Fence Installation Guide

Post Depth Rule

For fences up to 1.5m: minimum post depth of 450–600mm. For 1.8m fences: 600mm minimum, 750mm on exposed or windy sites. Rule of thumb: post depth = 1/3 of total post length. A 2.4m post (giving 1.8m above ground) needs 600mm buried.

Concrete Quantities

Each post hole typically needs a mix 300mm in diameter, 600mm deep = approximately 0.042 m³ = about 1.5 bags of 25kg postcrete. Postcrete is a rapid-set product that sets around the post in minutes when water is added.

Metal vs Timber Posts

Galvanised steel post spikes avoid concrete and can be quicker to install on firm ground. Metal posts last significantly longer than timber. For fence panels, steel H-frame posts designed for your panel size are the most secure and best-looking option.

Safety and Regulations

Most structural and electrical DIY work in England and Wales must comply with Building Regulations and is notifiable to local Building Control. Work that is not notifiable (like-for-like replacements, cosmetic changes) can be done without notification. Notifiable work done without approval is technically illegal and can cause problems when selling the property. Electrical work in most rooms requires a Part P competent person or Building Control inspection. Gas work must always be performed by a

Fence Post Calculator

Results update automatically as you type

Enter values above to calculate