FixMeasure
Step by step
How to build a wood fence: posts, rails and boards
A fence is only as good as its posts. This guide covers planning, setting posts so they stay straight, fixing rails and boards and hanging a gate that does not sag.
1. Check boundaries and rules
Confirm where the property line is and agree the fence with neighbours. Many places limit fence height, especially at the front of a property, and some require a permit. Before digging, contact your local utility locating service (811 in the US) so buried cables and pipes are marked.
2. Lay out the line and posts
Mark the ends and corners with stakes and run a tight string line. Posts are usually set 1.8–2.4 m (6–8 ft) apart; panels fix the spacing. Add extra posts at corners, ends and on both sides of gates. The Fence calculator counts the posts, rails and boards for your length.
3. Set the posts
Dig holes about one third of the post length deep, or at least 60 cm, and deeper than the frost line in cold climates. Hole width should be about three times the post width. Put 10–15 cm of gravel in the bottom for drainage, stand the post on it, plumb it on two sides and brace it. Fill with concrete, sloping the top away from the post, or with well-compacted gravel. Use posts rated for ground contact or set them in metal post anchors. The Concrete calculator helps with the quantity.
4. Fix the rails
When the concrete has set, cut posts to a level line and fix two or three horizontal rails between them with galvanized or stainless fixings. Keep the top rail level or follow the slope evenly.
5. Attach the boards
Fix boards with two screws or nails per rail, using a spacer for even gaps, and keep the bottom 5 cm clear of the soil to prevent rot. Check plumb every few boards.
6. Hang the gate
Gate posts carry the most load, so make them larger and set them deeper. Build the gate with a diagonal brace running from the bottom of the hinge side to the top of the latch side, so it does not sag.
7. Finish and maintain
Treat the wood with a stain or oil and renew it every few years. Keep plants and soil away from the bottom of the boards. If you are planning a garden next to the new fence, our sister site PlantWhy has growing guides, for example Growing vegetables on a balcony: a practical container guide.
Common mistakes
- Digging without having underground utilities located.
- Post holes too shallow, so the fence leans after a winter.
- Setting posts in concrete with no gravel drainage, which rots them.
- Letting boards touch the soil.
- A gate brace in the wrong direction, so the gate sags.
Frequently asked questions
How deep should fence posts be?
About one third of the post length, at least 60 cm, and below the frost line in cold climates.
How far apart should fence posts be?
Usually 1.8–2.4 m (6–8 ft), or the width of your fence panels.
Concrete or gravel for fence posts?
Concrete is stiffer; compacted gravel drains better and makes replacement easier. Both work if the post is ground-contact rated.
Do I need a permit for a fence?
It depends on your location and the fence height. Check with your local authority.
How do I stop a gate from sagging?
Use strong, deeply set gate posts and a diagonal brace from the lower hinge corner to the upper latch corner.