How to Build a Wood Fence: Step-by-Step for DIYers

Building a wood fence is one of the most rewarding home improvement projects a homeowner can take on. Beyond the immediate boost in kerb appeal, a well-built fence gives you privacy, keeps children and pets safely in the garden and marks a clear boundary. The job can look daunting, but broken down into a methodical, step-by-step process it is manageable for any committed DIYer.

Preparation comes before the first spadeful of soil. A fence is a permanent structure, so it needs to respect your boundary, local planning rules and, in the US, any homeowners' association (HOA) guidelines. In cold areas you also need to think about frost, which can lift shallow posts over winter. This guide walks you through the techniques that help a fence stand straight and stay sound.

Before you start: safety and tools

Wear eye protection, gloves and sturdy footwear throughout, and ear protection when using a saw or nail gun for long periods. If you hire a power auger, ask the hire company for its safety guidance and follow it closely: augers can kick or twist suddenly when they hit a root or stone, and two-person augers in particular need both operators braced and ready. Get a helper for lifting, holding posts plumb and hanging the gate.

Typical tools include a tape measure, pegs and string line, a spade, a post-hole digger or auger, a digging bar, a long spirit level and a post level, a saw, a cordless drill/driver and a hammer or nail gun.

1. Planning

A good fence starts with knowing exactly where it can go and how high it can be. In brief:

• Boundary: confirm where your boundary actually runs before you buy anything. In England and Wales, title plans usually show only general boundaries, so check your deeds and talk to your neighbour; in the US, a property survey will mark your pins. Many people set the fence just inside their own line.
• Height: in England a fence is generally permitted development if it is no more than 2 m (6 ft 7 in) high, or 1 m (3 ft 3 in) next to a highway used by vehicles. Listed buildings, conservation areas and properties with planning conditions may differ. In the US, height limits vary by town and HOA, so check with your local building department.
• Buried services: in the US, call 811 a few days before you dig so the utility companies can mark their lines. In the UK, ask the utility companies for plans of their apparatus and scan the line with a cable avoidance tool, then dig carefully by hand near any marked route.

Our guide to privacy fence mistakes covers boundaries, planning rules, easements and buried services in more detail.

2. Materials

Choosing the right timber makes a big difference to how long the fence stays sound. Posts sit in wet soil, so they need the most protection: use 100 × 100 mm (4×4) posts that are pressure-treated for ground contact (in the UK, look for Use Class 4, or UC4). Concrete posts are a popular UK alternative and do not rot; panels or boards slot into or fix to them.

For the rails and boards you have several choices:

• Cedar: naturally resistant to rot, pleasant to work with and less prone to warping. A favourite for good-quality fences.
• Larch: a durable, widely available UK timber that is often used untreated for boards and cladding.
• Pressure-treated softwood: usually the most budget-friendly option. Durable when treated properly, but it can warp and shrink as it dries.

Rails are typically 47 × 75 mm or 47 × 100 mm (2×3 or 2×4). For a traditional UK closeboard fence, triangular-section arris rails are often used instead, slotted into mortices in the posts, with overlapping featheredge boards nailed on. The alternative is ready-made panels fixed between the posts, which is quicker but less adaptable to slopes and odd lengths. Either way, gravel boards (concrete or treated timber) along the bottom keep the boards off the soil and can be replaced on their own.

You will also need postcrete or concrete mix, gravel for drainage and exterior fixings. Use hot-dip galvanised or stainless steel screws and nails suitable for treated timber, as the supplier recommends; plain steel can rust and leave dark streaks on the wood.

3. Layout

With your materials ready, mark out the fence line. Drive pegs into the ground at the corners and end points, then run a tight string line between them. This line marks the outer face of your posts.

To make sure corners are square (90 degrees), use the 3-4-5 rule. Measure 0.9 m along one string and 1.2 m along the other; the diagonal between those two points should be exactly 1.5 m. Any multiple of 3, 4 and 5 works, and larger units are more accurate on long runs. Adjust the pegs until the measurement is right.

Mark each post position along the line. Post spacing is commonly 1.8–2.4 m (6–8 ft) centre to centre, chosen to suit your panel width or rail length. Shorter spans make a stiffer fence that is less likely to sag, and if you are using panels, space the posts to the panel width plus the post, measuring as you go rather than marking every hole at once.

4. Post holes

Digging is the hardest physical part of the job. Hole depth is commonly about a quarter to a third of the post length, around 60 cm (2 ft) for a 1.8 m (6 ft) fence, and deeper on exposed or frost-prone sites. Follow the fence supplier's guidance for your post size, fence height and soil. Make each hole roughly three times the width of the post, so around 30 cm (12 in) across for a 100 mm (4 in) post.

If you have many holes to dig or heavy clay soil, a hired power auger saves a lot of effort; otherwise use a post-hole digger and a digging bar to break through stones and roots. Once each hole is dug, put a layer of gravel in the bottom, roughly 7.5–10 cm (3–4 in). This lets water drain away from the end of the post rather than sitting against the wood.

5. Setting posts

Stand the post in the hole and check it is plumb on two adjacent faces with a post level (a level that straps to the post). Brace it with temporary timber struts if you are working alone. Check the face is on the string line and the height is right, then add your postcrete or concrete, mixed and used exactly as the bag instructions say.

Fill to just below ground level, working the mix with a stick to remove air pockets. Then shape the top of the concrete so it slopes away from the post on all sides. This crown sheds rainwater away from the timber rather than letting it pool at the base. Let the concrete set for the time the bag specifies before fixing rails or boards, and check every post is still plumb while it sets.

6. Rails

With the posts firm, fit the horizontal rails, the frame of the fence. For a fence around 1.8 m (6 ft) tall, three rails are usual: one about 15 cm (6 in) from the top, one in the middle and one about 15 cm (6 in) from the bottom.

Fix rails by screwing them into the posts at an angle or, more easily for most DIYers, with galvanised fence brackets, which give a strong mechanical joint. Arris rails for closeboard fences fit into mortices or arris rail brackets. Check each rail with a level as you go.

On a sloping garden, choose between a stepped fence, where each section stays level and drops in steps down the slope, and a racked fence, where the rails follow the angle of the ground. Stepping suits panels, with gravel boards filling the gaps underneath; racking suits fences built on site.

7. Boards

The boards (pickets, or featheredge on a closeboard fence) are the skin of the fence. Start at one end, usually the end most visible from the house, and plumb your first board carefully with a level. Every board after it takes its line from that first one.

For a spaced fence, use an offcut as a spacer to keep gaps even. For full privacy, butt the boards tight, or overlap featheredge boards. Bear in mind that timber shrinks as it dries, so small gaps may open up over time. Fix each board with two nails or screws per rail to help stop it cupping or twisting as it reacts to sun and rain.

If you use a pneumatic nail gun, wear eye protection, keep your hands well away from the nose, disconnect the air line before clearing a jam and follow the manufacturer's instructions.

8. Hanging a gate

The gate is the only moving part of a fence and usually the first to cause trouble. Build the frame with a Z or diagonal brace running from the bottom corner on the hinge side up to the top corner on the latch side. This carries the weight of the gate back towards the hinges and stops it sagging.

Use heavier gate posts than the rest of the fence, for example 125 × 125 mm (5×5), and set them deeper or with more concrete, following the supplier's guidance, because they take the load of the gate swinging. Use sturdy exterior-rated hinges and latches, galvanised or powder-coated to resist rust. Leave a small gap of about 10–12 mm (½ in) between the gate and the latch post so the timber has room to swell in damp weather.

9. Finishing

Bare timber left to the weather will turn silver-grey and may split or check over time. A good exterior stain, preservative or paint helps protect it and keep its colour. Wait as long as the timber supplier and the finish label advise before applying it: freshly treated timber often needs time to dry before it will take a finish, while cedar can usually be finished sooner.

Semi-transparent stains are popular because they add UV protection while letting the grain show. Apply with a brush, roller or sprayer, following the manufacturer's instructions and wearing the protection the label recommends. Pay particular attention to end grain, such as cut ends and board tops, where moisture gets in most easily; treat any cuts in treated timber with an end-grain preservative.

Tip: Fit post caps to timber posts and keep soil, leaves and bark mulch away from the bottom of the fence. Keeping the timber dry at the top and bottom is one of the simplest ways to help it last.

FAQ

How deep should my fence posts be?

A common rule of thumb is about a quarter to a third of the post length in the ground, around 60 cm (2 ft) for a 1.8 m (6 ft) fence. Go deeper on exposed sites, in soft soil or where frost can push posts up, and follow the fence supplier's guidance for your post size and fence height.

Should I use nails or screws for my fence?

Screws are generally easier for DIYers: they grip well and are simple to remove if you make a mistake or need to replace a board. Ring-shank nails are also widely used for featheredge. Whichever you choose, use galvanised or stainless steel fixings suitable for treated timber to avoid rust streaks.

Does the good side of the fence have to face my neighbour?

Facing the finished side, without the posts and rails showing, towards the neighbour or the street is a common convention and is often seen as the good-neighbourly choice. In some US towns and HOAs it is a local rule, so check yours. In the UK it is not a legal requirement, although your deeds or a planning condition may say something about the fence, so it is worth checking and agreeing it with your neighbour.

Can I build a fence on a slope?

Yes. You can step the fence, keeping each section level but lower than the one before, or rack it, so the rails follow the slope. Stepping is easier with ready-made panels, with gravel boards to fill the gaps underneath, while racking suits a fence built on site and leaves a neater line along the bottom.

How long will a wood fence last?

It depends on the timber, the treatment, the quality of installation, your climate and how well it is maintained. Ground-contact treated or concrete posts, gravel boards and regular re-staining all help. Check any guarantee from the timber supplier or treatment manufacturer for its stated term and conditions.

Final thoughts

A wood fence rewards careful groundwork: a confirmed boundary, posts set plumb at the right depth with good drainage, a well-braced gate and a finish applied at the right time. Get those steps right and the rest is steady, satisfying work. If you are still choosing materials, read our wood fence pros and cons, and see privacy fence cost for what affects the budget. For help designing the garden around your new fence, explore our balcony and terrace decoration service or book a consultation.