Hoop House Open Source Hub

As part of One Community’s four-phase strategy and global change methodology, we’ve created the following page for open source project-launch blueprinting affordable and large-scale hoop houses that will be constructed as part of our large-scale gardening strategy that, when combined with beginning the One Community food forest, is Phase I of the planting component of our food infrastructure. Phase II will be construction of larger and more permanent food structures. We will use hoop houses to expand both our early and late growing seasons by establishing seedlings earlier in the spring and growing a second fall crop of leafy greens. This will provide a more efficient, affordable, and effective production plan than simply growing outdoors and in the aquapinis and walipinis. Foods that will do well in hoop houses include potatoes, onions, beets, carrots, tomatoes, cabbage, etc. Any foods grown this way will also be accessions as part of our open source botanical garden model.

This open source hub includes the following sections:

• Related Pages
• What is a Hoop House
• Why Build Hoop Houses
• Walk-in Hoop House Construction and Costs
• Large-scale Ground-based Hoop House Construction and Costs
• Hoop House Planting and Harvesting
• Open Source Content to be Added Later
• Other Resources
• Summary
• FAQ

RELATED PAGES (Click icons for complete pages)

CLICK THESE ICONS TO JOIN US THROUGH SOCIAL MEDIA

 

WAYS TO CONTRIBUTE TO EVOLVING THIS SUSTAINABILITY COMPONENT WITH US

SUGGESTIONS | CONSULTING | MEMBERSHIP | OTHER OPTIONS

 

WHAT IS A HOOP HOUSE

A hoop house (also called a polytunnel or hoop greenhouse) is a greenhouse with a plastic roof wrapped over a flexible structure of hoops. The interior heats up because incoming solar radiation from the sun warms plants, soil, and other things inside the building faster than heat can escape the structure. The large hoops or bows can be made of metal, plastic pipe, or wood. The heavy greenhouse plastic “skin” is then stretched tight over the hoops and fastened to baseboards with strips of wood, metal, wire or even used irrigation tape and staples. Hoop houses are affordable, fast and cheap to build, and can extend a growing season by at least a month or more on each end. Click here for an extensive article on hoop houses if you’d like to read more.

Here’s a 60 second video on small hoop house construction for under $50:

WHY BUILD HOOP HOUSES

The goal with hoop houses is to add a couple months to any short growing season. In some places this will allow people to quickly begin food production while we are waiting for other larger Phase II food production structures to be built. We will use this page to open source share our evaluation of hoop houses as a growing option, how they work in our specific location, productivity and maintenance requirements, and related topics like manual venting needs, effects of weather, wildlife, etc.

Our initial objective is to construct eighteen 11′ wide x 90′ long x 8′ high hoop houses for:

• Seedling starts of warm-season crops (tomatoes, peppers, eggplant, etc.)
• In-ground growing of cool season greens (spinach, arugula, lettuce, etc.)

 

HOOP HOUSE CONSTRUCTION AND COST

CONSTRUCTION COSTS

Here is a complete materials list and costs for an individually applicable 11′ wide x 15′ long x 8′ high walk-in hoop house design. This design can be enlarged or decreased by simply adding or removing hoops and associated materials. We will enlarge them (see below) to 90′ long. Be certain to have accurate measurements for determining plastic size before ordering!*** Prices are current as of January 2014.

MATERIAL	DESCRIPTION	PRICE	QTY/House	TOTAL
PVC	20′x3/4″ PVC schedule 40 plumbing pipe	$4.57	6	$27.42
Gray Conduit*	10’x1 Â¼Ã¢â’¬ gray conduit schedule 80*	$5.85	12	$70.20
Wood Stabilizers	1x6x8′ pressure treated (cut to 1×3’s)	$8.97	6	$53.82
Wood	2Ô4′ stud (cut into 1×2’s)	$2.25	3	$6.75
Wood	1x4x12′ pressure treated	$8.77	2	$17.54
Wood	2x4x16′ (cut into 2x2s)	$7.06	1	$7.06
Posts	8′ Steel “T” fence post	$5.77	4	$23.08
Rebar Anchors	20’x½â€ (cut as needed – based on soil consistency)	$7.10	1	$7.10
Ties	8″ plastic zip ties – 100	$8.97	1	$8.97
Screws	1 ¼â€ x  Â 5lb drywall screws	$21.97	1	$21.97
Wire for X Braces	16 gauge galvanized utility wire – 25′ roll	$6.47	1	$6.47
Staples	3/8″ t-50 staples ” 1250/pack	$3.22	1	$3.22
Plastic***	6 mm IRAD poly film 25’x35′ sheet	$150.00	1	$150.00
Plywood	For reinforcements… scrounged	–	–	–
		TOTAL/HOUSE		$376.18
		BUDGETED TOTAL**		$500.00

* Gray conduit is a sturdier option and is also UV resistant, resulting in extended longevity over standard white PVC. This is beneficial because PVC is susceptible to brittleness and breakage over time due to UV degradation. Prices include sizes of 1″, 1 ¼”: and 1 ½”. Because it comes in 10′ lengths instead of 20′ lengths, use the bell end of one of the lengths to join the two 10′ lengths for a single 20′ piece. We will likely use 1″ or 1 ¼” for the hoop bows.

** For budgeting $500.00/hoop house, no shipping has been included as we will probably pick up locally. The one exception would be for IRAD film. IRAD film will be shipped and shipping price is included in sheet pricing. The budgeting cushion is for other missed expenses and taxes for components other than IRAD film (No tax has been assessed by our IRAD seller) and allows us to expand each house on-site (if deemed necessary) while remaining within our budget parameters.

*** Be sure to check and double check that your plastic size is correct. Cutting fees can range from $12-$20/cut. Cut your own on-site from a roll to avoid this charge. Here is one way to calculate the size of plastic required:

Width of plastic is determined by these hoop house structural measurements:  Width + Height + 2′ (round to standard width size – always good to have more than not enough)

Using this formula our 11′ wide x 15′ long x 8′ high hoop houses would require a plastic width of 21′ (11+8+2 = 21′). So we would buy a 22′ wide plastic roll.

Length of plastic is determined by these hoop house structural measurements:  Length + Height + Height + 2′ (assuming the cover is bottom to bottom including both end walls)

Using this formula our 11′ wide x 15′ long x 8′ high hoop houses would require a plastic length  of 35′ (15+8+8+2 = 33′). So we are calculating a 35′ length. Thus, one sheet of 22’x35′ IRAD poly film ($150) will cover one hoop house this size and we are ordering two 22′ x 105′ rolls that will provide for 3 of our starter houses per each roll, so enough for 6 hoop houses total. 

This formula will give you some leeway with the plastic; yes there will be some leftovers, but if you are short, you will have to reorder or downsize your hoop house. Also, be careful when using online calculators as they generally provide surface area measurements and may or may not include built-in leeway, and you do want at least one foot excess on all sides so you can stretch the plastic taut.

MORE HOOP HOUSE PLASTIC INFORMATION

Here’s a link talking about the best plastics for greenhouses: Click Here. 

Based on our own research, UV-treated polyethylene (or IR film which greatly reduces or eliminates interior condensation and is about $0.02 more per square foot over standard UV treated polyethylene film) is our recommended choice for hoop houses due to durability and eliminating the yearly labor replacement efforts of non-UV plastic. The UV-treated is guaranteed by most wholesalers for 4 years, some stating that many consumers report a longevity of 6-7 years. We have not substantiated this claim and will determine its true longevity over time. It can be ordered in rolls from 6′-64′ wide. Most companies carry rolls 100′ in length or more and some cut to whatever your desired length, 1000′ or more. When ordering in large quantities, the square foot price is $0.10 – $0.12 cents/sq. ft. Prices are quoted both by the square foot and lineal foot. Some distributors will offer dealer pricing which will decrease the overall price. Most large sellers seem to have only a fractional difference in price. Shipping is variable, 15-20% of the cost is a guideline but exact rates can be determined at the time of your order placement. Some offer prepaid shipment over 3000 lbs. Small orders under 21′ widths are generally shipped UPS while 21′ widths and larger are by semi-trucks. Global shipping is done by many. Six mil polyethylene is also referred to as 150 micron poly, depending on your geographic location. Some websites provide prices but due to fluctuations, you will have to order via phone for up-to-date pricing.

Though there are numerous suppliers worldwide, here are four that we researched:

Gempler’s: Website Â ::  Customer Service: (800) 382-8473  ::  Technical Support: 800-874-4755
FarmTex: Website  ::  (800) 327-6835
U.S. Global Resources: Website Â ::  (206) 722-3999
Gothic Arch Greenhouses: Website Â ::  (800) 531-4769

No matter who you contact, check for the closest dealer to minimize shipping costs. Order larger quantities for better price breaks.

We also researched 6mm polycarbonate from China that claims to have a 10 year warranty. We spoke to several US vendors and they said this new flexible polycarbonate plastic is not as durable as stated. We’re not sure if this is accurate or marketing for their advantage.

ONE COMMUNITY APPLICATION/EXPANSION

One Community will utilize the above hoop house format and adding to the length so the hoop houses will be 11′ wide, 90′ long, and 8′ in height with 2 adjacent 90′ structures in a 180′ row. We will construct 18 greenhouses that will each provide 1530 sq. ft. (11′ x 90′) of growing space. 1530 sq. ft. x 18 houses = 27,540 sq. ft. under plastic (.63 acres). There will be a 3′ wide center aisle and two 3′ side aisles with two 4′ beds on each side of the center aisle. Total estimated cost is $54,000.00.

By connecting six of the 15′ long hoop houses into a single 90′ structure, we eliminate the cost of 10 exterior walls (20/row – 180 walls total) in Hoop House Installation Phase 1 construction. This equates to eliminating 15,840 sq ft of plastic (one wall is 11′ wide x 8′ high = 88 sq ft/wall x 180 walls =  15,840 sq ft) along with additional framing lumber costs.

Exact row spacing between the 180′ structures will be determined at time of construction (as the specific site allows), but ideally we will attempt 20′ spacing between each hoop house row. 31′ (20′ of spacing + 11′ of hoop house) x 9 rows = 279 feet. We will determine the exact spacing by using 3-D Sketchup location-mockups that will allow us to run specific sun simulations for our latitude and longitude. Our intial space-needs-projections are for a plot of land that is 300′ x 200’= 60,000 sq. ft. (1.38 acres for the total Hoop House Installation Phase 1). Should we add a Hoop House Installation Phase 2, we will account for additional space to serve that requirement.

In addition to the hoop houses we will plant approximately 2-3 acres of outdoor gardens; with the hoop houses, open gardens, and orchard all fenced to minimize loss to wildlife.

 

HOOP HOUSE PLANTING AND HARVESTING

We have budgeted to purchase food as needed for the first 2 years but our goal is to demonstrate food self-sufficiency by the end of the first year. When combined with milk, eggs, and meat from ethical animal husbandry, we project we can feed all 50 of the initial building team plus an additional 50 interns/scholarship recipients by the end of the first year. By the second year we expect to begin work on the additional food structures while continuing to increase our annual yield from large-scale gardening strategy and expansion and development of the the One Community food forest. Our first-year experience with the hoop houses and gardening will build the foundation for production from the second year forward to meet any additional food needs for ourselves and all our guests. The quantities grown are limited only by our labor input and our ability to both ward off and allow hungry critters their fair share.

Our intention with these hoop houses and our first outdoor gardens is to over-plant and grow as much as possible so we can preserve much of it by drying, freezing, canning, and pickling for use throughout the winter season. Any varieties of fruit can be dried/canned and easily stored while the majority of our vegetable production can be frozen, canned and held over in an earthbag root cellar. Some root crops can be stored in-ground and utilized throughout the winter when mulched heavily. This last option is best accomplished in regions of heavy snowfall while simultaneously mulching with deep layers of leaves; as snow acts as an insulator, preventing the crops from freezing while maintaining a crisp fresh taste. The leaves can be bagged (to prevent the wind from scattering them) and laid directly over root crops with the insulating snow acting as additional protection. If you do not have adequate snow coverage during the winter, this method will be less effective; the more snow and cold you have the more appropriately this method demonstrates its effectiveness. Each year we will conduct a community social event during the harvest season to involve everyone in this hands-on process. With our larger growing structures, hoop houses, extensive outdoor gardens, and multiple preservation options, our fruit and vegetable needs will provide us an abundance of wholesome, fresh, nutritious food choices year-round.

HERE ARE THE PLANTING MAPS FOR THESE STRUCTURES

CLICK HERE FOR OVER 100 HEIRLOOM SEED SUPPLIERS

 

OPEN SOURCE CONTENT TO BE ADDED LATER

A huge additional volume of open source information will be added to this page as we build One Community. We will also update all the information here with exact numbers and details from our experience. Open source resources that will be added to this page as we build include:

• Specific building diagrams and step-by-step instructions
• Time-lapse and instructional videos detailing each component
• Ongoing results of our food production experience and yields
• Ongoing results of our experience maintaining and upgrading these structures
• Specific details about how these structures work in conjunction with the rest of the One Community food infrastructure, our global change methodology, and the One Community teacher/demonstration hub goals 

 

RESOURCES

Here is a list of additional greenhouse and hoop house related resources:

• Open Source Large-scale Gardening Hub
• Open Source Botanical Garden Creation Hub
• Open Source Large-scale Soil Amendment Hub
• Canning, Drying, Seed Saving, Planting Planning etc. resources
• 100+ Heirloom, Organic, and Other Seed Suppliers/Providers
• DIY Hoop House Videos with Building Instructions and Materials Lists
• PDF: Full materials list and building instructions for an arched pvc greenhouse
• Greenhouses pinterest page
• Article: “DIY Projects: 4 Ways to Heat a Greenhouse”
• PVC Fittings, Snap Clamp Connectors & Furniture PVC Pipe Information and Purchasing
• Furniture Grade PVC DIY Plans and Pictures for Greenhouses and Related PVC Ideas
• 10 Free Greenhouse/Hoop House Plans
• Five DIY Sprinkler Systems
• Article: The Benefits and Drawbacks of a PVC Greenhouse Frame
• How to Build a $50 Greenhouse
• Build an Easy 5 x 5 Home Greenhouse for under $25
• Tutorial: “DIY Wood Greenhouses – Polycarbonate Greenhouses – Hoop Houses”
• Suggest an addition to this section by clicking here

Three hoop house videos with a wealth of hoop house information we think most people will find useful:

Here are two more too:

 

SUMMARY

The One Community food infrastructure is part of our botanical garden model and purposed to demonstrate food quality, diversity, and self-sufficiency. Our initial food infrastructure consists of open source sharing all our large-scale gardening, food forest development, 6 different aquapini and walipini structures, and hoop houses—affordable, fast and cheap to build, and capable of extending a growing season by at least a month on each end. Hoop houses will be used year-round for early seedling starts and seasonal warm and cold-weather crops to help us maximize food production. We will preserve all additional food possible through drying, freezing, canning, and pickling. Hoop houses combined with large-scale gardening, ethical animal husbandry, what we will grow in the aquapini and walipini structures, and a property-wide food forest are capable of producing sufficient food to feed One Community and all our visitors with a diversity and level of nutrition far beyond anything found in a typical grocery store.

 

FREQUENTLY ANSWERED QUESTIONS

Q: What is One Community’s stance on pesticides, herbicides, and fungicides?

If it is not safe to eat, we will not spray it on our food.

Q: Why will the crop plants in the hoop houses be part of the botanical garden model?

As we develop our food resources over time, the open source botanical garden model is important in allowing us to know the breeding lines that go into developing crops that are well adapted to the site. Accession records allow us to know that if we selected variety X from source A for early maturation or other traits for several generations, then variety X sub 6 exhibits amazing properties and becomes “OC Purple Giant” (or some other name) then we have the needed tracking and records to know that we can take the same starting germplasm, selected the same way, and get similar results. Without careful records, this is impossible.

Also, the sheer volume of varieties that will eventually grow on the site would be impossible to manage without some system of reference. We will easily grow many dozens, or even hundreds of dozens of different crops. Many of the regional, national, and international crop centers around the world that we will source from have enormous collections and using their accession records enable us to know a great deal about the material they are holding, so as to make better selections when requesting that material. We would like to add to this, and accurate record keeping on our part is a logical extension of our open source model since we can share both the source data from the original institution, collector, or farmer/gardener AND pass along our observations of the materials performance, vulnerabilities, hardiness, taste, and cooking characteristics, etc., that may not be available originally. Just as with the “OC Purple Giant,” accession also becomes especially beneficial for us and others when “that bell pepper from Romania shows complete resistance to Colorado potato beetle!” or something similar.