An Inexpensive, Hail Proof, PVC Pipe Greenhouse
I’ve finally built my greenhouse for my new garden. It’s a twenty by twelve foot hoop-style greenhouse with wooden ends and is covered with 11 mil woven poly. This greenhouse has some pretty cool features that I really appreciate, and I think you will too.
First of all, the poly I used to cover it is fantastic. It is a super tough woven poly that I got from Northern Greenhouse out of Manitoba. How tough is it? Well, my brother (who operates the Saskaberry Ranch near Sundre) just got pounded by hail last Sunday. The hail broke windows, shredded siding, and striped everything off of his saskatoon and raspberry bushes – but his greenhouse covered with this same woven poly was completely undamaged! Amazing! (I’ll try to post a picture if I can get one.)
Secondly, to eliminate wear and tear on the plastic, I covered edges of the wooden ends with copper pipe insulation. This foam protects the poly from the sharp edges of the wood.
Thirdly, it was very inexpensive and easy to build. The lumber was under $100, the poly was just over $200, and the pvc pipes were under $100. By the time I got all the misc. stuff, I was still under $500 total. Not bad, eh?
Being so late I only got a single row of tomatoes down one side, but next year I’ll be bursting at the seams once again! If you want to build a greenhouse like this one, check out my previous post that gives step by step instructions for building this same greenhouse. Since I’ve improved the design since then, I would recommend the following changes:
- Use wooden ends instead of plastic – and cover the ends with pipe insulation.
- Use 11 mil woven poly instead of the 6 mil.
- Put the PVC pipes on the inside of the frame rather than on the outside
Other than that, you should be able to follow all the other steps. If you do follow this design, be sure to leave me a comment – I’d love to hear (and see) what you’ve been doing!
With your donations, you can keep my greenhouse growing.
Dave or anyone,
I have 4 4′ x 4′ garden boxes. I’m thinking of building a greenhouse over a couple of these. Could someone tell me the advantages of the greenhouse through the summer? I would build a miniature one compared to the one I see on your site. And what size pvc (length) would I need? The pvc would have to bend at that 4′ x 4′ angle. Any help would be greatly appreciated. The depth of the boxes is 16 ”. Linda .. I’ve attached a picture of one of them.
I am a park naturalist, and am very interested in your greenhouse design. We raise and release monarch butterflies, and have used a screened in tent to let the caterpillars eat potted milkweed that we rotate in and out of the tent. I am wondering if anyone has ideas about how to attach insect netting, instead of plastic. I would like it to serve primarily like a screen tent instead of something that will stay warm. (summers in Ohio will roast my caterpillars with plastic.) our park is on a tight budget, so I would like to be able to remove the insect netting every fall so we can get years of use out of it . . . any suggestions would be appreciated. Thanks!
Natalie: Take a look at Northern Greenhouse Sales Polyfastener – It’s designed to use for attaching plastic, but it should work for your netting.
Linda: The biggest advantages I’ve found with my covered gardens is protection from several weather and early frosts. I’m not sure exactly what size you’d need for your 4×4 box, but you’d likely want something more flexible than the 3/4 inch PVC to be able to make such a tight curve.
Dave:
Going to starting building the 12×32 this weekend. If I go on the cheap with the 6 mil plastic does it last more than one season? Could I get 2 – 4 years out of it or is it replaced every year? The woven stuff is a lot more expensive.
Thanks.
Kerry: I’ve found that it’s worth the investment to get the better plastic. You might get a couple of years out of your 6 mil – or it could get shredded in year one. But the woven poly is tough stuff. It’ll last several seasons!
Hey Dave,
I had a couple questions. Was wondering if you ever did anything about the extra room at the top of the hoophouse? For example, if you are growing smaller plants there is still LOTS of room at the top to be utilized. Also, if you utilize this room it will be hotter up there for more warm loving pants and below for colder loving plants. But, I am not sure how you could attach shelves of any type to PVC. Any ideas? Maybe hanging with chains? Not sure.
My other question is what the inside of your hoophouse was like at extreme temperatures? I know you said your winters are often 20 below zero, but what is the inside of the house like at that temperature? I am planning on putting this up in Boulder, CO and want to know what it will feel like in the winter and when/if it will get below freezing inside the house.
Thank you! Love the design.
Jeremy: It would be great to use some of that space at the top of the hoops house. A few years ago I grew grape vines in the center of my hoophouse, so I had them climb up a trellis to the top. I’m not sure if hanging anything on the pvc would work – It might not be strong enough to support the extra weight.
As to the extreme temperatures, it really depends on the sun. Without extra heat, the night time temps are pretty close to the same inside and out. But with the sun during the day, you get much warmer inside. Perhaps as much as 15 to 25 degrees different…
In response to Jeremy’s and Dave’s last posts, would it work to build a wood frame inside the hoop house, attaching a 2×6 wood horizontal support to the inside of the PVC around midway up both sides? Would anyone have any comments or suggestions on this?
Kristen: You could do that, but unless you raised the over height of your greenhouse, your 2×6 would seriously cut into your head room.
[img]http://www.albertahomegardening.com/wp-content/uploads/2011/04/quonset hut size.jpg[/img]
Answer for question #44 Zanne posted October 7th 2010
Your trailer will not fit under a 7 foot high structure it will have to be at least 7′ 6″ tall in order for the edges of your trailer to fit under it. As shown in my illustration (not to scale). It is a basic “quonset hut” structure and the base will be 15 feet wide. Thats the basic theory of that type of structure.
am going to build hoop house using your ideas i have houn 10 mil triple layer woven cover at .16 cents at reef industries houston texas larger amounts as low as .1o cents. shipping taxes run up mine to .20 cents sq foot. am undecided on ends house will be 10 x 24 am going to use 3/4 electrical gray conduit. would use metal but undecided if i could bend to fit. this is a great site for anyone planning a hoop house btw here in central texas(northwest of austin) temps rarely below15 degrees and seldom snows hope to use small electric heater or heat lamps to cool and large fan at on end and opening at far end as some times temp in february can go as high as 90 degrees THANKS AGAIN FOR DATA
john w mcmillan
Love all of the ideas and inspiration! Just a thought- you could use the foam ‘noodle’ pool toy to insulate the PVC pipe and prevent direct contact with the poly. I plan to do this by cutting into the noodle with a jigsaw so it can wrap the pipe. The foam noodles are cheap especially at the end of swim season!
Great idea Marla! Those pool noodles would be perfect!
Really great and the directions to the original plans looks really easy to follow. Thank you for sharing it. I’ve got some terracing on my property (PT wood) and wanted to do 4-season harvesting but was wracking my brain to come up with a winter cover system and this could totally be adapted to that. I’ll be sure to post a photo later this year if the experiment works.
Just found this and will be back with more questions, but I have one comment for those up north about starting plants early. Why not have a cold frame with heater INSIDE the hoophouse for starting plants early. I am sure a small space heater would keep 4x6x2 ft high coldframe plenty warm if it was inside. Just sayin’
AWESOME! Thank you so much for posting this online! I’ll be moving in the spring of 2012 and was afraid I’d not be able to do a greenhouse (realistically, 2 or 3 for organic gardens) for a few years due to cost. I can swing this and, for an absolute beginner in handy-stuff, this looks do-able. Thanks again so much.
Ditto! What an awesome design and great that you share it! I have been drooling over the plans for weeks, going to the shops tomorrow to buy what I need, and will start my hoophouse in 2 days’ time, cant wait! I have changed to organic gardening a while ago, and now use only organic seeds as well, and will forward pics if I can! Thank you once again for the time dedicated to this site!! May all your seeds germinate, all your flowers bloom and may there be enough bees to pollinate all your plants! Regards M
Love you design and plan on building one this season in Green Bay WI. My question for you is why did you decide to move the PVC pipes from the outside of the frame to the inside?
Brian: The plastic attaches to the bottom much easier if it doesn’t have to go around each hoop! That’s why I’ve moved them to the inside.
I came across this design today & got started right away! I cannot believe how much I got done in one day and all by myself – female – no prior experience;) I have turned my 8′ x 11′ square-foot raised garden bed into a hoop-style greenhouse. (oh & was able to frame out around the 4′ x 6′ raised bed too.) Still need to purchase the 11 mil. woven poly. Here’s a picture of today’s work.
I am so happy with the process & it’s just beautiful ~
Marah: Great job! Looks fantastic!
We are using welded wire livestock panels attached to side of our barn and then covering with the greenhouse plastic. We plan on removing plastic for the winter because of snow load from barn. But the question is- will the metal panels heat up too much and damage the plastic? We have seen these on a website used as row covers but now can’t find it to ask . What do you think?
Carrie: I can’t say for sure. It may depend on the color of the metal panels. My plastic manufacturer recommends painting anything metal that touches the plastic with white paint to reflect the heat.
I built my 12′ x 16′ hoophouse in Michigan with a Gothic arch so help shed snow. I did this by installing a 90 degree pvc elbow in at the peak (actually heated them up and bent them to approx 60 degree to alleviate stress on the joint), see attached photo. I wonder if anyone has experimented with ground insulation around the edges, or is that ineffective?
Tom, your pics didn’t come through. But do try again – I’d love to see what you did.
We are planing on building a series of hoop houses with 10 – 12 peaks 30′ long and E W orientation
What would the spacing have to be between them to still receive full southern sun in the winter?
Located in west central NM
Not sure but they might be N S orientated .
Great stuff here
Thanks
Be well
Matthew: Someone wiser than I has to answer that one! That kind of math is not my expertise!
UK
Hi Dave,
I’ve got a retired 2mx1x1 deep septic tank, sealed side, so I am going to build the polytunnel over it, solar panel, and water pipe heat the polytunnel sub soil! Since the soil heating system is above the heated water reservoir, I shall use a pump, for the purpose. I may be able to integrate that from the storage battery of the Solar panel also, depending on its size.
I’ve been looking for the cheapest and best polytunnel diy, which is how I found your site.
Regards,
G
Gar: That sounds great! If you can, send us some pictures when you get that all done!
Thanks for the tips……. gardening rocks!!
Have you had any problems with polination in the hoop house and have you added a ventiation system?
Cheers
Andrew: No issues with pollination! I usually keep both the front and back doors open throughout the summer, so that’s my ventilation and it allows plenty of bugs to get inside to pollinate!
Just discovered your site. Had a couple questions & recommendation. Has anyone tried adding foil coated bubble insulation to the polar side to block heat loss and reflect sunlight? Also, has anyone added hydronic heat to the floor to speed germination?
If your readers haven’t been to builditsolar.com, they may find it helpful with heating in cold season.