Question 1

What thickness of polycarbonate should I choose?

Accepted Answer

4 mm is only for vertical walls. 6 mm suits walls and roofs under light snow loads. 8–10 mm is for roofs in snowy regions, and 16 mm is for arched greenhouses carrying loads above 30 kg/m².

Question 2

Which way should the channels run?

Accepted Answer

The honeycomb channels should always run vertically so condensation can drain downward; on the roof, run them along the slope. Laid horizontally, water collects inside and the sheet turns green.

Question 3

Do I need to seal the ends?

Accepted Answer

Yes, with dedicated end tape or perforated tape. An open end lets dust and insects into the channels and you lose transparency within 2–3 seasons. Use tape perforated along the bottom so condensation can drain.

Question 4

How do I cut polycarbonate?

Accepted Answer

With a fine-tooth jigsaw, a circular saw, or a sharp utility knife for thin sheets — cut along a channel. After cutting, blow the swarf out of the end and seal it with tape.

Question 5

How long does polycarbonate last?

Accepted Answer

With a UV-protective coating: 10–15 years for 4–6 mm and 15–20 years for 8–16 mm. Without a UV layer it yellows within 2–3 years, so when buying, check for the UV marking on the side that faces the sun.

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