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ironhat2

PVC hoop house construction

ironhat2
17 years ago

Over the next few weeks I will be putting up a cold frame to house plants for the upcoming winter months. In the upcoming summer, it could serve as a shade house as well.

As I have researched different construction methods over the last few months, I keep coming back to the hoop house design, and I favor PVC pipe as the material to make the hoops from.

I know schedule 80 is the best grade of pipe to use, gray or black is the preferred choice to white. I also realize that the wider I plan to build my hoop house, the bigger the PVC should be in diameter. I had wanted a 24 wide house, but may settle for 18'. I want it to be 32'long. As I said, this will be an unheated cold frame.

What has been your findings in life expectancy of Schedule 40 PVC pipe, before it begins to break down due to exsposure to the sun? I have found statements saying anywhere from 3 to 10 years. Because of the size of the structure I wish to build, I will have to use a larger size PVC pipe.

Using 1 1/4" to 1 1/2" PVC pipe is my thoughts at this time. Depending on whose site or message you read, I have seen spacing of 2', 3', even 4" for the hoops. What are your thoughts on this issue?

I plan to start out with just a 6 mil plastic from HD or Lowes for now. Will the wider spacing be sufficent to support this plastic?

Any thoughts or suggestions would be appreciated.

Dan

Comments (25)

  • nathanhurst
    17 years ago

    Paint the PVC with acrylic paint (bizarely called latex paint in the US) to stop the plasticizers destroying the film.

  • rain1950
    17 years ago

    All types of PVC are now formulated to resist UV degradation; even the white. I would doubt that snow load would be a heavy concern that far south, so a wider spacing would work fine. The Noble Institute in OK has done tons of research on hoophopuses.

    Here is a link that might be useful: Noble

  • ironhat2
    Original Author
    17 years ago

    Thanks for the tips and the site.

    Our winters have been mild of late. More worry of high winds and large hail than snow. Would perfer metal hoops, but bending is a problem.

    Dan

  • memo3
    17 years ago

    Dan, How are you planning to enclose the ends of your HH? I'm working on a similar project and haven't decided what to do with the ends yet. Lumber is extremely expensive where I live so I'm at a stand still on my decision.

    MeMo

  • ironhat2
    Original Author
    17 years ago

    MeMo,

    Most plans I saw have lumber included in the design of the ends of the PVC Hoophouse. I found one site that showed a hoop house that appeared to be all PVC construction. I'm going to try and put a link to it.

    Maybe another member can anser that question for you. I have questions as to how one would attach the sheeting to large diameter PVC pipe myself.

    Hope the link works, and is of some help.

    Dan

    Here is a link that might be useful: PVC Greenhouse

  • gldno1
    17 years ago

    I would seriously rethink using regular plastic for a covering. I did that the first year and it completely disintegrated by the end of the first season, whereas, the greenhouse film will last 3-4 years minimum.

  • rain1950
    17 years ago

    Here's work done by WSU Extension Service

    Here is a link that might be useful: Hoop House

  • erlyberd
    17 years ago

    I used 1 1/4" to build my 12x16' house last year. Everything is done except painting the pvc and installing the poly. I just never got around to it yet. I used the gray pvc thats treated for sunlight. At least thats what the sticker said.

    Go to that gardners supply. Its the same one as that. I built mine from their design.

  • ironhat2
    Original Author
    17 years ago

    erlyberd,

    Thanks for the site. I liked the design of the PVC house I saw there. Good luck with your gh.

    I have seen questions asked about using black rolled polyetheleen tubing instead of PVC from time to time. I noticed that a local Lowes is now stocking it, and I was wondering if anyone may have used this in the past for their hoop construction. I know nothing of this type of tubing, but I remember that years ago that black tubing was used a lot before PVC became so popular, and that the tubing of yesterday was almost indestructable.

    Dan

  • tsmith2579
    17 years ago

    Will you be using re-bar inside the PVC pipe? I ask this because I don't see where you mentioned it. I've seen large hoop houses using 1/2 or 3/4 inch PVC with re-bar inside. The re-bar adds strength and rigidity. You can also glue + fittings so you can put PVC pipe side spacers and strength. BTW, the re-bar is stuck down into the ground to hold the HH down. I see re-bar which must be 40 feet long being transported on flatbed trailers.

  • ironhat2
    Original Author
    17 years ago

    tsmith2579,

    I had not planned to use rebar reinforcement with my planned house.

    One of the plans that I found while searching the net called for inserting 20' pieces of rebar into 20' pieces. This is then bent over a wooden ridge pole and attached to the wooden framed green house base with electrical emt clamps and wood screws. A simple design, and one that sounds like it would hold up for some time.

    I personally over the years have not much luck with PVC holding up well over time to full exposure to the sun. It becomes brittle and eventually shatters when bumped. A freind built a small pvc misting frame to hold his hoses and misting heads over his plants just this spring. He painted it black, but bumped it a few weeks ago, and some of the PVC pipe shattered on him. While the rebar and pipe construction mentioned above seems like a good idea, I was hoping that by going with a larger diameter pipe would offset the need to use rebar.

  • organic_gnome
    16 years ago

    this is no hoop but unless ya got 2000/ 5000 to put out for a real one an ya got 300/500 then i built a 16 x24 useing 11 4x4x8 post 2 ft in earth no cement will move next sprng an ran a spar pole out of a 6 ft 2x4 at each end then ran heavy single wire from end to en on sides an center then wrap sides with hog wire then cover roof with it no pvc no broken green house then i cover with 6 mill green house shetting i spent an extra 29 an got the condensation thermal 4 yr it was only 87 bucks plus 150 shipping handling wich if there is a supplier near you it would only cost gas to go there an i split it with buddy he bult one to so it was only 170 bucks for for wire got free from a farmer an post cost me 9 a peice so for about 325 i put it together cost ya anoter 100 for the wire if ya gotta by it so 425 not much for a varmit proof 4 yr green house thats onlyabout 8.50 a month for the first 4 yrs thenless than 4 a month tilll your old an dont want it any more ya know it also resistant to the wind an snow load factor due to the hog wire its not a hoopan a buit mor permanant but no critter crawlin in eating your gardeen an that matter a good a door an lock made from 2x4 an wire cover it to an no one gets in a hoop in a year an ya may trip an fall in if its still ther in a hoop with poly may only run ya 250 but the sheeting will be gone in 1 yr the pipe by 2 if lucky an wind an snow well a good storm an its in your neighbor yard in 100 peices minus al the labor each year an cost of shetting at a 120 well ithink ya should try one of the ones i used no worry s for 4 yrs the sinply replace roof an good to go for another 4 if inter tested iwill send yuo plans an a meterial list an basic instructs email me at techowen@gmail .com hope a see the lihgt m friend made be a beleiver i done thos hops for fears i used 1 1/4 poly an harware store 6 mill also green house material lets in more loight an less radation an doesnt block the blue uv an red spectrums as the other does an well a neccesssaty for good plant growth it like trying to grow tomatoes under a street light indoors compare to hp sodium the hoop the street light no spectrum just filtered white an a green hs sshetting a 10000 watt hps veg an blume bulb one gets ya 25 per plant an other gets 65 to 70 in same time an the twice the size so why why why ps hope this is helpful insight an with a heater/ an exhust yuo got a year around green house that doesnt condensate an mold like a cold huose can

  • joshlynch
    16 years ago

    I use 18" rebar pounded into the ground. I bend 10' lengths of PVC pipe and slide them over the rebar stakes.

    10' wide plastic works well if you push the PVC slightly into the ground. I secure the sides and end by placing black iron pipe along the length and ends attached with spring clamps. To vent, I roll up the ends and use the spring clamps to hold it in place.

    This design is very low-cost can easily withstand winds of 30mph+. It is also very easy to take the plastic on and off to access the plants. It covers a 5' wide bed.

    Choose the thickness of PVC pipe wisely, using two 5' pieces and a 90 degree elbow for the ridge if you expect snow in the winter.

  • ole_dawg
    16 years ago

    I am using 1/2 PVC Conduit and also 1/2 EMT conduit in combination. What I have built so far is quite strong and rigid. you can make the 1/2 EMT fit into the PVC fittings by using 5/8 vinyl tubing over it. It is a tight fit and then I just secure it with #8 by 1/2 sheet metal screws. The EMT will slide complete thru the PVC fitting so you can use whole lengths. I have a photo, but it is small. I am going to try and resize it and post it. The PVC alone will just not cut it. My sides/walls are a combination of 1/2 EMT and 3/4 EMT, again using the Vinyl tubing to make a tight fit and again using screws to anchor it. Email me and I will send you some photos for you to see how I do it. I am using PVC tees and 45 degree angles in combination to make my cross bracing. The top portion is all I have finished so far and only 2/3 of the entire 15 foot length. It is in 5 foot sections. All of this is so I can take it apart when I move. Email me and I will send the pics.
    Good luck
    1eyedJack and the Dawg

    The whole thing will be about 9.5 feet tall with plenty of room for a 6 foot door

  • ironhat2
    Original Author
    16 years ago

    Hey guys,

    Thanks for the info and construction tips. It is always educational and interesting reading on this forum on the way diferent folks accomplish building cold frames and green houses.

    As I stated above I have used a couple of low hoop cold frames made out of concrete reinforcement wire and wood for the last few years. They work great, but have their on issues. Hope to winter my plants different this year.

    Thanks again,

    Dan

  • markapp_yahoo_com
    15 years ago

    Suggest reconsidering the use of black frame due to excessive heat to the film that touches it. Also agree there is no point in anything but UV resistant 6 mil as a minimum covering. Shattered plastic film bits are quite a nuisance to clean up. Another location to look at for a 12 x 40 hoop house framed of 2" PVC
    www.cahe.nmsu.edu.

  • tom_va
    15 years ago

    You might want to check the total cost of everything you'll need to put up a pvc house that size and then check the prices at the link below for a frame made from metal pipe. We've put up 3 greenhouses, one cold frame, and one basket house from them. Could not find better prices anywhere on the frames. I would be wary of a pvc house that wide if you want much height to it.

    And you will not want to use plastic from Lowe's. Although it is the same thickness as greenhouse plastic, it says right on the box that it is NOT intended for greenhouse use. Our first greenhouses are going on 6 years w/ the original plastic. The big house [not from GS] might need to be replaced next year but only because of the design of the house itself, which has rubbed a whole through both layers of plastic at the top bend.

    Good luck.

    Regards,

    Tom

    Here is a link that might be useful: Grower's Solution

  • erlyberd
    13 years ago

    Well, to the original poster, how did it work out for its first winter? My PVC gh took everything mother nature could throw its way, including over a foot of heavy snow, wild winds and is still standing! Yep, I'm still in dis-belief on what a properly designed pvc gh can withstand!

    What about you?

  • gmom2-6boys
    13 years ago

    ironhat2,
    Now that you have had the hoophouse for a while. How do you like it? Has it performed to your expations. How have you used it? Did you paint your frame? What color should you use?
    I have a 9x13' pvc frame and used it the first year I had it.Loved it! But then it started breaking down. Never used it after that. I'm hopping to get it back into use again.
    But...I have read that you can point the frame to keep the plastic from breaking down. Does that really help?
    Thanks
    gmom

  • the_pepper_guy
    13 years ago

    Just wanted to throw in a pic of the greenhouse I just built, well, I just "modified" my old one. It has been great in all weather, including high winds. Made with just schedule 40 PVC with painters plastic. I have to replace it every year, but no biggie.

    {{gwi:301706}}

    If anyone is interested in one like this, I have posted some basic plans with pics on my blog.

    Here is a link that might be useful: The Pepper Guy's Blog

  • Bryan Davidson
    7 years ago

    In regard to ironHat's post 9/9/2006: today's pvc is uveitis ray resistant. The most likely reason the pvc shattered was because water got trapped in the pvc pipe over the winter months. If water is allowed into pvc pipe, and there are no drain holes or other ways for pvc to drain, the expansion from water freezing causes pvc pipe to shatter. This shattering is well known in the sprinkler industry and is why sprinkler systems' water is air blown out every fall during the winterizing process. Shattering from freezing water trapped in sch 40 pvc is a known fact. I don't know if this happens to the schedule 80 type pvc as well?

  • Bryan Davidson
    7 years ago

    I would like to thank everyone that posted comments on this page. All of it was very educational to me. Awesome! Grow on my friends, grow on!

  • HU-781372368
    4 years ago

    I am wondering how you all are getting the 1 1/4 or 1 1/2 pvc to bend to make thw arch

  • HU-265329416
    4 years ago

    Anyone have a preference on attaching PVC to the inside of the frame or the outside? I am using 3/4” PVC, 10’ x 16’ house with a treated lumber frame.