Switching from RO to UF membranes made my life way easier

Composite just doesn’t cut it for anything more than basic debris.

I get what you’re saying, but I’m still on the fence. Metal’s definitely tougher, but I hate how hot it gets in summer - my roof garden turned into an oven. Anyone tried thick polycarbonate? Wondering if it’s a middle ground or just another critter snack.

Anyone tried thick polycarbonate? Wondering if it’s a middle ground or just another critter snack.

Had a similar dilemma a few years back. Metal was just brutal in the heat - my tomatoes basically roasted themselves. Gave 16mm twinwall polycarbonate a shot. It’s held up better than I expected, especially against hail and squirrels (though raccoons did manage to scratch it up a bit). Not as cool as shade cloth, but definitely doesn’t trap heat like metal. Only thing is, after about five years, it started to yellow a bit. Still, for me, it’s been a decent compromise.

Switching from RO to UF membranes made my life way easier

- Used 10mm polycarbonate panels for a couple of greenhouse projects. Not as thick as 16mm, but still pretty sturdy.
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“Gave 16mm twinwall polycarbonate a shot. It’s held up better than I expected, especially against hail and squirrels (though raccoons did manage to scratch it up a bit).”

- In my experience, polycarbonate is a solid middle ground. It won’t stop a determined raccoon, but nothing short of steel really does.
- Metal panels are a nightmare in summer. Had one tenant complain their lettuce “cooked on the vine.” Polycarb keeps things way more stable.
- Only real downside: after about 4-5 years, yellowing and some brittleness start to show up. Not a dealbreaker, but worth budgeting for replacements down the line.
- Critters mostly leave it alone, but if you’ve got raccoons or possums, expect scratches and maybe some gnaw marks. Squirrels don’t seem to care much.
- Install is straightforward - lighter than glass, easier to cut. Just make sure to seal the edges or you’ll get algae/mold inside the channels.
- If you’re in a high-wind area, secure it well. I’ve seen panels go flying during storms if not anchored right.
- Cost-wise, it’s more than basic plastic sheeting but less than glass or metal. Decent ROI if you’re not looking for a forever solution.

If you’re after something that balances heat control and durability without breaking the bank, thick polycarbonate’s probably your best bet. Just don’t expect it to be invincible - especially if your local wildlife is on the aggressive side.

I get the appeal of polycarbonate, especially for greenhouses where weight and insulation matter. One thing I’d push back on a bit - if you’re in a really humid area, that yellowing and brittleness can show up sooner than 4-5 years. I’ve seen panels start to haze up after just three summers, particularly on south-facing sides. Might be worth considering UV-resistant coatings or films if you want to stretch their lifespan. Also, if you’re dealing with raccoons, sometimes a metal mesh over the panels helps more than folks expect... not pretty, but it does the trick.

- Had a similar issue with polycarbonate on my shed roof - south-facing panels started to haze after just two years. Humidity here is brutal, so I get what you’re saying.
- Tried a UV-resistant spray last time. Helped a bit, but honestly, nothing’s perfect if you’re in a wet climate.
- For critters, I rigged up some leftover hardware cloth over the panels. Not the prettiest, but raccoons haven’t gotten in since.
- If you’re thinking about switching materials, I’d weigh the cost of replacing panels vs. adding coatings or mesh. Sometimes it’s just easier to budget for a refresh every few years.