Abstract: Greenhouse construction consisting of a number of rooves with supporting members, such as longitudinal beams, ridges and gutters. These supporting members are provided with rails for moving a carriage or the like over them. The rails and supporting members provide each other with structural strength so that a relatively slim construction with no or hardly any restriction in the light level in the greenhouse construction occurs.

Abstract: Partition for separating the interior of a building construction such as a greenhouse from the surroundings. This partition is fitted at an inclination and is of multi-walled, such as double-walled, construction. According to the invention, the separation wall facing the interior of the building construction is provided with a layer of water with such a small thickness that a free space remains between the wall of the partition facing the outside and the layer of water. It has been found that the temperature in the interior of the building construction can be accurately controlled in this way. By means of the choice of the liquid used to build up the layer, it is possible either not to influence the transmission of light or to modify the transmission of light.