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20 x 20 High Tunnel Greenhouse

High Tunnel Covering?*

Sidewall Height (Solascrim)?*

Sidewall Height (Solexx)?*

Professional Install or DIY Kit (5' Solascrim)?*

Professional Install or DIY Kit (6' Solascrim)?*

Professional Install or DIY Kit (7' Solascrim)?*

Professional Install or DIY Kit (5' Solexx)?*

Professional Install or DIY Kit (6' Solexx)?*

Professional Install or DIY Kit (7' Solexx)?*

Roll Up Side

Total: $0.00

Features

    • Pre-drilled holes in frame makes assembly easy and simple.
    • No foundation or footer required
    • Length can be added to in 4′ increments.
    • 115+ mph wind resistance; 70+ psf snow resistance
    • Maintenance free once setup is complete
    • 10 year frame warranty on all greenhouses. 10 year cover warranty for Solexx, 4 year for polyethylene.
    • Highly customizable for vents, hanging benches, and other additions.
Length Options
For SolaScrim units:
$600 addition per 4′ increment increase for DIY kits. $650 addition per 4′ increment increase for installs.
For Solexx units:
$850 addition per 4′ increment increase for DIY kits. $925 addition per 4′ increment increase for installs.
Specifications
  • Width x Length 
  • All galvanized steel or aluminum frame and hardware
  • Can come with or without roll up sides
  • Doors and Baseboards are not included in DIY kit pricing as they cost more to ship than source locally.
Assembly

Check out our DIY instructions on youtube!

Typical assembly time is 20 to 40 man hours, depending on the structure’s size. 

Details
  1. Terms and Conditions
  2. Warranty

20 x 20 High Tunnel Greenhouse

The largest in the series, the 20 x 20 High Tunnel Greenhouse is designed for ambitious gardening endeavors, providing extensive space for a wide variety of plants. This tunnel is perfect for those looking to maximize their gardening potential, offering robust protection against the elements and optimal light penetration for year-round cultivation. All of our greenhouses can be extended in 4′ increments.

Product Specifications

  • High Tunnel Roll-Up Sides

    • Tall Vertical Sidewalls
      All of our units have vertical sidewalls at least 5’ high to maximize headroom and passive ventilation capacity with our standard roll-up sides.
    • Hip Channel
      Double Wire Channel Aluminum Extrusion; allows top and side poly to be serviced independently; can fit multiple layers of poly for inflated top poly system, or layers of poly and shade cloth if desired.
    • Base Board
      Pressure Treated Lumber; our kits come standard with 2” x 6”s; a taller base board (ex. 2” x 10”) is available upon request; can be sourced locally on DIY kits to save shipping cost.
    • Wind Panels
      10mil SolaScrim™ comes standard; these help bolster the structure against high wind loads; units shorter than 16’ may want to forego these if maximum ventilation is a priority, and price will be waived, if so; they can always be added later!
    • Simple Crank Handle Design
      Easy, functional, low tech on purpose; can be upgraded to a geared-ratio operator with internal brake that increases ease of operation on large units (not necessary for most smaller units).
    • Anti-Billow Rope & EZ Snap Hooks
      ¼” Solid Braid Polyester anti-billow rope is naturally UV resistant; paired with EZ Snap Hooks placed in the hip channel and screwed into the base board, the anti-billow ropes help hold the roll up sides in place and prevent excessive billowing, which could lead to damage of the poly. EZ Snap Hooks also provide another way to attach shade cloth if desired.
    • Wiggle Wire
      Standard width and 4’ lengths make it easy to handle; made of stainless steel for a corrosion-free lifetime of performance.

  • High Tunnel End Walls

    • End Wall Ground Posts
      1.66” OD x .060” galv. steel tube; 4’ long, driven 3’ into ground.
    • All End Wall Framing
      2″ Square x .060” thick galv. steel tube; all our kits come standard with end wall framing and accepts a 36” x 80” personnel door on both ends.
    • Personnel Door
      (1) 36″ x 80″ ¾ Glass Storm Door comes standard with installations; a second door can be added; for DIY kit, these can be sourced locally to reduce shipping costs and chances of damage in shipping; we can also make roll-up end doors if a larger opening is desired.
    • Single Wire Channel
      This channel is deep enough to accept multiple layers of poly; it is placed on the end bows, across the bottom of the end wall frame, and around doors to securely attach poly using wiggle wire and allow for easy future servicing.
    • Wiggle Wire
      Standard width and 4’ lengths make it easy to handle; made of stainless steel for a corrosion-free lifetime of performance.
    • End Wall Covering (Solexx)
      Solexx tops the charts for greenhouse covering options due to its superior performance, which means high heat retention and less temperature fluctuation for your plants and lower heating bills for you!
    • End Wall Covering (Americover)
      10mil Solascrim™ comes as the standard option with all our kits.

  • High Tunnel Framing

    • Ground Post Anchors
      1.90″ OD x .060” thick galv. steel tube; 4’ long, driven 3’ into ground; alternative anchoring methods available upon request.
    • Bows
      1.66″ OD x .110” thick galv. steel tube; 4’ spacing between bows; these slide into the ground posts; nearly twice as thick as the .060” tubing most companies use!
    • Rafters
      1.66” OD x .060” galv. steel tube; comes standard on every interior bow for added strength in wind and snow.
    • Purlins
      1.315″ OD x .060” thick galv. steel tube; 1 on peak, 1 per side, 3 total; all full length of structure.
    • Corner Braces
      1.66” OD x .060” galv. steel tube; 5′ long; 1 per corner, 4 total.
    • Peak Braces
      1.66” OD x .060” galv. steel tube; 5′ long; 2 per end, 4 total.

We simplify the process of choosing the right structural features by pre-selecting the optimal roof shape, bracing, and truss supports tailored to Arizona’s unique weather conditions. This approach saves our customers valuable time and effort, while also avoiding the additional costs of customizing these essential components. Our goal is to offer complete peace of mind, knowing that even our standard kits are engineered to withstand the challenges of the environment. If you are interested in seeing how the kits work, check out our DIY instructions on YouTube.

Product Warranty
Return Policy

Choosing the Right Cover

Solexx

Solexx is the more impressive sibling of the widely used twin-wall polycarbonate. It boasts a higher insulative R value (2.3) than polycarbonate (1.5), does not yellow or become brittle over time, and is 100% shatterproof. 

The material can hold up to 130 lbs per square foot for sustained periods of time, making it the right choice for those living in snow-prone areas. 

While the upfront cost of Solexx is higher than 10 mil SolaScrim, it does come with a 10 year warranty and a likelihood to last a good deal longer. 

It is extremely easy to attach to our structure as we pre-drill all of the holes in the frame’s bows. In assembly, you will have to use self-tapping screws only on the aluminum straps which run lengthwise. 

Other features of Solexx are that it diffuses light in a full spectrum manner, which encourages rich, compact plant growth, speeding up the journey to market. It is made of high-density polyethylene (HDPE) and integrates UV inhibitors throughout, ensuring durable sun protection that resists scratching and wear. 

10 mil SolaScrim

Our 10 mil SolaScrim Polyethylene is one of the most durable poly covers out there. It comes with woven string reinforcements which will prevent a tear from spreading beyond the square of string it occupies. 

This is a great option for those who only plan to use their high tunnel as a season extender, not as a year round grow space. 

While the poly may not provide the insulation needed for winter growing, it will still stand up to the storms and winds for those living in inclement weather areas. 

We match the manufacturer’s warranty of 4 years, and can also supply repair tape if anything wears down after that. 

Industry wide practice for high tunnel coverings is to use a 6 mil clear polyethylene. Here is a video we made to compare the two.

Frequently Asked Questions

What tools do I need to assemble my greenhouse?

At the minimum, you will need:

  • Tape Measure
  • Sledgehammer
  • Stakes
  • Stringline
  • Hacksaw
  • String Level
  • Drill or Driver
  • 5/16” Hex Driver Bit
  • 3/8″ Hex Driver Bit
  • 14mm or 9/16” Wrench/Socket
  • Ladders
  • Box cutter and wire cutters

                    Can I put a foundation in if I want to?

                    Absolutely. Our ground posts can be mounted onto concrete using a simple post adapter. Contact us for more details if you are interested in this method.

                    How does it ship to me?

                    We ship all of our products using LTL freight. We bundle the entire product into a custom pallet, which will arrive to your location using a lift gate truck.

                    Where can I buy the door and baseboards?

                    We do not send the door or baseboards because it would not be cost effective to you. Our door openings are made for any 36″ wide door, and the heights can be selected by the assembler. A typical storm door from Home Depot (found here) and treated wood for the baseboards will do the trick, but it is entirely up to you! 

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                    Still Not Fully Convinced?

                    Unsure if you’re ready to begin your journey towards an abundant harvests? If you’re not quite convinced or have any questions, we’re here to help. Reach out to us today to learn more about our High Tunnel Greenhouses and innovative growing solutions. Together, we can achieve a greener, healthier future.
                    Steady Harvest – Committed to Supporting Your Growth!
                    Contact Us Online
                    Or Call – 928-814-6371
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