Using screws should be aware that the center axis of the aperture should be located no closer than 36 mm from the edge of a plate, and the aperture itself should have a diameter for 2.5-3 mm larger than the diameter of the screw - to compensate of thermal expansion. The recommended distance between the self-tapping screws - 400-500 mm for sheets of 8-10 mm and 600-800 mm for sheets of 16 mm. During the installing of a very long (more than 7 m) of whole sheets of aperture the screws should be oval, with long axis oriented along the plate. The aperture must be drilled for tapping only in the middle of the inner air channel list MUST NOT attempt to drill apertures through the center bar of the sheet.
Using sealing washers it is not necessary to apply excessive efforts tightening the screws. The effort necessary tightening the screws, should be chosen that the loading transferred by a sealing washer to polycarbonate sheet, there were in limits of 0,5-2 kg/sm2. Traces of deformation of sheet under a washer (deflection) shouldn't be observed visually.
Seals
If necessary additional compacting of joints it is recommended to apply sealing tapes from following materials - silicone rubber, a neoprene, ЕРDМ. It is not recommended to apply sealants from soft PVC as some sorts of elastic polyvinyl chlorides at aging and under the effect of atmospheric influences are capable to allocate the substances destroying the polycarbonate.
During compacting of joints polybutylene mastic (or a tape), and also the silicone hermetics compatible to polycarbonate can be applied as hermetics. Silicone hermetics on a basis of amines or benzamide are incompatible with polycarbonate and can cause its destruction. Application of one- or two-componental polysulphidic hermetics is admitted.