How to harvest rainwater off a Polytunnel
Rather than use plastic adhesive stick on guttering which can prove expensive and unreliable, here's an innovative and sure way of collecting precious rainwater from a Polytunnel, providing off- mains supply for remote areas or allotments.
In order to accommodate this nifty system, First Tunnels recommend installing a timber side rail at approximately 1 metre off the ground on one or both sides of your Polytunnel. This timber rail (we used 75mm x 47mm pressure treated timbers) is secured to the hoops using a series of corner clamps and intermediate clamps. The guttering brackets are then fixed to the timber rail down the length of the structure using screws to allow the trough to be secured firmly in place providing an excellent robust fit.
To ensure rainwater runs directly into the gutter, a series of timber battens (We used 19mm x 38mm pressure treated battens) may be required to close off any gaps between the guttering and the side rail.
Voila! You should now have a strong, robust alternative for harvesting rainwater off your Polytunnel. So next time the heavens open, rainwater should be collected from your Polytunnel roof and stored in a water butt until required for use.