The aluminium super-structure gives the Dutch Venlo Greenhouse it’s characteristic apparel. The choice for aluminum over steel is due to the material’s weight, strength and the possibility to create detailed profiles with it. The core function of the aluminium roof system is to hold glass in its place and to discharge fallen rainwater as gutter. In many cases a rubber gasket is applied to ensure a water and wind tight seal between the glass and aluminium.
The aluminum roof- and gutter systems are calculated and engineered with great care. Just like the Steel Structure, the aluminium system is carried out as light and as strong as possible. Constructive engineering is done with the Dutch “The City of Glass” which enables the greenhouse to withstand the external forces according to industry regulations.
In the Venlo greenhouse, glass panes are directly mounted into the profile of the aluminium gutter. Because of the tight seal, the glass itself can also function as gutter in the case of heavy rainfall. This characteristic makes the aluminium roof system highly efficient and desired by growers around the world.
As described earlier, the aluminium greenhouse gutter does not only collect the rain and snow, but it fulfills a crucial constructive role. This ingenuous system cares for the strength in the gutter-direction of the greenhouse. It significantly reduces the amount of material required to construct the greenhouse.
Next to this, the gutter also collects condensation water from the glass on the inside of the greenhouse. If required by regulation, this can be discharged separately from the rainwater. This condensation water function of the gutter prevents water dripping on the crops, which can cause damage in the form of burn spots or physical damage.
The profiles (glazing-bars) between the glass form the self-supporting roof system with the lowest light interception possible. These glazing-bars have patented designs to prevent glass breakage, leakage and to use least material.
For service buildings or other appliances, there are different profiles available, using the same gutter. This provides multiple options for the choice of covering material. The patented profiles are also available for sandwich panels, polycarbonate and even solar-panels, rather than only for 4 mm float glass.
The aluminium glazing-bars are not only used for the roof of the greenhouse, but also on the gable walls. The choice of material for these profiles can also differ between glass and polycarbonate and sandwich panels.