Strength Guide

Greenhouse Wind and Snow load performance


We strive to give our customers the best product. For this reason, we undertook the huge task of analysing the strength of our polytunnels. This is done creating a computer-generated model of the structure and applying loads from the relevant standards shown in the table opposite.

These loads are applied to the model of the greenhouse using our structural analysis software. The software helps us to locate potential weak spots so that we can optimise our design.


Check If The Polytunnel Suits Your Location


The table below shows the wind and snow load numbers, the higher the number the stronger the greenhouse required (this usually means having a smaller space between the hoops and adding crop bars to increase the strength).


Using the maps, pinpoint where your structure is to be sited; note the colour and zone. Each zone relates to snow loading and wind speed throughout the country. Check the polytunnel wind and snow load performance table to make sure the polytunnel will perform in the area you have pinpointed. If you need further help with this, please don’t hesitate to get in touch with our sales team.

Wind Speed Map

Snow Loads Map

Once you've identified the snow and wind loads of your area, you can then choose the strength of tunnel you require. 

(Please note these snow and wind loadings do not apply to our Budget Competitor Range of structures)

These Calculation Are Based On The Following Standards

1 Drawings by N P Structures Ltd.
2 EN 1993-1-1:2005, General rules and rules for buildings
3 BS EN 1991-1-3:2003+A1:2015, UK NA General actions – Snow loads
4 BS EN 1991-1-4:2005+A1:2010, UK NA – General actions – Wind actions
5 EN 13031-1:2001, Commercial production greenhouses


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