Where Luxury Meets Limitless Possibility: The Janssens Gigant Greenhouse
For those who dream beyond the garden, the Janssens Gigant Greenhouse redefines what a greenhouse can be. Whether you’re building a serene plant haven, covering a pool, setting up a sauna retreat, or creating the ultimate entertaining space, the Gigant offers bold space, elegant design, and total customization. It’s a show-stopping structure that transforms your backyard into something extraordinary.
With soaring ceilings up to 13 feet and a flexible layout, this premium glasshouse from Belgium is a true architectural statement—designed to elevate your lifestyle as much as your gardening.
Unmatched size, strength & style
Crafted with oversized black aluminum profiles, the Gigant boasts more strength and rigidity than standard greenhouse kits—making it ideal for year-round use, even in demanding climates. Paired with 4mm tempered glass or optional 10mm twin-wall polycarbonate on the roof, it offers a stunning balance of light clarity and insulation.
From the framing to the glazing, every element is engineered for long-term strength, thermal performance, and timeless elegance.
Custom-crafted to your vision
The Gigant isn’t a one-size-fits-all greenhouse—it’s a fully custom-ordered structure tailored to your needs.
You choose the size, door style, ventilation, and extras. Want sliding double doors on the side and hinged entry in the back? Done. Need more ventilation for a tropical orchid collection—or fewer windows to keep your sauna warm? No problem.
Popular starter configurations are available to help you envision what’s possible, but everything is designed and built to order.
Built for more than plants
This isn’t just a greenhouse—it’s an extension of your home. Customers have turned their Gigant into:
A cozy retreat for cocktails and conversation, right in your backyard.
A glass-enclosed dining room for unforgettable meals with a view.
An elegant way to swim in comfort, rain or shine.
A striking venue for day-to-day celebrations, special occasions, or workshops.
Spa-like relaxation with full protection from the elements.
With the Gigant, your imagination is the only limit. Whether you’re growing tropicals, entertaining guests, or enjoying a quiet afternoon surrounded by greenery, it provides a climate-controlled sanctuary that adapts to your lifestyle.
Premium construction with a heritage of excellence
Built by Janssens, a leading European greenhouse manufacturer with over 75 years of experience, the Gigant delivers on every promise: beauty, performance, and long-lasting durability. Each greenhouse is imported by Exaco, known for top-tier customer support and expert service.
Ready to create your ultimate outdoor escape?
Bring your vision to life with the Janssens Gigant Greenhouse—where bold design meets endless customization. Whether you’re growing rare plants or crafting an unforgettable living space, this is the greenhouse that rises to the occasion.
Custom Gigant for Inspiration
More Gigant Inspiration
Product Details
Large glass greenhouse with great insulation for ample space to host gatherings and/or grow plants
More strength: Larger, thicker, stronger aluminum profiles than those of any competitor in this price range
Taller design for more headroom: 12′ peak is higher than any other greenhouses
Frame material: Thick, strong aluminum frame
Frame finish is applied electrostatically for a thicker application and better coverage
Sidewall material/thickness: 4mm tempered glass
Roof material/thickness: 4mm tempered glass OR 10mm twin-wall heat-block polycarbonate
Great insulation: Tightly fitted design with rubber seals between frame and glazing, as well as sealant around windows
Door: you can choose between sliding or hinged doors as a single or double door; can be installed on any vertical glass location at the front, back or sides. Choose your favorite door type or use in combination!
Roof vents: Add any number of roof vents (29″ x 33″) for effective ventilation; with automatic non-electric openers that open the window when it gets too hot in the greenhouse
Window: Add louver vents or top-hanging (push-out) windows to your liking
Portal frame (support bars): Additional support for the size of the greenhouse. You can customize for high wind or snow conditions.
Rainwater gutter system: Gutter with downspouts on both sides
Warranty: 15 years limited
Made in Belgium
Imported by Exaco Trading: We are a proud dealer for Exaco because they offer high-quality products with excellent customer service to help you with any post-purchase problems (if they occur).
Specifications
Stem wall: available for 8″, 16″, and 24″
Expandable: No
Frame color: Black
Glass panel widths: 14″ or 29″
Sidewall height: 6’8″ – 9’7″
Peak height: 9’10”-12’9″
Available widths: 15′, 17’5″, 19’10”
Available lengths: various from 15′ to 58’7″
Floor space: 215 – 1162 sq. ft.
Included In Standard 15×20:
Sidewall height: 6’8″
2x Portal Frames
1x Double Hinged Door
6x Auto Roof Windows
4x Louvre Windows
Included In Standard 15×25:
Sidewall height: 6’8″
3x Portal Frames
1x Double Hinged Door
6x Auto Roof Windows
4x Louvre Windows
Included In Standard 20×20:
Sidewall height: 6’8″
2x Portal Frames
1x Double Hinged Door
6x Auto Roof Windows
4x Louvre Windows
Included In Standard 20×30:
Sidewall height: 6’8″
3x Portal Frames
1x Double Hinged Door
8x Auto Roof Windows
6x Louvre Windows
Included In Standard 20×40:
Sidewall height: 6’8″
4x Portal Frames
1x Double Hinged Door
10x Auto Roof Windows
8x Louvre Windows
Included In Standard 20×60:
Sidewall height: 6’8″
7x Portal Frames
2x Double Hinged Door
14x Auto Roof Windows
10x Louvre Windows
Shipping & Assembly
Assembly time: Plan at least a full weekend and get some helpers. It is highly recommended to hire a contractor to assemble this greenhouse because of the large dimensions. You may also need to plan more time to prepare the base because you will need to build a concrete footer.
Shipping Information
This product is delivered via LTL which is curbside delivery only. The driver will be using a pallet jack and liftgate to slide the crate off and will need help from the customer with the unloading of the framing boxes. We recommend having a couple of people there for the delivery.
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