Ovaltech
Freestanding Greenhouse with curved walls
The Ovaltech greenhouse, with its curved walls and gothic shape, offers excellent resistance to wind and snow. Its flexible design allows for a wide range of widths and customizable lengths, with the possibility to integrate various equipment according to production needs. Its large air volume creates a more stable internal climate, promoting plant uniformity and higher productivity per square foot. A smart investment, focused on quality and built for the future.
Suitable for
- Soft fruits
- Vegetables & Herbs
- Flowers
- Ornamental Plants
- Tree & Shrub Seedlings
- Leafy Greens
- Specialty Crops
Made in Canada, shipped worldwide.
Local installation across Canada, USA, and Mexico.






Benefits
- Superior air volume creates a more stable climate at plant level
- Gothic profile provides superior light transmission
- Installation possible anywhere on your property
- Quick ROI
- Easy to modify or relocate
- Each greenhouse can have its own climate settings
- Cold or heated greenhouse
- Option: Double-inflated polyethylene
- Quick installation
- High wind & snow load resistance
- Wide adaptability for diverse crop production
- Advanced adaptability for various technology levels
- Engineered to comply with International Building Codes (IBC)
NRCS High Tunnel Initiatives – Harnois is an approved manufacturer
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 Greenhouses
Ovaltech I, III & IV
- Widths: 20‘ to 42‘ (6m to 12,8m)
- Lengths: Depending on your requirements
- Top Clearance: 9‘-2 to 21‘ -3‘‘ (2,8m to 6,5m)
Structural steel
All our structures are made with Galvalume steel, ensuring superior corrosion resistance and long-term durability.
Galvanized oval tube
Our tubes are oval-shaped, preventing the polyethylene from coming into contact with sharp edges, which helps extend its lifespan.

Available on: Ovaltech I

Available on: Ovaltech III

Available on: Ovaltech IV
Ovaltech I
- Widths: 25‘ et 27‘
- Arch Spacing: 5‘
- Top clearance: 11‘-2‘‘ et 11‘-5‘‘
Ovaltech III
- Widths: 25‘, 30‘, 32‘, 35‘
- Arch Spacing: 3‘, 5‘, 6‘, 8‘
- Top clearance: 14‘-1‘‘ à 15‘-9‘‘
Ovaltech IV
- Widths: 25‘, 30‘, 32‘, 35‘, 42‘
- Arch Spacing: 3‘, 4‘, 5‘, 6‘
- Top clearance: 14‘-1‘‘ à 17‘-2‘‘
Options
- 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)
- Available equipment:
- Climate controls, including thermal screens and heating systems
- Insect screens
- Lighting and ventilation systems
- Door options:
- Growing tables
- Single or double
- Sliding or swinging
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.
Contact your local agent
Start your operation or expand with ease using a freestanding greenhouse—contact us or request a quote today!