Decking Cost Calculator
Calculate the cost of your decking project with accurate UK pricing for materials, labour, and installation.
Materials
Labour
Extras
Per m²
What This Means:
Decking Material Comparison
| Material | Cost per m² | Lifespan | Maintenance | Best For |
|---|---|---|---|---|
| Softwood | £21-31 | 10-15 years | High (annual treatment) | Budget-conscious projects |
| Hardwood | £35-55 | 15-25 years | Moderate (periodic oiling) | Premium natural look |
| Composite | £40-70 | 25-30 years | Low (occasional cleaning) | Low maintenance preference |
| uPVC | £25-40 | 20-25 years | Very Low | Wet climates |
| Aluminium | £79-119 | 30+ years | Very Low | Modern, sleek designs |
Factors Affecting Decking Costs
Size and Shape
Larger decks benefit from economies of scale, reducing the cost per square metre. Complex shapes with multiple angles or curves require more cutting and fitting, increasing labour time and material waste.
Site Access and Ground Conditions
Poor access to your garden can increase labour costs due to difficulty transporting materials. Sloped or uneven ground requires additional preparation work, foundations, or structural support.
Height and Safety Requirements
Raised decks over 300mm high trigger building regulations requiring proper balustrades, handrails, and structural calculations. This can add £50-100 per linear metre for safety features.
Regional Variations
Labour costs vary significantly across the UK. London and the South East typically see 20-30% higher prices compared to Northern England, Scotland, or Wales.
Timber vs Composite: Pros and Cons
Timber Advantages
- Lower initial cost
- Natural appearance and feel
- Easy to repair and replace boards
- Biodegradable and sustainable option
- Can be sanded and refinished
Timber Considerations
- Regular maintenance required
- Susceptible to rot and insect damage
- Can warp, split, or splinter
- Shorter lifespan than alternatives
- Ongoing treatment costs
Composite Advantages
- Minimal maintenance required
- Won’t rot, warp, or splinter
- Consistent colour and texture
- Slip-resistant surface options
- 25+ year lifespan
Composite Considerations
- Higher upfront investment
- Can fade in direct sunlight
- Limited repair options
- Expansion and contraction issues
- Artificial appearance to some
Installation Timeline
Most residential decking projects take 2-4 days to complete, depending on size and complexity:
- Day 1: Site preparation, foundation work, and framework installation
- Day 2: Decking board installation and initial fitting
- Day 3: Finishing, railings installation (if required)
- Day 4: Final adjustments, cleanup, and project completion
Factors that may extend the timeline include poor weather conditions, complex designs, elevated structures requiring building regulation compliance, or challenging site access.
Planning Permission and Building Regulations
When Permission is NOT Required
Most ground-level decks fall under permitted development rights if they:
- Are no more than 300mm above ground level
- Don’t cover more than half your garden area
- Don’t extend beyond the rear wall of your house
- Are not within 2 metres of a boundary if raised
When Building Regulations Apply
Raised decks exceeding 300mm height must comply with building regulations covering:
- Structural integrity and load-bearing capacity
- Balustrade height (minimum 1100mm for stairs, 900mm for decks)
- Handrail requirements and spacing
- Safe access and egress routes
Maintenance and Long-term Costs
Timber Decking Maintenance
Annual maintenance costs for timber decking range from £150-300 for a typical 20m² deck:
- Cleaning and preparation: £50-100
- Wood preservative treatment: £80-150
- Staining or oiling: £100-200
- Board replacement (5-10% annually): £150-400
Composite Decking Maintenance
Minimal annual maintenance costs of £30-80 for cleaning products and occasional deep cleaning services. No structural treatments required.
Total Cost of Ownership
Over a 15-year period, composite decking often proves more economical despite higher initial costs due to reduced maintenance requirements and longer lifespan.