There are as many different types and styles of hoophouses as there are farms, farmers, gardeners and homesteaders. 

Houses can be over 100 feet long and 30 feet wide, or as little as 12’ x 24’. Endwalls can be plywood or poly, wood-framed or steel. Covers can be the standard one layer 6 mil, 4-year, UV-treated poly, or two layers, UV and IR (infrared), inflated; or an alternative like SolaWrap. You can have doors wide enough for people or tractors, passive vents at the gable end peaks, roll-up sides that are manual or automatic, and that’s just the beginning...

Bottom line: you have a lot of decisions to make when thinking about your new high tunnel structure. Each decision will alter the timeframe, materials required, cost, etc. It is essential that you take your time to do as much research and planning as you need, so you know exactly what you're looking to build.

Below is a basic overview of things you'll want to be thinking about. Take a spin through our Gallery, to see a variety of different design options and considerations. 

We have created a Greenhouse Design Worksheet to help you work out all the details of your project. Print the worksheet, read through the design ideas and features laid out on this page, and create the ideal outline for your project and budget. 

 

Vine Ripe is always available to help you work through all the your possible options. 

give us a shout, and we'll get started. 


Manufacturer

There are dozens of different high tunnel hoophouse manufacturers out there, each with their own sales pitch, pros, and cons. Probably the three most common structures you'll see around New England are from the three manufacturers below. If you have very specific growing or construction requirements, you'll want to contact the manufacturers directly for more insights into the specifics of their products.

All three are perfectly suited to virtually any agricultural purpose including plant production, seed starting, livestock housing, and storage. All are delivered as a complete kit depending on your needs, can be heated or unheated, come in a variety of widths and lengths, and can be modified or adapted to as needed. All are designed for heavy snow and wind, and can be used for four-season growing.

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Ledgewood

Easy to build and maintain, Ledgewood houses come in 1.6" - 1.9" diameter galvanized steel frames available in four foot increments of length, and up to 30 feet wide. Ledgewood houses generally employ lumber hips to secure cover poly, and wood-framed endwalls, and they provide some of the best customer service in the business.

Harnois

Harnois out of Canada uses an "ovaltech" galvanized steel tubing for framing that they claim is much stronger than the typical cylindrical tubing. Available in widths 21.5' - 42', Harnois houses are taller, wider, generally more robust structures that can be a little more challenging and considerably more time-consuming to build.

Rimol

Rimol houses are very similar in design to the Ledgewood frame with some modifications around purlin and hip attachment hardware that is a bit more cumbersome, but just as effective in the end. Rimol houses include wirelock to secure the roof and end wall poly, and can include steel framing and polycarbonate for endwalls. 


Endwalls

Framing & Covering - Endwalls can be wood-framed, steel-framed, covered in poly, plywood or other lumber, or polycarbonate sheets. Some manufacturers may recommend one over another: poly endwalls need to be repaired and replaced on occasion, plywood can warp and rot over time, and doesn't let any light in, while polycarbonate is more expensive but lasts much longer. For wood-framed endwalls, I generally recommend 2x4 rough sewn hemlock from a local sawmill, but you could go with whatever you prefer.

Attachments - You should also consider how you want to attach your endwall framing to your endbow. Ledgewood houses supply steel pipe strap that wraps around the bow and screws to lumber framing, while Rimol and Harnois houses use different steel bracket styles. I personally recommend steel endwall framing brackets that can be ordered from an outside supplier, which are considerably sturdier.

Doors & Vents -  Lastly you'll want to consider doors and vents. Whatever your heart desires, we can make it happen. Louvers, fans, passive windows, double doors, single person doors, sliding doors, roll-up doors, etc. Depending on your needs, doors and vents can be framed in any configuration. You can buy prefabricated doors and vents, or build your own. Check out the Gallery for more images.

Endwall Sills - Steel-framed endwalls generally have studs set into the ground, while lumber-framed endwalls require a sill to build your framing on. Some sills are set directly on the ground, on crushed stone, or cinder blocks. Some are a single layer 2x4, while others are more robust. I personally like 2 stacked layers of 2x6 rough sewn hemlock on cinder blocks for stability and levelness. Images of what that looks like can be found in the Gallery.

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Covering (Glazing)

Covers can be the standard one layer 6 mil, 4-year, UV-treated poly, or two layers, UVA clear and IR (infrared), inflated; or an alternative like woven poly or SolaWrap. Traditional greenhouse poly is generally good for four to five years as it degrades a bit and becomes opaque over time. It's obviously susceptible to tears and punctures if mistreated, though it's easy to patch, and fairly easy to maintain and replace.

Bees need ultraviolet (UV) light to navigate. If a grower uses bees to pollinate plants in the greenhouse, purchasing a film that allows some of the ultraviolet light energy spectrum to pass through may be important. Otherwise, UV blocking film is said to reduce whiteflies, thrips, aphids and other insects. It can also control some fungal diseases. Infrared (IR) additives provide light diffusion, absorb and re-radiate infrared heat back down to the crop during the evening hours, reportedly saving as much as 30% on heating costs.

Double layer inflated poly requires power for a small blower fan, can reduce heat loss at night by nearly 40 percent, and can assist in shedding snow in winter. Double layers generally include the IR poly on the inside and the UVA clear poly on the outside layer.

Alternative coverings like woven poly or SolaWrap are considerably stronger and longer lasting, but also much more expensive and reduce light penetration by at least some small degree. For more information you should contact the manufacturers of these products directly.

Double layer inflated 6-mil poly shedding snow in winter.

Double layer inflated 6-mil poly shedding snow in winter.

"Woven Poly is strong, durable, and resistant to heat, extreme weather and tearing. The toughness is due to the weave, the thickness, and the UV stabilizer." (www.northerngreenhouse.com)

"Woven Poly is strong, durable, and resistant to heat, extreme weather and tearing. The toughness is due to the weave, the thickness, and the UV stabilizer." (www.northerngreenhouse.com)

Traditional, single layer 6-mil poly with sides rolled up.

Traditional, single layer 6-mil poly with sides rolled up.

"SolaWrap greenhouse film saves energy, offers UV protection and has unmatched durability with transparency that extends the growing season. The unique bubble design provide strength, longevity, and better growing." (www.solawrapfilms.com)

"SolaWrap greenhouse film saves energy, offers UV protection and has unmatched durability with transparency that extends the growing season. The unique bubble design provide strength, longevity, and better growing." (www.solawrapfilms.com)


Hips, Baseboards, Curtains, & Roll-Up Sides

Hipboards - There are typically two types of hipboard setups depending on what you're looking to do. Hips can be wood, and use a wood batten system to attach the poly, or they can be single or double wirelock channel and "wiggle-wire." They could also be some combination of the two, if you feel like being creative. 

If you're considering poly endwalls, you'll also want to consider wirelock channel for up and over your endbows. This channel will carry both your endwall and cover poly in the same channel. Plywood or polycarbonate endwalls can also have wirelock on the endbows, but you'll want to specific endbow wirelock channel that has a flange that hangs over your endwall material. Wirelock is easy to install, never rots, and is easy to remove and replace when it's time to replace your poly. That said, it's also more expensive. 

Baseboards - All houses require baseboards both for structural stability, and for somewhere to either attach your cover poly, or to roll your sides down to. Baseboards will rot and need replacing over time. I generally recommend 1x10 rough sewn hemlock. We can use 2x10 as well, but it's considerably heavier and a little bit overkill. For that matter, you can use dimensional pine as well, but this generally rots quicker. Note: most states don't allow the use of pressure-treated lumber on certified organic farms, if that lumber is going to come into contact with the ground. 

Roll-Up Sides - Most hoophouses these days are employing roll-up sides as a primary feature for optimal ventilation. Roll-up sides can either be manual or automatic. The automatic are connected to a thermostat and open and close on their own throughout the day trying to maintain whatever mean temperature you set it to. Manual roll-up sides require a little more work, but they're far less expensive. There are hand crank gearbox, and hand-over-hand type manual options as well, that come standard with most houses. The Harnois houses come with the crank, while the Ledgewood and Rimol each use a slightly different hand-over-hand style.

Curtains - Only the Harnois houses come with an established curtain option. A poly curtain is attached to the baseboard along each side, and goes up about 16-18" where it is attached to a wire running the length of the house. This curtain allows to not roll the roll-up side all the way down to the baseboard to create a seal, but just enough so it is over the curtain by 6" or so. Not rolling the side to the ground also means your roll-up side doesn't necessarily get buried in snow in the winter, though snow does pile up, of course. The curtain also provides some additional protection from colder breezes creeping in under roll-up sides potentially damaging young or sensitive plants.

Double wirelock channel at the hip.

Double wirelock channel at the hip.

Hand-over-hand roll-up side from Ledgewood.

Hand-over-hand roll-up side from Ledgewood.

2x4 hipboard and batten attachment system.

2x4 hipboard and batten attachment system.

Gearbox style crank roll-up side mechanism from Harnois.

Gearbox style crank roll-up side mechanism from Harnois.

1x10 hemlock baseboards and 2x4 hemlock hipboards.

1x10 hemlock baseboards and 2x4 hemlock hipboards.

Curtain installation on an Harnois greenhouse.

Curtain installation on an Harnois greenhouse.

Single wirelock channel on the endbow.

Single wirelock channel on the endbow.

2x4 hipbaord and batten system before poly installation.

2x4 hipbaord and batten system before poly installation.


Site & Orientation

 
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Orientation - You'll be looking to get the most sun year-round on your hoophouse, so as a general rule, and if your site can accommodate it, at northern latitudes (above 40 degrees), an east-west orientation works best to catch maximum light the length of the south side during winter. 

You should also consider the prevailing direction of the wind. Wind blowing over a greenhouse is much like wind going over the wing of an airplane wing. Building your house broadside to prevailing winds should be avoided if possible.

You'll also want to consider shadows and shade from trees, hills, and buildings, including the shadows one greenhouse may cast on another one next to it. If possible, it's recommended that you locate your greenhouse at a distance equal to at least twice the height of any potential shade source.

Site - You'll clearly want to consider where you have optimal soils when you're thinking about your site, but you should also consider proximity to reliable water and power, ease of accessibility and snow removal in winter, and the slope of the land. As level a site as possible is always best, and reduces your site preparation costs and requirements. A slightly sloping site allows for better drainage, as does a slightly raised site. Sites in depressions or valleys are likely to flood seasonally.

Make sure you're also paying attention to property lines, town right-of-ways, wetlands, and anything else that may impact how you choose your site.

A “well-prepared” hoophouse construction site will be:

  • Free of any substantial stones or rock.

  • Away from any prominent ledge or other solid substrate that may interfere with

    construction.

  • At least 15’ away from any other structure.

  • Recently mown and free of any substantial weed or other growth

  • Free of any prepared beds or crop planting.

  • Level graded – Perfectly level is the goal, but if there has to be a slope, you should aim for no

    more than 1% over the width (3” - 4” over 30’), or 2% over the length (2’ over 96’).

  • As dry as possible. No pooling mud or water. All necessary swales or site work necessary to

    direct water away from the site successfully completed before construction.

  • If your site requires the adding of material to build the site up, the prepared site should be a

    minimum of 6’ wider and longer than the footprint your hoophouse frame requires, and

    built of substantial, clean soil. Plan to seed around any sloped sides to help prevent erosion.

  • Have reliable, safe access for a truck.


Other Details

There are a ton of add-ons and details you can consider adding to your greenhouse project including heaters, irrigation, cooling, shelving, plant support, insect barriers, and more. There are couple suppliers I recommend for additional parts: Nolt's Produce Supplies and Griffin Greenhouse Supply. While there are specific features that come with or are available from each manufacturer, keep in mind we can pretty much add any feature or detail to any style house.

Greenhouse Shelf