Decking Calculator UK

Estimate the cost to build a garden deck in the UK. Enter deck size, material, and railing. Get total cost, cost per m², and labour/material breakdown. Informational only—consult a local builder.

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By Construction/DIY Editor | Published: Oct 23, 2025 | Reviewed by: Construction/DIY Editor

Deck Specifications

Total deck area in square meters.

Quick Preset Decks

How it works

Total Cost = (Material Cost/m² + Labour Cost/m²) × Deck Size × Multipliers. We use standard UK rates for different decking materials and railings, then adjust for levels and condition.

UK Decking Rates (illustrative):

  • Softwood: £40/m² materials, £30/m² labour
  • Hardwood: £80/m² materials, £40/m² labour
  • Composite: £50/m² materials, £35/m² labour
  • PVC: £60/m² materials, £35/m² labour

Inputs explained

Deck Size (m²)
Total area of the deck in square meters.
Decking Material
Type of wood or composite material (affects cost and durability).
Railing Type
Type of railing for safety and aesthetics.
Number of Levels
Multi-level decks require additional structure and cost more.
Current Condition
New build or replacement (replacement includes removal costs).

Example

Medium Deck: 30m², Hardwood, Softwood Railing, 1 Level, New Build

  • Material Cost: 30m² × £80/m² = £2,400
  • Labour Cost: 30m² × £40/m² = £1,200
  • Railing Cost: ~£480 (estimate for perimeter)
  • Total: ≈£4,080

Actual costs vary by location and contractor.

Tips & notes

  • Softwood decking like pine is cheaper but requires more maintenance (£1,000-£2,000 for 20m²).
  • Hardwood decking like oak is more durable and expensive (£2,000-£3,500 for 20m²).
  • Composite decking offers a balance between cost and durability, with minimal maintenance.
  • Elevated decks require additional structure, footings, and safety features.
  • Planning permission may be required for decks over 30cm high or within 20m of a road.
  • Get multiple quotes from local builders to compare prices.

FAQs

It varies, but a typical range is £1,000 to £4,000 for a standard 20-30m² deck, depending on materials and complexity.

Softwood (pine) is usually the cheapest option at £40-£50/m², but requires regular maintenance.

Usually 1-3 weeks, depending on size and complexity. Simple ground-level decks can be completed in 3-5 days.

Generally not required for decks under 30cm high. Check with your local council for specific requirements.

Hardwood or composite decking perform best in UK weather, resisting rot and moisture better than softwood.

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Disclaimer

⚠️ Important: Informational estimate based on average UK decking costs. Actual costs can vary significantly based on location, complexity, material quality, and contractor. Always get multiple quotes from local builders for accurate pricing.

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