Freestanding Greenhouse Structure

Made in Canada, shipped worldwide.

Local installation across Canada, USA, and Mexico.

Ovaltech - Freestanding Greenhouse

The Freestanding Commercial Greenhouse is an outstanding choice for growers seeking an independent, versatile growing structure designed for durability and optimal crop production. These ground-to-ground greenhouses provide a reliable production space that can adapt to various needs.

Each freestanding greenhouse operates as a self-contained unit, allowing growers to manage specific crops or environmental conditions without impacting other structures. With customizable widths and lengths, these greenhouses maximize usable growing space while enhancing crop development and operational efficiency.

Our freestanding greenhouse offers a cost-effective alternative to a gutter-connected structure of the same size, requiring less investment while providing extreme versatility in function and purpose. Its superior air volume enhances climate stability at plant level through the buffer effect, reducing temperature fluctuations and improving overall crop health. Designed for adaptability, this greenhouse supports various growing applications, from vegetables to ornamental plants, while optimizing energy efficiency and environmental control. Whether for commercial production or research, it delivers reliability, performance, and long-term value.

Built from certified structural steel with a minimum strength of 50 ksi, freestanding greenhouses are 52% stronger than standard commercial steel tubing. Their oval or gothic designs minimize wear on polyethylene films, ensuring a durable, long-lasting environment that supports consistent production.

Freestanding greenhouses are designed with great height and ventilation options, including ridge vents, side roll-up vents (manual or automated), and mechanical systems like fans and air circulators. These features promote superior natural ventilation and effectively manage water, ice, and snow buildup, providing an optimal growing environment year-round.

Suitable for

Freestanding Greenhouses Produce
Freestanding Greenhouses Flowers

Product Benefits

Key Features

Freestanding Greenhouses

Ovaltech I, III, IV & IV

  • Available width: 20′ to 42′ (6m to 12,8m)
  • Top Clearance: 9′-2‘’ to 21′-3‘’ (2,8m to 6,5m)
  • Foundations Options: 
    • X rods with anchor tubes
    • Anchor plates
    • Sonotube
  • Covering Options:
    • Single or Double polyethylene films (7.2 mil)
    • Single or twin wall polycarbonate sheets (8mm)
    • Shade Cloth
  • Ventilation options
    • Single or double ridge vent panels
    • Mid-roof vent
    • Side roll-up vent (manual or automated)
    • Mechanical ventilation (fan, extractor and air circulator)
  • Door options
    • Single or double
    • Sliding or hinged
  • Available Equipment:
    • Tables
    • Irrigation
    • Climate controls
    • Heating
    • Insect screens
    • Lighting

Steel Oval Tubing

All our structures are made with Galvalume steel, ensuring superior corrosion resistance and long-term durability.

Learn more

Harnois_Oval_Arch_A
16 Gauge
Available on: Ovaltech I
Harnois_Oval_Arch_B
16 Gauge
Available on: Ovaltech III
Harnois_Oval_Arch_C
14 Gauge
Available on: Ovaltech IV

NRCS High Tunnel Initiatives – Grants for Freestanding Greenhouses 

While the NRCS offers both technical and financial assistance to farmers, partnering with an approved manufacturer like Harnois ensures a smoother transition from your initial vision to the final implementation. Our expertise aligns seamlessly with the rigorous application process of the NRCS, which prioritizes a clear conservation plan, a thorough assessment of resources, practice design, and continuous monitoring. Together, we strive to promote sustainable farming and make high tunnel integration a beneficial experience for all.

Freestanding Greenhouse Projects

Sectors of activity
EN – Filtre de projets
Animals shelter

Ferme Miclerc

Floriculture

Good Year Farms

Garden Center

Jardin du coin 

Floriculture

La Maison des fleurs vivaces

Soft Fruits

Les Fraises de l’île d’Orléans inc. 

Herbs

Les Serres Gourma

Contact your local agent

Start your operation or expand with ease using a freestanding greenhouse—contact us or request a quote today!