What you'll need
Any deck used for public access (a rental property, commercial premises) has more stringent requirements including railing height regulations.
Step-by-step guide
- Plan and get permissionsDecks over 300mm high or over 50% of the garden may require planning permission. Check with your local planning authority. Decks adjoining listed buildings or in conservation areas have additional rules.
- Set out the frameMark the deck area with string lines and pegs. The frame must be perfectly level — use a long spirit level or a water level. Post positions are typically no more than 1.8m apart.
- Install posts or frame supportsFor decks over 150mm off the ground, concrete posts into the ground (min 600mm deep, more in soft ground). For low-level decks, use adjustable ground screws or concrete pads with post bases — this avoids wood-to-ground contact which causes rot.
- Build the frameUse 100x47mm C24-graded timber for the frame (joists and rim joist). Treat all cut ends with end-grain preservative. Joists at 400mm centres for 32mm boards, or 600mm for 38mm boards. Check diagonal measurements to confirm the frame is square.
- Lay the deck boardsUse stainless steel screws (never galvanised — they stain the wood). Pre-drill to avoid splitting. Leave a 5-8mm gap between boards for drainage and movement. Start with a straight board along the house and work outwards. Trim the outer edge straight with a circular saw once all boards are down.
- Finish and maintainApply decking oil or stain within 1 week of laying — raw timber degrades quickly. Use a product with UV protection and reapply annually.
Coat all timber with preservative before assembly, not just after. The hidden parts of the frame (inside faces of joists, top of posts where they contact the board) are where rot starts.
Expert tips for the best result
- Hardwood decking (Ipe, Cumaru, Balau) lasts 25+ years with minimal maintenance; treated softwood lasts 10-15 years with annual oiling
- Composite decking looks great on day one but can feel plastic and gets very hot in direct sun
- The frame matters more than the boards — a perfect frame in treated timber with good drainage will last 20 years
- Point the ends of boards away from the house to shed water off the deck rather than towards the building
- Leave a 10mm minimum gap between the deck and the house wall for air circulation and to prevent damp bridging
Useful tools and products
When to call a professional builder
Decks over 600mm high (railing requirements, structural load), complex shapes around obstacles, or if ground conditions are poor (soft soil, slope, or proximity to drains).
We connect you with vetted local builders across the UK — fast response, free quotes, guaranteed work.
💬 Get a free quote via WhatsAppFrequently asked questions
How difficult is how to lay decking for a beginner?
This guide is rated Moderate. A well-built deck adds significant value and usability to an outdoor space. Timber decking is the most popular choice in the UK and a capable DIYer can achieve excellent results. The foundation (the f If you're not confident, a professional builder can do this quickly and provide a guarantee on the work.
How long does how to lay decking take?
Allow 1-2 weekends. This assumes the tools and materials are ready before you start. First-timers should budget extra time for preparation and any unexpected issues.
How much does a builder charge for this in the UK?
Most builders charge £40-80 per hour depending on location and complexity. For a straightforward job like this, expect 1-2 hours of labour plus materials. Get a fixed quote via WhatsApp — message us with your postcode and job details.
How do I find a reliable builder near me?
WhatsApp us with your postcode and job description. We match you with a vetted local builder from our network — most jobs get a response within the hour. Contact us here.