1.What is a HighTunnel?
A Hightunnel is a solar heated greenhouse 'Usually' with no electrical or automated ventilation that is used to extend the crop production season for many horticulture crops. Crops that are produced within high tunnels are grown in the ground or in raised beds with drip irrigation. Greenhouses are heated systems that have foundations and are energy dependent whereas a Hightunnel utilizes Passive Solar. 2. Do I need to have a building permit for my HighTunnel?
High tunnels are considered to be impermanent structures and protected under the "Right to Farm Act." Nevada County has determined that no permit is needed for farmers installing a Hightunnel.
2. How does a low tunnel differ from a HighTunnel?
In a nutshell, you can stand upright in even an inexpensive high tunnel, but low tunnels are too short. Basically, low tunnels can be constructed by placing wire hoops, spaced 3 to 4’ apart and about 1.5’ high at the apex, over a row of crop to provide additional protection from the cold. A new practice that has shown success is to place a low-tunnel inside of a Hightunnel.
3. Where should I place a Hightunnel on my farm?
A Hightunnel should be placed on a level, well-drained, accessible site. BUT, many choose to build their Hightunnels on a slope or grade.
4. Should I grow vegetables in a Greenhouse or a Hightunnel?
Input costs for Greenhouse vegetable production are significantly higher relative to Hightunnel vegetable production. Greenhouses cost approximately $6-$12 sq ft or almost five times the cost of a Hightunnel.
10. What is the optimal orientation for a high tunnel?
Unlike greenhouses, orienting a High-tunnel for sunlight is not as crucial as long as the the Hightunnel gets ample sun. Although having the long side facing south is best if you are going to"force Flowering". In a windy location a Hightunnel should be oriented in a direction that faces the Endwall toward the prevailing winds


Remember, all ventilation is manual, or passive solar- so you depend on the wind to ventilate your house. In the Foothills, our winds are predominantly from the North -Northwest. Thus, for spring tomato production, we find an North-South orientation to be optimal.

Grizzly Hill Greenhouses offers a site consulation- because your sites' needs may be unique.

8. Can a hightunnel be movable?
Yes. One of the primary objectives of a high tunnel is to expand the harvest
period. our Cold Frames are the best solutions for building a movable system. However, movable Hightunnels are moved on to existing plots of land to accelerate growth or extend the growing season for that crop. However, relative to stationary Hightunnels, they are less airtight. Consult Eliot Coleman’s Winter Harvest Manual for additional information on design of movable high tunnels.



We provide Complete High Quality Kits for building both Cold Frames, Hightunnels and Commercial Greenhouses. These Kits are complete and include the Precision Bent Frames, State-of-the-Art Hardware and a selection Greenhouse Coverings. They are easy to construct and offer an affordable Solution to Extending your Crop Production.

See our Current Projects HERE!

Yuba County Starstruckture 30ft X 60ft

1. STARSTRUCKTURE GOTHIC ARCH Greenhouses - This system is 30 ft wide, by any length, Most popular is the 20 ft x 48 ft- 96 ft. These systems are made for Educational use, Farm and serious Gardeners and Commercial. They are made of 1 7/8" to 2 3/8" 30 ft greenhousegal. American made, Triple Galvanized Structual Steel Tubing. This system is a professional unit that provides max- mum growing area for both in-ground and bench systems. These systems come complete with all parts and many options. The V-Truss System insure strength take snow & wind loads easily. The Machine Hand Crank Roll-Up Sides ensure natural ventilation and you have the option of passive solar or hybrid electrical vents and fans. Other options include a tractor sized door, metal end walls sheeted with Twin-Wall® Polycarbronsonate panels. You can build this as a Vertical Sidewall Ground-to-Ground or Pony Wall Sidewall system.

30 ft wide STARSTRUCKTURE ensures maximum space for plants whether you grow on benches o in the ground and that means your garden will grow large and healthy. As are all of our kits- this unit is complete, from the Ground Posts to the Cover Film, including all hardware and even the drill bits and nut drivers. All you need to put this together is someone to help you stand it up, basic carpentry skills, drill motor, screw gun, ladders and a basic mechanical tool kit. Complete Instructions and guidance are supplied with the kit and Technical help is just a phone call away.

30 footers- . for full production and in the snow

2. The PRODUCER Hightunnel Greenhouses - These systems are similar to a hoop house but they are made from thicker 1.66 "diameter galhightunnelvanized steel tube. They are 20 ft wide by up to 154 ft long. These are 12 foot tall (or taller) at center. Most popular is the 20 ft x 48 ft model. These units have 'Straight Sides' offering more floor space & growing area as well as a Roll-up Natural Ventilation System on the two side walls- These units are built in place and are usually not movehightunneld from

Our 20 x 72 in production

location to location. Many growers use both in-ground, raised beds and/or benches in these units. These Hightunnel Kits are Complete-from the Newest woven poly Solaroof® cover option- to the one-piece frames - to the complete Hardware Package- even the drill bits and nut drivers are included. This system canbe put together by one person with minimal help- Just the basic carpentry tools and common sense- and, of course, as much technical help as you request from us...Although these are naturally heated and cooled utilizing passive roll-up sides (pictured at right), you can add whatever else you wish- including tractor door; optional heating; cooling; benches; shading; High Wind Kits and/or light deprivation systems.

Nevada City 20 x 48 footer under construction

3. Simple Hoop House Frames or Low Tunnel Greenhouses - These frames are utilized to build 8 ft to 12 ft wide structures that are 9 ft to 12 ft tall at center (depending on height of the straight sidewalls).

Simple 12 footer Hoop-style

They are made from 1.66 to 1.315" dia. galvanized steel. These are simple Cold Frames that are basically a simple series of hoops with hardware to connect the purlins and hold down the Agribon, shade cloth or greenhouse film. They can be easily set-up, taken down & moved again to any location. They can also be used to cover Rasied Beds- Although these frames can be used to build a basic tunnel-type Hoop House- the nest step up is to a Hightunnel design that is far superior for growing with maximum productivity.

Sloughhouse Mushroom Farm 20 footers under construction

Ananda Farm 12 footer under construction


A. TUFFLITE® 6 mil, UV, AC Poly is the trade standard and the default covering for our kits- This material works well and should last at least three years. This product costs $ .18 (cents) per square foot.

B. SOLAROO Greenhouse Coverings- is a new woven poly greenhouse covering material that we prefer to regular poly. This material, developed in Israel, is a state-of-the-art material that traps heat in winter, utilizing Infrared, Ultraviolet blocking agents and also an Anti-condensate. This material diffuses light so it is much better for the plants within it. Since it blocks infrared light, insects inside of the greenhouse / hightunnel are blind! It is guaranteed for at least 5 years and has held-up longer than that in our uses. This option costs $ .32 (cents) square ft or current market price.

Left- Greenhouse Installers walking on top of a SOLAROOF greenhouse cover.







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Starstruckture Gothic Arch Greenhouses STARSTRUCKTURE


30x48 High Altitude SNOW PRO


30 ft x 72 ft Starstruckture30 ft x 100 ft Starstruckture



20 ft x 48 ft Producer20 ft x 72 ft ProducerSuper Producer

20 ft x 96 ft



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