How to Orient Your Polytunnel Correctly – A Polydome Guide

People often wonder what is the best orientation to put a Polytunnel and they are usually thinking in terms of what is best for growing, but there are practical considerations to think of first.

If you have a slope you should run the length of the Polytunnel down the slope (preferably not more than 5%). The slope should not go across the width for a number of reasons – the structure should be level so having a slope across the width means the structure needs to be lifted at one side to compensate for the slope – this may weaken the structure and require extra materials (e.g. a wider cover).

Exposure to wind is the next concern, the strongest orientation for Polytunnels is to face the gable towards the prevailing wind. This reduces the area for the wind to hit and you have the bulk of the structure reinforcing the structure. Tunnels are usually damaged from a gust to the side which causes the hoop to buckle. It is wise to choose a site that is sheltered from the prevailing winds, or if you don’t have shelter to put up a windbreak fence – but make the fence very strong or it may just become a missile to hit your Polytunnel.