How to: Post Installation Guide

Selecting the right length post

As a timber merchant, we recommend a minimum of 600mm in the ground for the timber posts to provide maximum stability and long-term performance.

For posts which are being installed into soil, the maximum overall recommended depth is 900mm. With 600mm minimum depth in the ground, 300mm gravel drainage at base and 50mm minimum clearance above the ground level.

For posts which need to be installed into concrete, the maximum overall depth is 900mm, with 600mm minimum depth in the concrete, 300mm gravel drainage at base and 50/100mm gravel on top.

Key Distances Explained

• 600mm minimum depth provides stability and resistance to wind, movement and leaning.
• 300mm gravel drainage base improves drainage and helps prevent the post sitting in water
• 50mm clearance above ground keeps the timber off the wet ground to prevent moisture build up and rot.

Main Line Timber Tips

• Keep posts level and straight – Check each post with a spirit level and use a string line to maintain a straight fence line.
• Use suitable concrete – Ensure there is enough concrete around the post to provide a solid foundation.
• Protect the timber – Use properly treated timber suitable for ground contact.
• Consider site conditions – Taller fences, gates, windy locations and soft ground may require deeper holes or larger posts.
• Allow for drainage – Avoid creating a situation where water can collect around the base of the timber, as this can accelerate rot.