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Overview

The Gigant greenhouse delivers exceptional scale and performance. Crafted in Belgium by Janssens, with a sturdy tubular aluminum frame and 4 mm tempered glass, it features a tall roofline and a vast interior, providing generous space for taller plants and projects. The design allows flexible placement of doors and windows, making it adaptable to both your space and your gardening style.

For dedicated gardeners and hobbyists, the Gigant greenhouse offers a bright, durable environment where plants thrive, and creativity flourishes. It combines European design heritage with modern engineering for lasting beauty, reliability, and year-round inspiration.

Please note: Because the Gigant can only be purchased as a customized model, a special order must be placed with the Janssens factory in Belgium. Lead times are longer than other models.

Key Features

Belgium Engineering

Designed and manufactured in Belgium

Tempered Glass or Polycarbonate

28” wide- 4mm tempered glass or 10mm twin-wall polycarbonate

17-Gauge Aluminum Frame

Provides sturdy structural support

Reinforced Frame

Extra support in the roof, sidewall, gable ends

Roof Vents

Support natural ventilation

Sliding or Hinged Doors

Smooth access and airflow

Gutters

Helps manage rain runoff

Specifications

Glazing: 4mm tempered glass panes OR
10mm twin wall polycarbonate
Frame: 17 gauge tubular aluminum extrusions
Heavy duty portal frame supports
Heavy duty gable end supports

Colors: Black (RAL9005), Fir Green (RAL6009), White (RAL9010)
Custom colors also available - see below

Dimensions

Since Gigant greenhouses are offered only as a special order, they have no default length or width - these dimensions may be customized within certain parameters.

The charts below show possible dimensions for the Gigant greenhouse. Note that the width of the greenhouse will determine both peak height and roof pitch.

gigant greenhouse dimensions

*Dimensions are approximate conversions from metric measurements and should not be relied on for assembly purposes. Contact Exaco for more information.

Extra Height

One major advantage of the Gigant greenhouseis the option to extend it's walland peak height by adding a second level of glazing panels to the side walls. The options for extensions are:

  • 1'0"
  • 1'8"
  • 2'11"

Additional Options

Doors & Windows: There is no standard configuration of doors and windows. Customers may select their desired options from the 'Accessories' list to the right. Please note that double doors can only be installed in walls that contain at least 4 panels.

Glazing: Customers may substitute narrow panels (~1'2" width) for the standard glazing panels (~2'4" width) at a rationof 2:1.This will not affect the overall dimensions of the greenhouse.
On the roof of glass models, customers may substitute polycarbonate glazing panels for the glass glazing panels.

Decorative Panels: Customers may choose to add decorative metal panels along the bottom of the side walls, identical to those found on the Retro Victorian greenhouse.

Colors: Customers may choose a color from the RAL Color System outside of the default options.

Special Notes

The Gigant greenhouse is an advanced build and should only be assembled by a contractor or highly skilled handyman. Please consider the following:

  • On glass models, the roof glazing panels are extremely large and heavy and may require additional support scaffolding during assembly.
  • Hardware for attaching this greenhouse to a building is not included
  • Weather stripping for sealing the gap between this greenhouse and a building is not included.
  • Due to the high level of customization for this greenhouse, Exaco cannot provide structural certifications (but we can put you in touch with the engineering firm that provided ours).

Frequently Asked Questions

Do I need a professional assembler for my Janssens’ glass greenhouse? If so, how do I find one?

Many of the Janssens’ greenhouses are designed to be a DIY assembly by handy homeowners, however, this model may have some challenging sections that it may be better to have a professional assembler do. Hinged doors, knee walls, cupolas, heavy framing, T-shaped models and larger sizes are all things that can add to to level of assembly – depending on the model and options you choose. We do maintain a referral list of independent assemblers, please give us a call or email us and let us know where you are located and your greenhouse and we put you in touch with a couple assemblers in your area. If you prefer to work with someone local -handyman businesses and landscapers are great assemblers too! Exaco does provide all US customer support and we are here to help with any assembly questions that you or your assembler may have. Just give us a call!

What if I need assembly help?

Exaco is here to help! Our friendly customer support staff is REAL PEOPLE who have assembled these greenhouses and are very familiar with the parts and pieces. Please give us a call or email us. We are also able to video calls via Facetime or Google Meet as needed. We want to help you to get through any assembly questions so you can get to the fun part – enjoying your new greenhouse!

Where are Janssens’ greenhouse made?

Janssens has been manufacturing quality greenhouses for over 75 years in Lier, Belgium.

Can someone help me decide which greenhouse is best for me?

Our retailers are great resources to reach out to discuss greenhouses – and our Exaco customer service team is always ready to help your dream greenhouse come to life – we are just a call away. Over the years we have personally supported many customers choose their greenhouse and options – and that expericence goes a long way. You can also find additional resources and inspiration on our blog too.

Do I need a permit?

You might need a permit. Not everyone does and even sometimes those who do need a permit do not apply for one. Each municipality sets their guidelines for what types/size of buildings need a permit in their area – sometimes this is based on square footage or whether they consider it a “permanant structure” – but this is all decided by your local permit office. If you are applying for a permit, you should always go through this process BEFORE you order your greenhouse – depending on local wind/snow load requirements you may need additional reinforcements or supports to reach your local requirements. You may also find other restrictions for placement that may mean you have to limit the size or location. If you are going to get a permit, it is always best to know the restrictions ahead of time.

Do you provide structural certifications for special order Janssens greenhouses?

Exaco does not provide structural certification for special order/custom greenhouses. Janssens’ greenhouses are strong – but if you need a structural certification or are applying for a permit you should do this before ordering the greenhouse. Depending on your location and local code requirements you may need to add additional supports/reinforcements to your kit and this will be best ordered with the greenhouse. Within the special order category they range widely in size, anchoring, upgrades and supports added so there is not a “one size fits all” certification that can apply. Exaco can provide the certifications for a fee or direct you toward an engineer that can assist you with the documentation you need. Keep in mind, each location/state has different load requirements. If you are in a location that has higher load regulations, you may need to purchase additional reinforcements.

Resources & Documentation

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