When constructing the roof of a carport, conservatory or greenhouse, it’s hard to beat polycarbonate. Polycarbonate sheeting is made out of polycarbonate, a polymer plastic derived from a carbonic acid ester base. What all that chemistry means is that it’s absurdly durable for its light weight. It’s nigh unbreakable, hard to set on fire, highly insulated from sound and heat, and easy to install. Of course, it’s also waterproof.

In fact, polycarbonate is so strong for its weight that it doesn’t even need to be a single solid sheet, and instead is usually divided into multiple thin layers with a chamber in-between. This improves insulation. Thicker sheets of polycarbonate might use angled inner-layers to form a super-strong web structure within the sheet instead.

Because of the sheer durability of polycarbonate sheeting, the thickness of the sheeting is more about insulation and resisting being blown around by the wind rather than rain resistance. That’s partially why so many old greenhouses were able to get away with having just 16mm sheeting when nowadays it would be much thicker.  

Buy Polycarbonate Sheets

Smaller polycarbonate sheets, usually measure around the 4mm or 6mm range. These are suitable for small projects and tend to be either solid or twinwall. For instance, 4mm polycarbonate shees might be used to make cloches, which are like mini-portable greenhouses for individual plants. 6mm sheeting on the other hand might be useful for covers for fish ponds or other similarly sized garden installations. These sheets just have two walls, creating a single inner chamber.

Heavier roofing sheets might be significantly different. For instance, a 10mm might be suitable for small greenhouses, while a 16mm sheeting would be perfect for a medium-sized carport. The much larger sheets such as triplewall or multiwall are suitable for conservatories that are built into the house as well as large greenhouses and summer houses that are built as free-standing structures.

At ERoofing we stock a wide selection of thicknesses for sheeting that will get you the perfect fit for your roofing needs at an affordable price.