Accelerated weathering tests in a weatherometer produce little change in light transmission or yellowness index. Significantly, accelerated and natural weathering have negligible influence on the physical properties of Prolight®, eg. tensile strength, impact resistance. During the life of the sheet natural weathering will leave its thermal or mechanical properties essentially unaltered.
Prolight® exhibits excellent fire performance and in the event of a fire it will soften and open, allowing smoke, heat and gases produced by the fire to escape. This 'venting' property means that damage within buildings can be limited. For details of fire ratings please contact our technical department.
Prolight® has in general excellent resistance to most chemicals; resistance to specific compounds depends on concentration and temperature, duration of exposure and stress within the sheet. Contact with plastic coated metal sheets, wet wood preservatives, solvents and alkali cleaners should be avoided.
Condensation will form on the underside of a roof made from any thin sheeting material. To minimise condensation within an enclosed structure, sources of moisture should be minimised and good ventilation should be provided.
Prolight®, is manufactured under Quality Management Systems registered to BS EN ISO 9001:2000 by Brett Martin as MarlonCS Longlife. The sheet carries a 10 year Guarantee in respect of light transmission and a 3 year Guarantee in respect of weather breakage.
Isolation from plastisol coating
Plastisol coating on roofing sheets is aggressive to polycarbonate. It is essential that the lapped area of metal sheet at either side of and at the lower end of the polycarbonate rooflight has an aluminium foil adhesive tape applied to completely isolate the polycarbonate from the plastisol-coated metal.