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!
211 replies on “An Inexpensive, Hail Proof, PVC Pipe Greenhouse”
This looks very good. It seems to me in making some enquiries several years ago, I was told not to use black as it absorbs too much heat. ie; your end covers. This then deteriorated the poly quicker. I need to check this out. I am impressed with the total price. Good work.
Clayton
Yes, I considered that when I used it, but because it is insulation, I figured it wouldn’t hold the heat. If it was just black plastic or something like that, then I wouldn’t have used it.
HI,I want to build a greenhouse and I would like to know where to buy the white pvc “hoops” 20ft long and is 3/4 ins big enough?Thank you, Robert
I got this PVC pipe from UFA and yes, 3/4 is size I used.
I have been wanting to build a greenhouse for a while now and you have just inspired me to do it. Thanks for the great tips.
Great ideas Dave. I like the improvements on your new design,
1) woven poly
2) PVC pipes on the inside
3) wooden ends
4) pipe insulation on the edges
Here is a suggestion that would help relieve the stress at the nails.
Before you lay the plastic, nail 1×2 strapping along the outside of the 2×6 framing, flush with the top edge.
As you lay the plastic, use a second length of 1×2 strapping. Place the strapping on top of the excess plastic and roll the plastic so that the plastic goes behind the strapping first. You will need about an extra 6 inches of plastic at the bottom to do this.
The tricky part is you have to do the whole length all at once. An extra pair of hands will help.
Now nail this roll to the 2×6 framing tight and flush underneath the first 1×2 strapping.
All the stress on the plastic is now on the edges between the two strapping and not on the holes made by the nails.
Hope this helps.
Hi I thought I’d let you know that I found this list of Urban Gardening projects on the Westworld magazine website.
http://www.ama.ab.ca/westworld/index.php?/articles/10_urban_garden_projects/
Hi Dave,
This was the second season for my hoopstyle greenhouse and again it has produced abundantly! I love it. In it I grow tomatoes, peppers and cucumbers. I just had a question maybe you could help me with. I’ve got so many cucumbers however some of them are bitter, while the next one on the vine is just super sweet and great tasting. What causes this and how can I avoid it. Any info would be appreciated, we really enjoy your website. Thanks
Cucumbers can become bitter if the temperature is to high or is fluctuating greatly. A lack of water can cause bitterness as well. Regular watering and the use of mulch will solve the lack of water issue, but regulating temperature might be harder to control. Be sure to have proper ventilation in your greenhouse – this is the #1 cause for most greenhouse problems. Depending on the size of your greenhouse, you may require a large fan to exchange the air more frequently. Hope this helps!
I am building this greenhouse in a couple weeks; a couple questions? I am building it 12′ X 32′, is 1/2″ pvc adequate or should I go with 3/4″? Also I don’t know how the lady who made the greenhouse with the wooden ends, got 11mil woven poly for $200.00 ? When I called there my quote with shipping & tax was 369.60?? And hers was much bigger! Any help with that would be appreciated. Also to properly vent it in(Alberta), when you open the back wall, how do you attach the plastic so it doesn’t get torn by the wind? How much do you need to open the back? And what is the ideal temp. supposed to be inside? I’ve never grown anything inside a greenhouse , so are there any helpful sites in Alberta that can help me out?
I’ve built a greenhouse this year thanks to your inspiration, and started a garden blog as well. My brother-in-law had left over pipe and he loves to fabricate so he welded the frame from pipe and we plywooded the sides and used the plastic that you recommended. I built raised beds inside. Hoping to grow veggies through winter. I live in PA, zone 6 so I think this will work great. Thanks for the inspiration!
Hi Dave, You have totally inspired me!! I started to build an inexpensive greenhouse and I have the frame up with pvc pipe, LUCKILY i found your site before I went to far, because now I am going back and using the boards and the re rod and now that I have found your “improved” version I am even more excited and inspired!!! thanks so much for sharing your hard work and design!!! Now if it would just stop raining long enough around here I could get back at it !!!! again Thank you so much !!!!
Also I was wondering why you dont use double layer plastic with an inflation blower?? I am in michigan and thats what I plan to do, but what are the pros and cons of not using dbl layer plastic?? because I am all about saving some money if I dont need dbl layer of plastic and a blower!! lol
Try using solar powered roof fans located at both ends, the hotter it is, the faster they blow.
for example, check out the web site:
http://www.solatube.com/homeowner/solarstar.php?gclid=CMbi-vfcsp0CFVlM5QodMDk1jA
Thank you for posting this. I can’t wait to try it.
A friend brought me into her greenhouse the other day which is what inspired me to look here.
Ditto on the rain… crazy weather!
Thanks for the plans and comments. I thought I read somewhere the the gray PVC pipe was better because it is more UV resistant and perhaps less expensive. Thoughts?
I’m not sure about the UV resistance or expense of the grey pvc – it could be. I chose white for the sake of the plastic covering. Colored pipe would heat up more than white and perhaps damage the plastic.
Why did you decide to change the greenhouse ends to plywood? Oh and how did you secure the plastic at the ends of the greenhouse?
I chose wood ends for structural strength and the overall appearance. The plastic was secured with plain ol’ staples. I wasn’t sure that would do it, but it’s held up in some fierce winds so far. I think the key is having strong plastic.
I’e been looking for a plan like this for some time now and had drawn up one very simular but without the wooden ends. What kind of Plywood would you recomend (or sealant if that is plywood)? I know plywood won’t hold up well in the rain etc. Thanks Gene
I just used 3/8ths spruce plywood. I don’t expect a great long life span – probably no more than 5 – 7 years. But the ends of the plywood are covered so that water won’t get into them that way. I’m not sure if that helps you out much or not….
We live in NW Wisconsin and would love to try this. How early could we start planting? At what point would we need a heater? Sounds like our cold snap might last through March, even April. What have you found helpful? Thanks!
Hmmm, it tough to say when to start planting. The guidelines I use for myself are generally as follows: I typically presume my greenhouse can keep the temperature above freezing until about -7 with a little space heater I have. (This is all Celcius, by the way) Without the heater in an empty greenhouse – the greenhouse will certainly be warmer during the day when the sun shines on it, but at night both inside and outside will probably equal the same. All that to say, around here most gardens get planted around the third week of May. You might even pull it off occasionally around the first of May. But I plan to put things in my greenhouse about mid-April. As soon as the two week forecast shows nothing under -5, then I’ll start putting out my greenhouse plants. But it really depends on what size of heater you have (and how much money you want to spend to heat the place!)
I’ve read through the comments and am inspired to make a greenhouse for myself. Thanks. Here’s a thought about early planting and heating…how about stacked car tires. If you stack about three or four tires on top of each other and fill with dirt, you would have yourself a thermal planter. It’s on the same idea as black water barrels and thy are used to make “earthships”. Also, couldn’t you use black plastic over some of the clear plastic during winter months? I would like to know if anyone else has thought of this and tried it.
I have read that PVC outgasses chemicals that deteriorate the poly film. Is there some type of film you suggest to prevent this? Or are you painting your PVC before attaching the film? Or do you see deterioration along the PVC?
Thanks, working on a plan for my first greenhouse.
This is news to me. I have not painted my PVC, but to this point I haven’t noticed any deterioration either. The only “deterioration” issue is that my PVC pipes tend to get brittle with time. My mother-in-law has had the same greenhouse for two years and there doesn’t seem to be any poly deterioration where it contacts the pvc pipe.
I purchased the book from Eliot Coleman “The Winter Harvest Handbook” and he puts coldframes inside the hoophouse for early harvest. It’s worth to look into it. He has a webpage as well.
Where can I buy greenhouse poly in ontario? Will regular vapour barrier work?
Dave…Great looking hoophouse! Do you think the woven plastic be used with a regular greenhouse film (on the inside) and a blower for insulation?
If anyone else needs to save some money (like myself) Farmtek.com sells an 12 mil, “5.2 oz. Heavy-Duty All-Purpose Fabric – Clear” plastic. It is quite a bit more economical, especially for smaller sizes.
Also, OSB siding is much cheaper than plywood (at least around here). I have read that if the ends are sealed with silicon caulking (I think that is what was recommended), and the surfaces painted, it will last a very long time. The key was preventing water entry in the ends of the OSB.
Thanks for the comments. I agree – the double film with a blower would help a lot!
Sorry for the typos in the message #30….should have proof read before clicking the submit comment button. Anyway, I just wanted to add that the less expensive plastic fabric is also woven.
Hi, this is great! Writing from Albuquerque, New Mexico. Wondering about ventilation. How can I set up the sides to roll up when needed? And has anyone planted without raised beds inside the hoop house? Results? Advice?
i biult a hoop house. i am in alberta canada, the other day the winds were 61km gusts to 95km. the hoophouse survived ,miner damage my trees not so much i planted then last spring the wind pushed 2 trees over .the hoophouse was to hot i ran a 4ft wide strip of black poly down the center and it cools it off.
i am curious about the true hail proof-ness of this structure. i live in texas and not too many things here are hailproof. what did the hail do, slide off the sides? if it will break glass and dent your car i will certainty be impressed if it didnt bust through your plastic. can you give me some insight into this? i wanted to run some hardware cloth, which is really small mesh screening, the length of the greenhouse (like ur top rail) down about 4 feet to either stop or bust up the hail. well, those are my thoughts and questions. anxious to hear back. and thanks a lot for your response.
Cyndie, one hail storm we had broke car windows and mirrors, pounded hoods and roofs, stripped ALL the leaves off shrubs, made swiss cheese out of the siding on the house, and yet, bounced off the greenhouse plastic. I’m telling ya, it’s good stuff!
That hardware cloth may help. Is it like what you’d have on a screen door? Is it hail proof? I think you might be cutting down a lot of your light, but it’s hard to say. If it’s not too expensive, give it a try and see how it does. Then let us know!
Cyndie Lou,
Just throw a baseball as hard as you can at a bed sheet hanging on the clothesline. See what happens? The ball falls to the ground! A hail storm is the same thing. It is all just physics, action and reaction. The material absorbs the impact over time, albeit a short amount of it! As the material deflects from the blow it is slowing the velocity of the projectile. Something such as glass is not ductile enough to achieve this. It is brittle and inflexible and breaks from the dynamic impact of the hail. Something such as the steel hood of your car is not resilient enough and thick enough to handle the impact and becomes hammered, hence the imperativeness of hail insurance. 🙂 I intend to check out the super wonder plastic for my feature projects, perhaps, so should you?
Couple suggestions, for what its worth.
I’d build a hinged counterspace at each end of the frames for working on cuttings, etc.. Also, small shelves for equipment storage.
I’d like to incorporate plastic flaps using velcro for venting the hoophouse on the sides or ridge.
Difficult to explain. Easier to draw a diagram. But essentially, lap hoops with 3 widths of plastic running full length. Attach sides to wood strips running length of hoops. Overlap side pieces of plastic with top piece by several inches. Incorporate velcro along edges of overlaps. Peel back top and remove. To regulate amount of sunlight you could just tie up the center plastic with rope allowing recommended amount of opening between other pieces instead of removing completely. Possibly, replace center piece with shade cloth in Summer. Point is to make it versatile for your environmental or seasonal conditions. Also, mice, squirrels, and rabbits LOVE fresh food! Protect any ways inside, accordingly! Cats visiting the hoophouse can be a deterrent…Just my 2 cents…
Just found this thread while looking for info about reactions between pvc and poly. I have a 15×20 house built from 1 1/2 pvc conduit. Here in Augusta, GA we don’t have to worry about snow loads so the ribs are 5′ apart. In 1 1/2 years, I have covered it twice and it’s time to do it again. Tearing of the poly always occurs along the ribs. I presume that is a combination of pvc/poly reaction as well as heat build-up from the gray pipe. The poly actually sticks to the pvc after awhile, particularly in hot weather.
Anyway, this time I have purchased some felt tape made for greenhouses. It will be run along the top of the ribs to insulate the poly from the heat of the pvc, as well as keep the poly from touching the pvc.
Should know by late winter whether the poly lasts longer or not. Also, I have a 50% shade cloth to put over the house during the rest of the summer and fall.
That “5.2 oz. Heavy-Duty All-Purpose Fabric – Clear” from Farmtec…does that replace the normal greenhouse plastic covering? I ask because it seems as though the all-purpose fabric wouldn’t be waterproof…?
Would this concept be useful for putting a winter cover over a 18 ‘ round pool?? It seems that the leaves wouldn’t settle down inside and would be easier putting on and taking off a tarp.
I built a wood frame greenhouse one time and wanted to protect the plastic from the rough wood..i cut carpet strips and stapled them to the wood runners..worked great and the plastic wore out LONG before the carpet strips did.
I’m trying to build a shelter for a mini travel trailer I just purchased. The body of it is only 10′ long (13″ including tow bar) X 5′ 6″ wide X 6′ 6″ high. I was just going to make something like a lean-to with poly sheets, but this might work even better. Doesn’t need a door, just overlapping poly – actually want moisture to be able to escape with air moving through. I’m not worried about keeping it warm, just keeping excessive rain and snow off. I can store some firewood under too.
I’m very bad with geometry, so can someone figure out how long the pvc would have to be to give me 7′ high X 6′ 6″ wide? I’ll make it about 14′ from front to back. Thanks
slip two sets of metal shower curtain loops over rib on one end before putting on plastic , use extra plastic make a curtain to close off smaler section to heat in winter. 2 c
This is an 8 x 16′ and done pretty much like discussed. Doors cam open and closed. I built it around our orange tree.
[img]https://www.albertahomegardening.com/wp-content/uploads/2010/12/DSC09178.JPG[/img]
that looks great Curtis i cant wait to set mine up im about to move out of the busy town and out to the middle of nowhere i gotta say thanks Dave youve givin me heaps of ideas i’m going to post back when im done
has the 11 mil woven poly lasted on the pvc pipes? I hope to make a hoop house out of pvc pipes and am not sure just what cover I should use – thanks!
Trish, the 11 mil poly is still up with no issues!
That “5.2 oz. Heavy-Duty All-Purpose Fabric – Clear” from Farmtec…does that replace the normal greenhouse plastic covering? I ask because it seems as though the all-purpose fabric wouldn’t be waterproof…?…..also will it still hold the warm’th…
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.
[img]https://www.albertahomegardening.com/wp-content/uploads/2011/03/tomatoes.jpg[/img]
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.
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.
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]https://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