Change of length (width) of sheet is considered under the formula:
∆L = L x ∆T X,
Where L - length (width) of sheets (m)
∆T - temperature change (°C)
X = 0,065 mm / ° Sm - linear temperature expansion of cellular polycarbonate rate.
For example, at seasonal change of temperatures from-40°C to +40°C each sheet meter will undergo change on ∆L = 1x80x0,065 = 5,2mm. Thus it is necessary to note that color sheets heat up on 10-15°C more than transparent and white. ∆L for "bronze" panels can reach 6 mm on each meter of their length and width. In areas with less severe environmental conditions change of the linear sizes of panels, of course, will be essential low.
It is necessary to leave thermal backlashes at connection and fastening of sheets among themselves in the flatness, and also in angular and ridge connections, using special connecting, angular and ridge profiles for installation. Point fastening of sheets to a design carcase it is desirable to use screws with special thermo washers, and it is necessary to do apertures slightly more in panels.
It is impossible to mount constructions without thermal deformation of sheets in the street. It can lead to their distorting in summer and to damage up to rupture in winter.