Fence Building Guide: Materials, Spacing, and Post Installation
A wood fence is one of the most practical DIY outdoor projects, adding privacy, security, and property value. A standard 6-foot privacy fence costs $10 to $25 per linear foot in materials for DIY installation or $25 to $50 per linear foot installed by a contractor. For a typical 150-foot residential fence line, that is $1,500 to $3,750 in materials or $3,750 to $7,500 installed. Proper post installation and material calculation are the keys to a fence that stands straight and lasts. This guide covers everything from material selection to installation technique.
Choosing Fence Materials
Pressure-treated pine is the most affordable fencing lumber at $1 to $3 per picket and $8 to $15 per post. It resists rot and insects but tends to warp, shrink, and crack over time. Cedar costs 30 to 50 percent more but resists rot naturally, shrinks less, and weathers to an attractive silver-gray without staining.
Western red cedar is the premium choice for fencing, offering natural beauty, dimensional stability, and a lifespan of 15 to 25 years without treatment. For posts that contact the ground, use pressure-treated lumber regardless of the fence material. Cedar posts in ground contact rot faster than pressure-treated posts even with their natural resistance.
Post Spacing and Installation
Standard post spacing for a wood fence is 6 to 8 feet on center. Eight-foot spacing uses fewer posts but requires stronger rails. Six-foot spacing creates a sturdier fence that resists wind better. In areas with high winds, use 6-foot spacing and 4 by 6 posts instead of standard 4 by 4 posts.
Set fence posts in concrete-filled holes dug to one-third the total post length plus 6 inches for gravel drainage. A 6-foot fence needs 8-foot posts set 24 to 30 inches deep. Crown the concrete slightly above ground level and slope it away from the post to shed water. Allow concrete to cure for 24 to 48 hours before attaching rails.
Calculating Materials
For a standard 6-foot privacy fence with 8-foot post spacing: divide total fence length by 8 to get the number of sections, add 1 for the starting post. Each section needs 2 horizontal rails (top and bottom) and 14 to 16 pickets depending on width and gap spacing.
A 150-foot fence with 8-foot spacing needs 19 sections, 20 posts, 38 rails, and approximately 290 pickets. Add 10 percent for waste and defects. Total materials also include concrete for post holes (2 bags per post), galvanized screws or nails, and post caps.
- Posts (4x4 or 4x6): one per section plus one
- Rails (2x4): two per section (top and bottom)
- Pickets (1x6 or 5/8x6): 14 to 16 per 8-foot section
- Concrete: 2 bags (50 lb) per post hole
- Galvanized screws: 2 per picket per rail, plus rail attachment
- Post caps: one per post
Staining and Maintenance
Apply a penetrating stain or sealant within the first year of installation. Pressure-treated lumber should dry for 3 to 6 months before staining. Cedar can be stained immediately or left to weather naturally. A semi-transparent stain shows the wood grain while adding UV and moisture protection.
Reapply stain or sealant every 2 to 3 years for optimal protection. Inspect the fence annually for loose boards, leaning posts, and ground contact damage. Replacing individual boards promptly prevents larger structural failures. A well-maintained wood fence lasts 15 to 25 years.
Frequently Asked Questions
How much does a wood fence cost per foot?
Materials cost $10 to $25 per linear foot for a 6-foot privacy fence depending on wood species. Installed by a contractor, expect $25 to $50 per linear foot. A 150-foot fence runs $1,500 to $3,750 in materials for DIY or $3,750 to $7,500 installed.
How deep should fence posts be?
Set posts to one-third the total post length. For a 6-foot fence using 8-foot posts, dig holes 24 to 30 inches deep plus 6 inches for gravel drainage. In areas with deep frost lines, posts should extend below the frost line to prevent heaving.
Cedar or pressure-treated for a fence?
Cedar costs more upfront but resists warping, shrinks less, and looks better with minimal maintenance. Pressure-treated is more affordable but tends to warp and crack. For longevity with less maintenance, cedar is worth the premium. For budget projects, pressure-treated performs adequately with annual staining.
How many bags of concrete per fence post?
Use two 50-pound bags of fast-setting concrete per post for standard 4 by 4 posts in holes 10 inches wide and 24 to 30 inches deep. Larger 4 by 6 posts or deeper holes may need three bags. Pre-mix concrete directly in the hole for convenience.