Polycarbonate is a thermoplastic material with excellent mechanical, thermal, and optical features. Polycarbonate roofing usually is delivered as polycarbonate sheets or polycarbonate panels.
Polycarbonate sheets, polycarbonate panels
Both polycarbonate sheets and polycarbonate panels are made of the same material but have different sizes. Both polycarbonate sheets and polycarbonate panels are lightweight roofing products as the material itself is hollow (contains a system of longitudinal cavities).
The polycarbonate properties can be further improved with:
- UV (ultraviolet radiation) filters, usually applied during coextrusion of the roofing panel or sheet;
- special additives reducing the extensive interior heating (greenhouse effect);
- various colors;
- various cavity structures. The cavities structure has a huge impact on the flexibility and load capacity of the polycarbonate roofing.
Mechanical features of polycarbonate roofing
The polycarbonate sheets or panels have very good impact stress resistance parameters (no problems with smaller stones falling on the roof), the impact resistance of polycarbonate is 200 times higher than the impact resistance of glass.
The great on polycarbonate roofing is the fact that the mechanical properties do not change very much with varying temperatures. The polycarbonate panels remain the same impact-resistant with -5 Celsius degrees as well as +40 Celsius degrees. Its thermal dilatability is 0,065 mm/(m·K) which, in Europe or Northern America means that the polycarbonate sheets can dilate by 3 millimeters per 1 meter of their length (summer/winter dimensions differences).
Optical properties of polycarbonate roofing
- The light permeability of the clear not colored polycarbonate panel is between 50% and 90% (pure glass has 90% – 95%).
- Any coloring decreases the ability of polycarbonate to transmit the light through.
- All polycarbonate roof panels transmit a large part of the visible and also infrared specter.
The UV stability of polycarbonate roofing
The majority of plastic materials degrades over time being exposed to ultraviolet radiation. To avoid such material degradation the polycarbonate roof panels are treated with UV filters (from the upper side only or from both sides).
If the UV filter was applied only from one side, this side is usually covered with protection foil and it is necessary to install the roofing panels with this side up.
Fireproofness of the polycarbonate roofing panels
- Compared to other plastic materials, polycarbonate offers rather high fire resistance.
- It is hardly combustible (burns 40 mm/min) and when burning it doesn´t drip.