timber; a pitched roof needs more covering area but sheds snow better. Use roofing felt or bitumen shingles outdoors.

Do I need a concrete foundation?+

Many DIY sheds sit on pressure-treated skids on concrete pier blocks or paving slabs — level and clear of standing water. Full slabs are more work but very stable.

Kit shed or build from sheets?+

Kits are faster; sheet-built sheds cost less per m² if you already have tools. This calculator sizes the DIY sheet approach — compare kit footprints on Amazon too.

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