Greenhouse Polycarbonate question

[Lorri D]

My husband and I have recently decided to buy a greenhouse for early starts and extending the growing season. We have narrowed our choice down to a Rion (EcoGrow: 6.5' x10') or Juliana (Basic 600: 6 x 9) greenhouse. We are leaning more towards the Rion for the extra length and 6mm polycarbonate walls.

We've been doing tons of searches on the web and I am still stuck on a question. Is there a "BIG" difference between 4mm dual polycarbonate and 6mm dual polycarbonate?

Also, any comments from owners of either of the two greenhouses would be really great too! Thank you so much for any help/info. Lorri D

[Cole_Robbie]

I'm just guessing, but I think in a structure that small, it's not going to matter very much. Big snows are the hardest on a structure. Stronger is always nicer, but make sure you invest in substantial anchoring to the ground. That is how hobby greenhouses tend to blow away. I don't know about your model, but often the company will tell you in the fine print that you should anchor it well to the ground, and they usually don't include the parts so people don't do it.

[Hotwired]

Since you're from Oregon, I'd lean toward the doublewall 6mm polycarbonate material rather than the 4mm. Not sure where in Oregon you are, but 6mm is much stronger for snow, and the 6mm (1/4") has a higher insulation property. Polycarbonate in general has a much higher IR transmission than glass, so I'd definitely invest in a auto opener for the roof vent panel. Polycarbonate has a 75% to 80% transmission in the visible spectrum but unlike glass, it has a 96-98% transmission in the IR wavelengths (heat) http://imageshack.us/a/img831/6562/polycarbt.jpg . I'll second the advice on staking it down or your neighbor will have a new greenhouse. My friend fastened to a 2x4 base, then secured the 2x4's by screwing them to stakes.

[kurt]

http://greenhousesandsunrooms.com/po...specifications Some interesting notes on yellowing,hail and dew accumilation.Seems like triple walls and higher mm's fare better.Neighbor here has one and his panes turned yellow and hazy fast due to our intense sun.

[Lorri D]

Thank you for your replies. I do plan on anchoring it. Hehehe, just last night, we had a storm blow in with 40 mph winds. Kinda unusual for this time of year. Lorri D

[Medbury Gardens]

Originally Posted by Hotwired

Polycarbonate has a 75% to 80% transmission in the visible spectrum but unlike glass, it has a 96-98% transmission in the IR wavelengths (heat) http://imageshack.us/a/img831/6562/polycarbt.jpg .

Thats interesting,ive started work on a second green house and i'm thinking of double layer glass,glass will work for me because we dont ever get large hail in my area.

[Hotwired]

There are three great books on Greenhouses for free download .... http://www.tomatoville.com/showthread.php?t=25627 .

I built my greenhouse out of insulated (non-tinted) patio sliding doors. You can actually remove the insulated glass panels from the frame and install them on a roof. I bought a bunch of the 6-foot patio doors with frames for $25/set on Craigslist http://imageshack.us/a/img832/9378/westwall.jpg . We have Freecycle here in the US, where you can get stuff for free.

[Medbury Gardens]

Wow they are a good size and for only 25 bucks,good score.

[mecktom]

Can you post some pictures of that greenhouse Hotwired? Sounds like something I have been thinking about.