How to Price a Shed Base: Labour, Materials and Margin Guide

Quick Answer: A shed base in the UK prices at £350–£700 for a small paving-slab base (up to ~6×4ft), £700–£1,500 for a typical concrete slab base (8×6 to 10×8ft), and £1,200–£2,800 for a large concrete base with a reinforced edge or for a garden room footing. Plan half a day to two days on site. Most of the price is groundworks labour and the sub-base, not the concrete itself — a C20/C25 mix is cheap; the digging, hardcore, compaction and shuttering are where the hours and the margin sit.

Summary

A shed base looks trivial and is one of the most commonly under-priced jobs in landscaping and groundworks. The error is always the same: the customer (and sometimes the tradesperson) prices "a bit of concrete" and ignores that 60–80% of the work is in the ground — excavating topsoil, laying and compacting a hardcore sub-base, setting levels, shuttering, and clearing the spoil. Concrete itself is the cheap part. The job that loses money is the one quoted on the visible slab and not on the dig.

Three things drive the price: the base type (paving slabs, poured concrete, or a plastic grid system), the size and how square/level the ground is, and access for getting materials in and spoil out. A flat, accessible garden with good access is a half-day job; a sloping plot with a long barrow run and clay spoil to remove is two days. For anything load-bearing beyond a light timber shed — a garden room, a hot tub, a heavy workshop — the base becomes a genuine structural slab and may engage Approved Document A; that is a different price bracket and you must spot it at quote stage.

This guide covers the three base systems, 2026 UK material costs, realistic labour, the labour/materials split, target margin, and the pricing mistakes that turn a quick earner into a loss. For poured slabs over a wider area see oversite concrete slab; for getting the mix right see concrete mix ratios guide; to estimate volume use concrete volume; for the heavier garden-room footing see garden rooms.

Key Facts

Quick Reference Table

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Job Labour Materials £ Typical price £ Notes
Paving-slab base (up to 6×4ft) 0.5 day £80–£200 £350–£700 Sub-base + slabs; cheapest option
Plastic grid base (8×6ft) 0.5–1 day £120–£260 £450–£900 Fast, permeable; over compacted hardcore
Concrete slab (8×6ft, 100mm) 1 day £180–£400 £700–£1,300 C20/C25; sub-base + shutter + pour
Concrete slab (10×8ft, 100mm) 1–1.5 days £300–£600 £1,000–£1,800 Larger pour; spoil removal adds cost
Reinforced slab (heavy workshop) 1.5 days £450–£800 £1,400–£2,400 Mesh + thicker pour
Garden-room / hot-tub footing 1.5–2 days £600–£1,200 £1,800–£3,500 Structural; may engage Part A
Spoil removal (skip) — £150–£280 £150–£300 add-on Itemise; clay/soil fills fast

Detailed Guidance

Labour time — it's the dig, not the pour

A flat, square, accessible 8×6ft concrete base is a comfortable one-day job for two: strip the topsoil to depth, lay and wacker-compact 75–100mm of MOT Type 1, set the shuttering to level and fall, lay the DPM, then pour and tamp the concrete. A small paving-slab or grid base on good ground is a half day. The hours balloon when the ground works against you — a slope needs cut-and-fill or stepped levels, clay needs more digging and generates heavy spoil, and tree roots or buried rubble can stop a hand-dig dead.

Access is the silent labour multiplier. A long barrow run from the road, no side access for a digger, or a customer who won't let a concrete pump near the lawn can double the labour on an otherwise simple base. Walk the access route at survey. Above roughly 12m² or on hard ground, a mini-digger pays for itself; below that, price the dig as hand labour and be honest about the hours.

Materials & 2026 prices

Concrete is cheap: C20/C25 ready-mix is £110–£150/m³, and a typical 8×6ft × 100mm slab is only about 0.45m³. The catch is the part-load surcharge — small pours attract minimum-charge premiums, so for tiny bases bagged concrete (£4.50–£6.50/25kg) can be cheaper despite the labour. Use concrete volume to size the order and avoid both shortfall and waste.

The sub-base is the real material spend on most jobs: MOT Type 1 at £45–£70/tonne, plus a sharp-sand blinding layer. Paving slabs are £8–£20 each; plastic grid systems are £10–£18/m² and need a compacted hardcore bed and membrane underneath — they are not a lay-on-grass shortcut. Add DPM, shuttering timber, and mesh on heavier slabs. Itemise sub-base, concrete/slabs/grid, membrane and reinforcement separately so a customer comparing quotes can see why a proper base costs more than the cowboy's.

Regional rates & access

Groundworkers and landscapers charge £160–£260/day across most of the UK, £220–£320 in London and the South East; a mate is £120–£200/day. Plant hire (mini-digger £80–£150/day, wacker £30–£60/day) is a billable line, not an absorbed cost. The biggest regional/site variable is spoil removal: a 4-yard skip is £150–£280 and soil/clay fills it fast, so on any real dig the skip or muck-away is a line item the customer must see — not a surprise on the final invoice.

Margin — what good looks like

On a £1,000 standard concrete base, materials and plant might be £350–£500 and labour cost £200–£350, leaving a sound net once overhead is covered — bases are profitable when the dig and spoil are priced honestly. Target a net margin of 25–35%; small bases can carry a higher percentage because the minimum call-out and travel are loaded in. The base goes underwater when the dig is under-scoped, the skip is forgotten, or a part-load concrete surcharge is missed. Price the ground, the spoil and the access — the concrete almost never breaks the job.

Structural & permitted-development considerations

For a light timber garden shed, a base is not normally a structural concern and the shed itself is usually permitted development (broadly, outbuildings under set size and height limits — commonly cited around 15m² without further conditions and up to 30m² with conditions; always check the specific permitted-development limits and any conservation/listed constraints). But once the structure is a garden room, a heavy workshop, a hot tub, or anything people occupy or that carries real load, the base becomes a structural slab and Approved Document A (structure) can apply, alongside other Building Regulations if it is a habitable room. That is a different design and a different price. Spot it at quote stage — quoting a habitable garden room on a shed-base price is the most expensive mistake in this category.

Red flags — load the price or step back

What to itemise on the quote

Separate lines for: excavation/dig (to depth, with area); spoil removal (skip or muck-away); MOT Type 1 sub-base and blinding; concrete or slabs or grid system; DPM/membrane; shuttering; mesh reinforcement (if used); plant hire (digger, wacker); and labour as crew-days. An itemised base quote wins against a lump sum because it shows the customer the sub-base and spoil work a cheaper quote has quietly left out — and it protects you when the ground turns out worse than the survey suggested.

Frequently Asked Questions

Why does a shed base cost more than the concrete in it?

Because most of the work and material is below the slab. Excavating topsoil, removing spoil, and laying and compacting a hardcore sub-base is the bulk of the labour and a large share of the materials. The concrete is cheap; the groundwork is not. A quote that only prices the visible slab is the one that loses money.

Concrete, paving slabs or plastic grid — which to quote?

Paving slabs are cheapest for small, light sheds on good ground. Plastic grid systems are fast and permeable but still need a compacted hardcore bed. Poured concrete is the durable choice for anything heavier or permanent and is essentially required for garden rooms and heavy workshops. Match the system to the load and the ground, and price each on its own merits.

Does a shed base need Building Regulations or planning permission?

A light timber shed is usually permitted development within size and height limits, and its base is not normally a structural concern. But a garden room, habitable outbuilding or heavy structure can engage Approved Document A (structure) and other Building Regs, and may need planning. Identify which you are quoting before you price it.

How much concrete do I need for a standard base?

A typical 8×6ft slab at 100mm thick is roughly 0.45m³; a 10×8ft slab around 0.75m³. Use concrete volume to calculate exactly and add a small allowance for over-dig. Watch for ready-mix part-load surcharges on small pours — sometimes bagged concrete is cheaper despite the extra labour.

Regulations & Standards