All Janssens’ greenhouses are produced by our own employees at our headquarters in Lier. With more than 75 years of experience, we are among the top European greenhouse builders. Our greenhouses are exported worldwide. Find your nearest sales point for more information.

Our dealers often display only our action models: greenhouses in fixed setups. However, we also offer custom models, greenhouses that you design yourself with various options and accessories. In need of a greenhouse with different dimensions or alternative equipment? Ask your local dealer!

Aluminum is a light, ultra-strong and durable material. It does not rust and requires minimal maintenance. Because aluminum is so sturdy even in slim tubes, we can make the glass rods exceptionally narrow, allowing extra light into the conservatory. In addition, the material is 100% recyclable and therefore circular.

The size of your greenhouse naturally determines the amount of crops you can grow in it. A large greenhouse offers not only more space, but also a more stable environment for your plants. The temperature there is more constant, and you will notice this in your growing results.

In addition, you have more space to move around and comfort, and you can do crop rotation more easily.

Aluminum does not rust, but it does corrode. That is, reddish-brown deposits do not form on the aluminum, but white ones do. This mild corrosion is a natural process and does not affect the strength or durability of the tube profiles.

Thus, the surface treatment is purely for the appearance of the greenhouse. The paintwork we offer at Janssens is always a high-quality powder coating. This paintwork is an electrostatic process, where the powder is plated on in an oven.

In our custom models, you choose the location, quantity and type of doors and windows. The options depend on your chosen model and size.

Our action models are standard construction kits. You can add options, but installing additional roof or side windows is not possible.

Janssens’ greenhouses are equipped as standard with safety glass 4 mm thick. We offer the option of choosing polycarbonate.

Cheaper brands usually use traditional horticultural glass of 3 or 4 mm thick. That type of glass is more economical, but also much less strong. And when it breaks, it disintegrates into dangerous shards.

The safety glass used by Janssens is up to seven times stronger. In the exceptional event that it breaks, it disintegrates into small, harmless pieces.

Do you want to completely rule out glass breakage and also provide extra insulation? Then polycarbonate is a good choice. These plastic panes consist of clear double sheets. The material is very strong and can withstand the impact of hailstones or a soccer ball, for example.

The double layer of polycarbonate insulates better than glass, keeping the temperature more stable. So it is ideal if you want to heat the greenhouse in winter.

The downside of polycarbonate? It is sometimes seen as “cheap” because the material is not transparent. On the other hand, it does filter incoming sun rays.

Give your greenhouse a cleaning twice a year. Be sure not to use harsh cleaning agents.

Moving parts, such as wheels and hinges, can use some oil from time to time.

Close skylights during storms to prevent them from ripping loose.

Do you have automatic window openers? The cylinder can freeze to pieces in freezing temperatures, so be sure to take it out when the temperature drops below zero.

During very heavy snowfall (rare in our areas), clear the roof of snow. 

Greenhouses are increasingly being used as a second living room. Want to set up your greenhouse as a relaxation area? Then take into account the climate inside: high temperature fluctuations, lots of sunlight which can cause discoloration, high humidity in between seasons, drafts, condensation and water infiltration under and in the roof. All characteristics specific to a greenhouse.

These rules are very specific and vary by country and region. Because of different local regulations, we recommend that you check with your local government.

relaxationThe greenhouse must be placed on a sufficiently load-bearing (concrete) foundation that is provided to solid frost-free ground. The dimensions listed of our aluminum structures are always the external dimensions of the structure. We recommend a concrete foundation as a ring beam on the outer dimensions of the greenhouse. This should be 100% level and flat so that the bottom profile can be mounted on it. The type of foundation (width, depth, composition) depends on the building situation, subsoil, region and contractor’s practices. We recommend getting detailed advice on this from your professional. (my note to Peter, who do you mean by your professional? It is not clear even to me.)

Our greenhouses come standard with an aluminum foundation beam with a ground anchor at each corner. In consultation with your expert it is possible in certain cases (smaller greenhouses) to anchor only the 4 corners of the greenhouse, in which case the option of a lowered door threshold is NOT possible!

Before you start installing the greenhouse, you should think carefully about: the location of the greenhouse, its orientation and the position of the door and windows. 

Do you want to build your greenhouse on a Dwarf wall? Make sure the wall is straight and all corners of the wall are 90 degrees. The wall needs to be thick enough, be made of solid and not cavity bricks or blocks, be flat and smooth on the top, be built to the correct dimensions etc.

Are you having the greenhouse installed by a professional? Make sure the ground is clear and level before the team arrives. 

Tip: Enquire in advance about the foundation required.

What you see is called ‘oxidation’ of the aluminum 

Aluminum, when exposed to water and oxygen will very quickly corrode. Most can identify rusted steel from its familiar orange color. Aluminum corrosion actually looks white. The process of aluminum corrosion is known as oxidation. The resulting aluminum oxide is a thin, hard layer that actually protects the metal from further corrosion, it does NOT harm the profile or its statical characteristics!

You can try intensive cleaning but there is a chance that what you see is a phenomen called ‘glass corrosion’ and cannot be removed.

If glass is stored in such a way that moisture (rain, condensation, humidity) comes between the densely packed panes, the glass surface area gets into contact with a tiny amount of humidity. Note: even when covered, humidity can enter the plastic packing depending on weather conditions or rise from below (ground, soil, grass, …). That means that the humidity that enters between the glasses will have a very high concentration of sodium, and a strong alkali solution (Na+ OH-) is formed. At high pH-values, the glass network is attacked and sodium silicate is formed. This can be reinforced with heath (when sun is shining and heating the box of glass, wrapped with plastic foil.  If this process is allowed to continue in the packaging, the glass will be destroyed, and the panes will be glued together by the sodium silicate (water glass).

This is not covered by guarantee; therefore, we strongly suggest storing packages and glasses at a dry place, protected from the sun until the day of mounting your greenhouse!

The greenhouse should be mounted completely level across the width, but we recommend you let the greenhouse slope slightly on the long side (max. 2-3mm per meter), this way you stimulate the drainage of rain and melt water.

If you don’t start assembling immediately, store the packages and the glass pallet dry. If glass is stored in such a way that moisture (rain, condensation, humidity) comes between the densely packed panes, the glass surface area gets into contact with a tiny amount of humidity. Note: even when covered, humidity can enter the plastic packing depending on weather conditions or rise from below (ground, soil, grass, …). 

Example: a glass pallet left in the sun for several days on damp ground (wet grass) is not a good idea! The moisture that evaporates under the plastic packaging in this way cannot dry out and also creeps in between the glass panels.

When it comes to quality and durability, our 4 mm thick safety glass is the best choice. Do you want better insulation or more protection from the sun? Then you can opt for twin wall sheets of 10 mm in polycarbonate.

To evacuate condensation in the channels or cells of the polycarbonate roof sheet and regulate air circulation inside the sheet, we provide them with AntiDust tape as standard: closed at the top, perforated at the bottom.

To avoid overheating, it is best to choose a southern orientation, that is, with the greenhouse’s entrance facing south. That way your greenhouse gets maximum sun in both morning and evening. And you minimize the chance of overheating.

Do you want to grow heat-loving plants such as cacti or succulents? Then it’s best to keep a western orientation to give them maximum sun in the afternoon. Even in winter, the greenhouse will then be a little warmer around noon.

The average hobby greenhouse is mainly intended to grow plant species that do not thrive in our climate in the open: peppers, tomatoes, eggplants, peppers, melons …

Want to use the garden greenhouse to overwinter plants such as fuchsias and orangery plants? Then you will probably need to heat the greenhouse with a gas or electric system.

Heating a greenhouse is not cheap. Insulate the greenhouse by installing bubble wrap, for example. Or choose a greenhouse with twin wall polycarbonate, which insulates better than single glass. Install a thermostat (low to the ground) to keep the temperature in the greenhouse constant and to use less energy.

Ventilating your greenhouse is very important. Especially in the summer months, the temperature can get high. Many of our models are equipped with skylights and side windows. An automatic window opener is a budget-friendly option that gets the air flowing by itself on hot days. 

Only for deliveries from Janssens in Belgium and the Netherlands!

After purchase and payment, you will receive an email with an order confirmation. A staff member will contact you within a few working days to arrange the delivery date. You will then receive an email confirming the appointment.

The unloading location must always be accessible by truck. If this is not the case, an alternative unloading location must be provided. In case of obstructions, car-free zones, too small alleys, … costs can be charged.

The delivery is always unloaded next to the truck. The driver is not in a position to move the greenhouse any further, to carry it into the garden or to take back packaging material. If the driver has a crane, it can be dropped off at range (10m). The driver is NOT permitted to drive on unpaved roads/pasture/ driveway (also at the customer’s risk).

Janssens does not perform assemblies, for this you need to coordinate yourself with your distributor or mechanic.

A typical delivery consists of:

• Standing pallet with glass, 90 x 90 x 220 cm, 500 kg
• Apackage equal to the width of the greenhouse x 25 x 15 cm
• A package the size of the length of the greenhouse x 25 x 15 cm

You enjoy the following warranty periods:

• 10 years on quality and alloy of aluminum
• 10 years on paintwork (powder coating) in case of detachment, peeling, flaking, corrosion, chalking, discoloration and loss of gloss in which the predetermined tolerances are exceeded according to Qualicoat or Qualinod specifications
• 10 years on adhesion and tension of glazing rubbers
• 10 years on manufacturing defects in the glass
• 5 years on PVC components and their UV resistance

These damages are not covered by the warranty:

• damage due to non-observance of installation and operating instructions
• damage as a result of use other than normal use
• damage as a result of lack of maintenance
• normal wear and tear
• materials and items used at the customer’s request
• constructions that are not part of the Janssens product range but were manufactured at the express request of the customer or distributor.

Our greenhouses are intended for the cultivation of vegetables, fruit, flowers, etc. The following properties are inherent and vary according to the situation, environment and use:

• condensation on glass or profiles
• drafts on doors, windows or gaps
• skylights, roof connections and gutters are not 100% watertight
• no water barrier under the foundation profile

If you don’t start assembling immediately, make sure that the packages and the glass pallet can be stored dry. Avoid at all times that moisture can get into the packaging or between the glass: after heating by the sun or evaporation this can fog up the glass or the profiles, causing a “haze” on the glass or the paintwork of the profiles that can no longer be removed. Example: a glass pallet left in the sun for several days on damp ground (wet grass) is not a good idea! The moisture that evaporates under the plastic packaging in this way cannot dry out and also creeps in between the glass panels.