United Kingdom calculator
Deck Building Cost Calculator
Estimate the cost to build a garden deck in the UK. Adjust the deck size, the decking material, whether it is ground-level or raised, and whether you add a perimeter balustrade and a step run to see an itemised low–high range in pounds (VAT inclusive) per square metre for your project.
How this calculator is built
Unit costs with sources
This model cites 6 sources for its line-item cost and regional labour inputs.
Regional labour adjustment
The region table applies local labour indexes only to labour-heavy line items.
Published methodology
The methodology page lists the formula, size drivers, labour model, and source links.
How this estimate is calculated
The model prices 5 project line items from published cost inputs. Quantities are driven by the deck's size, the decking material, whether it is ground-level or raised, and whether it includes a perimeter balustrade and a step run. The selected scope and finish adjust those inputs, then the regional index changes only each line's labour share; material prices remain national.
The itemised midpoint is shown as a ±25% planning range. It is not a contractor quote: access, design choices, permits, availability, and site conditions can move the final price.
VAT
The calculator applies the configured standard UK VAT rate of 20% to its renovation estimate and shows the VAT-inclusive total. Some projects or properties can qualify for different treatment, so confirm the rate and any exemptions on each contractor quote.
How firm these costs are
The national renovation model is assembled from the public cost guides cited for its individual inputs, then calibrated against a cited market range. Individual line prices are planning allocations rather than live quotes; compare the result with itemised quotes from qualified contractors before budgeting.
Estimate your project
Change the default inputs to match your scope. The breakdown updates by line item.
Deck Building Cost by region: typical ranges
Each range applies that region's labour index to the labour-share line items of the default project; materials stay at national prices. Select a region for its full local breakdown and calculator.
| Region | Typical range | Labour index | Permit |
|---|---|---|---|
| East Midlands | £3,649–£6,081 | 95% | Usually none |
| East of England | £3,649–£6,081 | 95% | Usually none |
| London | £3,943–£6,572 | 112% | Usually none |
| North East | £3,649–£6,081 | 95% | Usually none |
| North West | £3,666–£6,110 | 96% | Usually none |
| Scotland | £3,735–£6,225 | 100% | Usually none |
| South East | £3,804–£6,341 | 104% | Usually none |
| South West | £3,926–£6,543 | 111% | Usually none |
| Wales | £3,701–£6,168 | 98% | Usually none |
| West Midlands | £3,649–£6,081 | 95% | Usually none |
| Yorkshire and the Humber | £3,631–£6,052 | 94% | Usually none |
Common questions
How much does it cost to build a deck in the UK?
Supplied and fitted, softwood decking typically runs about £70–£90 per m² and composite about £90–£110 per m², so a mid-grade 30 m² deck with a wooden balustrade lands around £5,000–£6,000 including VAT. Our figures work from ex-VAT trade rates and then add the standard 20% VAT, so the headline total is the real bill you pay.
Is composite decking worth it over timber in the UK?
Composite costs more up front — often 30–50% above pressure-treated softwood — but it does not need annual sanding, staining, or re-oiling and resists the algae and slipperiness that plague timber decks through wet British winters. Softwood is cheapest to install; capped composite sits at the top. The 'Decking material' selector scales the estimate across these tiers.
Do I need planning permission for a deck?
In England a ground-level deck no more than 300 mm above the ground, taking up with other structures no more than half the garden, is normally permitted development needing no application. A raised deck, a listed building, or a conservation area can change that, and Scotland's building warrant rules differ — check with your local authority. Toggle 'Raised / elevated deck' and 'Include a stair run' to reflect the extra structure a raised deck needs.