Weight: A clad over roof will often prove too heavy for any existing frames due to it possessing heavy timber, insulation materials and tiles. It is imperative that any new roof for an old conservatory is lightweight. The lightest solid roof systems weigh around 31KG/M ².
Tip: Always ask your installer for the total unit weight of the new roof per Sq.M
Fire Safety: Another issue with ‘clad-over’ systems is that they don’t comply with current fire regulations as they are not effectively fire tested as a complete roof structure, which is essential for meeting this part of building regulations. The original structure varies from job to job which means that only individual components could have been tested. Solid roofs must be classified as AC, AB or AA in accordance with BS476-3.
Tip: Ask to see the fire safety certificate of the entire roof system before you commit to the project.
Building Regulations: You’re unlikely to receive Building Regulations Approval for a clad over system because of its low thermal value or structural integrity. Please, don’t confuse building regulations approval with planning permission as they are not the same thing. You will have to inform Building Control if you want to alter a structure (including replacing a glass or polycarbonate conservatory roof with a solid roof). When approval is granted, it proves that the new roof is structurally sound.
Tip: Check that local Building Control has been informed before the conversion starts. Obtain a Building Regulations ‘Final’ Certificate and file it in a safe place.