Our roof domes are injection moulded from tough, impact-resistant polycarbonate, TP(a)-rated, and incorporating UV screening up to 380 nanometers to prevent discolouration from solar radiation. A BBA Certification confirms that the SolaMaster roof dome is classified as Tp(a) rigid in accordance with UK building regulations which means, unlike acrylic/PMMA domes, it may installed without restriction and in multiples on any UK roof.