Looking for Cheap Greenhouse Polyfilm

[Odysseus]

I have seen many websites about Greenhouse Polyfilm.  All celebrate their percentage of UV protection.  However their prices seem to reflect more of the use of the plastic rather than the quality.  If it's for a greenhouse it is worth hundreds but if you paint your house and need a dropcloth it's 30 bucks.  

So, here's my question.  Has anyone ever trusted their greenhouse to 6-mil Clear poly normally purchased from Home Depot or Lowe's as a painting drop cloth?  Or Does anyone know it's percentage of UV protection?

Plus, I will need a shade cloth for this temporary greenhouse.  (Not a seasonal one, simply temperary until we move and build a better greenhouse on the new land.)  Where can you find a shade cloth substitute that will block only 50%?  Will trampoline cloth be too opaque?  

Thanks for your time in reading this and any replies!!  

 

[nepenthes gracilis]

"Greenhouse" film is more expensive because of the extra durability it can withstand (extreme heat/cold). UV protection is built into it so it will not become brittle and yellow after a few years of use and the RH factor is also important. The stuff at Home Depot/Lowe's is OK for indoor use on a growchamber or sealing up a terrarium, but I doubt it would last even 2 years on a large greenhouse. It would quickly become weka and stretch and eventually break from UV radiation and (in my area) extreme cold would do a heck of a job on it.

As for shade cloth, I say a density of 50-60% is fine for CP greenhouses but if your going to grow Sarracenia and Dionaea and possibly some Drosera species I suggest shade only a portion of the greenhouse. I shade 3/4's of mine and the other 1/4 of greenhouse is left for the awakening Sarracenia and other temperate CP in the spring, like now. But in the Mid to late summer sun is harsh and would fry an N. hamata in minutes or hours, so shading is almost mandatory for nepenthes UNLESS you get natural shade from a tree or structure. As for trampoline cloth....it's similar to shade cloth but I think it would be too dark for your purposes unless you're going to grow Arisaema or orchids.

Shade material is also designed to help stand up against the sun's UV rays and it's spaced in different lengths, these opening in it determine your "shade%".

Hope that helps.

 

[Odysseus]

Sure it helps! Thanks again, as you were also the only one who posted a reply to my Building a Greenhouse thread awhile back!

I appreciate it N. Gracillis.

But, this greenhouse would be a means of providing for a greenhouse temporarily. If it will stand up to the elements until this winter I will be happy with that. Spring certainly isn't "beginning" here but it is very close and I am working hard on some greenhouse plans for this year only. (Could be shorter, depends solely on when we move)

As for the shade cloth, I will have some Neps and will shade a portion of the Greenhouse...but the dimensions of the plans are 9x14 feet. The morning sun is blocked by the house. This will be a Attached lean-to style greenhouse, only a bit wider. 14 feet wide, and connects only to 9 feet of the house. If trampoline material is much too opaque and won't stand to the elements long, what would be a good temporary solution?

 

[Tony Paroubek]

I wouldn't use the polyfilm that sold in hardware stores, even temporarily (unless your talking a week or so.. well then maybe).  The related in only the fact that they are transparent plastic films.

Greenhouses are great but they pose their own set of problems once you expose such a structure to the sun.  Venting heat and maintaining humidity are key for the Summer.  Heating if in a temperate climate in the Winter.  Water usage for the plants and electricty to run fans and whatnot are another concern.

You can get commercial shade cloth.  SOMETIMES places like homedepot have 10' wide rolls of 60% shade cloth.  These places will charge an arm and a leg though for each linear foot off the roll.  You can also buy it online in various dimensions.  Shade cloth is not exactly cheap though.  If your only dealing with a temporary situation for one Summer I would be inclined to do it the old fashioned way and use a whitewash.  Dilute white latex paint sprayed over the plastic film until it reaches the desired shading inside.  It will slowly wear off though so needs to be monitored.

This company is excellent with lots of information and FAQs as well as everything under the sun for building and equipping a small hobby house to full scale commercial International Greenhouse Company

Tony

 

[Odysseus]

Thanks Tony! That is a good idea to do a white wash. We have received more moisture here this year than normal which is why I shyed away from that tactic. But, if it is only a portion of the greenhouse, it will be worth it. Perhaps, it would help to be more specific on my plans. I know that it will help me, especially with advice from you guys with experience.

Quote[/b] ]
My plans: (Please post any discrepencies of my plans so that I may re-evaluate)

9 x 14 dimensions. East end attached to home and is 7'8" tall. Opposite end will be 6'6".

Frame will be PVC pipe 1" sch. 40 or 1 1/2" sch 40

I will dig four holes where I will cement the four corner poles into the ground providing a firm foundation without much cost for the PVC frame.

I am looking to have the following: Shaded section of greenhouse, Benches and hanging pots from above, Heating system, Fan venting outside air in to keep cool, Air conditioner, and Humidifier system normally used to humidify Violin Shops. All these will be set to thermostats to maintain conditions.

I will be able to water plants everyday so I have no need for piping. And I can check on systems easily through a window of the house that is located on the wall where the "lean-to" greenhouse connects to the home.

On the other hand, I will look into getting better covering for my greenhouse and not use that polyfilm from Home depot following the advice of Tony.

 

[Tony Paroubek]

They do make a 1yr and 2yr greenhouse grade polyfilm which is much cheaper than the 4yr type. Have a look on that website and you should see lots of options.

 

[Joseph Clemens]

<span style='font-size:12pt;line-height:100%'>Here in the desert southwest, if its outside, if its plastic, in a week or less it will crumble to dust. UNLESS, it is UV protected. If it is UV protected it will last longer than a week, but . . . hard to say how long.</span>

 

[Odysseus]

Quote[/b] (PinguiculaMan @ Feb. 23 2004,05:05)]<span style='font-size:12pt;line-height:100%'>Here in the desert southwest, if its outside, if its plastic, in a week or less it will crumble to dust.  UNLESS, it is UV protected. If it is UV protected it will last longer than a week, but . . . hard to say how long.</span>

Crumble eh?

Yeah, looks like my brother in law and I will have to go the more expensive route, just because we do care about our plants. And the sun here in the summer, like you said PingMan, will crumble the plastic to dust.

We've been looking around at those various websites and have been rethinking our approach. Polycarbonate looks appealing, especially since it will withstand high winds better and won't tear.

We just don't know yet.

I rent from my brother in law and when he moves, he plans on building a new house. There my wife and I can still stay with him, since the new house will be only 2 miles away. We will build a greenhouse there on the new land when the time comes, but with land negotiations taking a long time we have no firm decision made.

We just wanted a greenhouse that would last this year, but not break our wallets. From the looks of it, we may have to hold off for a year, and build the nice greenhouse when we move. That way we won't have to waste any money on a temporary one. We could build the dream one we've always wanted instead. Patience I suppose...patience.

 

[Joseph Clemens]

<span style='font-size:12pt;line-height:100%'>The greenhouse I am just about finished with, has side walls of corrugated single thickness polycarbonate, and I am experimenting with a double thickness, inflated poly roof. I earlier built a similar greenhouse with the double poly inflated roof in Albuquerque, New Mexico and it worked out well. When the outer layer of poly starts to fail, I replace them both (inner and outer layer).

I also use a small booster pump to increase the pressure of my purified water. I then pass it through 500 feet or more of 1/4 inch poly drip line coiled in the overhead to catch some solar energy and warm the water -- also provides some shading for the plants below.</span>