Wood Fence Calculator - Posts, Rails & Pickets
Building a privacy or picket fence? Calculate the exact lumber list: Posts, Rails, and Pickets needed for your yard with accurate material estimates.
Fence Diagram
Fence Dimensions
Measure the perimeter you want to fence
Privacy blocks view, Picket allows airflow
Check local zoning regulations
Pro Tips
Set posts first and let concrete cure 24-48 hours before adding rails.
Use treated lumber for posts and anything touching the ground.
Add 10% extra material to account for cuts, mistakes, and waste.
Material List
100ft Privacy Fence • 6ft Height
8ft length
8ft boards
6ft boards
5lb boxes
Bags of Concrete Needed
For setting 14 fence posts (1.5 bags per post)
Calculate Precise Amount →
Estimated Cost Breakdown
Prices are estimates. Check local lumber yards for current pricing.
Complete Wood Fence Building Guide
Understanding Fence Material Calculations
Building a wood fence requires precise material calculations to avoid costly trips back to the lumber yard. Our fence calculator uses industry-standard spacing and measurements to ensure you have everything you need for your project.
Standard Fence Measurements:
Post Spacing: 8 feet on center (industry standard)
Formula: Total Length ÷ 8 = Number of Posts (rounded up + 1)
Rails Per Section: Typically 2-3 horizontal rails
4ft fences use 2 rails, 6ft+ fences use 3 rails for stability
Picket Calculation: Based on picket width plus gap
Privacy: No gaps | Picket: 2" standard gap between boards
Privacy vs. Picket Fence Styles
Choosing between privacy and picket fence styles depends on your needs for security, aesthetics, and airflow:
Privacy Fence
- Complete visual blockage
- Maximum security and privacy
- Better wind barrier
- Noise reduction
- Uses more materials (higher cost)
Picket Fence
- Classic decorative appearance
- Better airflow
- Lower material costs
- Friendly, open appearance
- Limited privacy
Essential Materials Breakdown
Understanding each component ensures a sturdy, long-lasting fence:
1 Fence Posts (4x4 Treated)
Posts are the structural foundation. Use pressure-treated lumber rated for ground contact. Posts should be buried 1/3 of their total length (e.g., 6ft fence needs 8ft posts with 2ft underground).
Spacing: 8 feet on center (standard) | 6 feet (heavy-duty) | 10 feet (economy)
2 Horizontal Rails (2x4)
Rails connect posts and support pickets. Most fences use 2-3 rails depending on height. Top and bottom rails are essential; middle rail adds stability for taller fences.
Quantity: 4ft fence = 2 rails | 6ft fence = 3 rails | 8ft fence = 3 rails
3 Pickets/Boards
Vertical boards that form the fence face. Common sizes: 1x4, 1x6, or 1x8. For privacy fences, pickets are placed touching or overlapping. For picket fences, leave 2-3 inch gaps.
Width: 5.5" actual (1x6 nominal) is most common for privacy fences
4 Fasteners (Screws/Nails)
Use galvanized or coated exterior screws to prevent rust. 2.5-3" screws for pickets, 3-4" for rails to posts. A 5lb box contains approximately 1,000 screws.
Pro Tip: Deck screws work better than nails - they don't pop out over time
Step-by-Step Fence Installation
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1
Plan Your Layout
Mark corner posts with stakes. Run string between corners to establish fence line. Mark post locations every 8 feet. Check local building codes and property lines.
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2
Dig Post Holes
Dig holes 1/3 the post height (e.g., 24" for 6ft fence). Use post hole digger or auger. Holes should be 3x post width (12" diameter for 4x4 posts). Add 4-6" gravel base for drainage.
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3
Set Posts in Concrete
Place posts in holes, check plumb with level. Brace posts temporarily. Mix and pour concrete (1.5-2 bags per post). Slope concrete away from post for water drainage. Let cure 24-48 hours.
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4
Install Rails
Mark rail positions on posts (typically 6" from top/bottom). Cut rails to fit between posts. Attach with 3" deck screws (2 per connection). Use level to ensure rails are straight.
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5
Attach Pickets
Start at a post or corner. Use spacer for consistent gaps (or butt boards together for privacy). Attach each picket with 2 screws per rail. Check plumb every 5-6 boards. Keep tops level using string line.
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6
Add Caps and Finish
Install post caps to shed water. Trim picket tops if desired. Sand rough edges. Apply stain or sealant within 6 months to protect wood from weather.
Cost Considerations
Wood fence costs vary by material choice, height, and location. Here's what to expect:
| Fence Type | Cost Per Linear Foot | 100ft Total |
|---|---|---|
| 4ft Picket Fence | $15-25 | $1,500-2,500 |
| 6ft Privacy Fence | $25-40 | $2,500-4,000 |
| 8ft Privacy Fence | $30-50 | $3,000-5,000 |
Money-Saving Tips
- Buy lumber in bulk or during off-season sales (typically fall/winter)
- Use standard 8ft spacing instead of 6ft to reduce post count by 25%
- DIY installation saves $10-20 per linear foot in labor costs
- Consider cedar pickets with pine posts/rails for cost-effective durability
Frequently Asked Questions
Q: How deep should fence posts be buried?
A: Posts should be buried 1/3 of their total length. For a 6ft fence, use 8ft posts with 2ft underground. In areas with frost, go below the frost line (typically 30-36 inches).
Q: What's the best wood for fence posts?
A: Pressure-treated pine rated for ground contact (.60 retention) is the industry standard. Cedar and redwood are naturally rot-resistant alternatives but cost 2-3x more.
Q: How long does a wood fence last?
A: Treated pine lasts 15-20 years with proper maintenance. Cedar and redwood can last 20-30+ years. Regular staining/sealing every 2-3 years extends lifespan significantly.
Q: Can I build a fence on a slope?
A: Yes. Use either stepped panels (posts remain vertical, panels step down) or racked/contoured fencing (follows slope). Stepped is easier for DIY and more common.
Q: Do I need a permit to build a fence?
A: Most areas require permits for fences over 6 feet tall. Check local building codes, HOA rules, and property line setback requirements before starting.
Important Safety & Legal Considerations
- Call 811: Always call before digging to locate underground utilities (gas, electric, water lines)
- Survey property lines: Build 6-12 inches inside your property to avoid disputes
- Wear protective gear: Safety glasses, gloves, and hearing protection when cutting lumber
- Check HOA rules: Homeowners associations often restrict fence height, color, and style