Inputs
Recommended post size: 125mm × 125mm
Typical post length (incl. below ground): 2.40m
Results
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NAIBC / IRC codes
References & Sources
Standards Cited
- ASTM F567 — Standard Practice for Installation of Chain-Link Fence
Industry standard for fence post installation depth, concrete requirements, and panel sizing - IRC R301 — International Residential Code — Design Criteria
General structural requirements applicable to residential fencing
Formulas Used
- Panels Required:
panels = ceil(fenceLength / panelWidth)
Source: ASTM F567 - Posts Required:
posts = panels + 1 (both ends free) or panels (one end against wall)
Source: ASTM F567 — Posts at each panel junction, plus end posts where fence is free-standing - Post Depth:
depth = max(fenceHeight x 0.33, 610mm)
Source: ASTM F567 — Minimum 610mm (24") depth; one-third of fence height for taller fences - Concrete per Post:
1 x 27kg bag per post (standard); 2 bags for fences >1.5m or concrete posts
Source: Industry standard practice - Total Fence Height:
totalHeight = fenceHeight + gravelBoardHeight
Source: ASTM F567
Key Assumptions
- Standard fence panel width is 1.83m (6 ft) — ASTM F567
- Post depth is one-third of fence height with a minimum of 610mm (24") — ASTM F567
- 1 bag (27 kg / 60 lb) of concrete per standard post hole; 2 bags for taller/heavier fences — Industry standard practice
- Gravel board height typically 150-300mm — Industry standard practice