TechSoft beam-mounted ventilation systems

Aid to selecting drives for beam-mounted ventilation systems

Here you can find out which are the most appropriate Lock products for your project. Simply key in three parameters (flap width, flap dimension and number of flaps per rack) to obtain a proposal for the optimum LZG (rack & pinion gear unit) to suit your load scenario. When you then go on to indicate the total number of flaps for 1 EWA (power drive), the system identifies the EWA you need to have to get the job done.

This selection aid can be used for projects that have the following parameters:

  • Flap widths [BK] of 3.20 m, 4.00 m, 4.27 m and 4.80 m
  • Roof angles [α] of between 22 ° and 25 °
  • A glass thickness of 4 mm (10 kg/m²)
  • Height [TR] of push-pull tube, measured from upper edge of gutter bracket, of between 11.5 mm and 60 mm
  • Height [Hzd] of push-pull tube, measured from upper edge of gutter bracket, of between 11.5 mm and 60 mm
  • No insect protection net! For applications with insect protection, the details for the ventilation flaps reduce as a consequence of their extra weight.
  • With a net weight of 1800 g per linear metre, the value for flaps must be reduced as follows:
    • For a flap width of 3.20 m: – 25 %
    • For all other flap widths: – 20 %

The selection fields contain a sub-set of the roof systems available on the market. If you are unable on our tables to find the ventilation flaps or system dimensions you are planning to use in your project, we will be pleased to help you work out which types of LZG and EWA you require for ­ an optimum drive system configuration.


The torque required for the LZG is based on the linear load rating of the rack. Loadings applied by push bars are not taken into account here, and must be dissipated by the rail mounting on the building structure. The figures in these tables are non-binding.


The table calculations are based on the German greenhouse standard DIN EN 13031-1 : 2003-09 greenhouse dimensions and construction - part 1: Culture greenhouses. This was based on the German edition EN 13031 – 1 : 2001.

Lock Beam-mounted ventilation system for applications