Can I Build a Commercial Polytunnel with a Basic Polythene Cover?
A simple garden polytunnel sheet can look close enough to a professional film when it is still on the roll. It is clear, flexible and keeps rain out. For a small domestic frame, that may be fine. For commercial polytunnels, the cover has a harder working life. Wind load, crop value, light levels, condensation and frame length all matter. So yes, you can physically put basic polythene on a commercial tunnel. But for commercial polytunnels that earn money, it may be a false economy. Why the cover matters at a commercial scale Once the bay gets longer and wider, the sheet starts taking a fair bit of punishment. Commercial polytunnels tend to sit higher, run further and catch more weather than a back garden frame. Thin polythene film soon shows its weak spots around doors, crop wires, hoops and fixings, because that is where movement keeps nagging at it. The growing environment matters too. Good polytunnel covers are not only a waterproof skin. They affect light transmission,...