Weight: A problem with clad over solution is they are often too heavy for existing frames as they use heavy timber, insulation materials and tiles. It is crucial that an old conservatory’s roof is replaced with a lightweight roof. 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: A ‘clad-over’ system does not meet present fire safety regulations due to it not being fire tested as a complete roof structure, which is essential to satisfy part of the building regulations. It could be the case that only specific components have been tested because the original structure varies by each job. Solid roofs must be defined 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: Clad over systems often fail to get Building Regulation Approval. This is down to their low thermal efficiency and structural integrity. Do not confuse this with planning permission as they are very different. YYou must notify Building Control when making a change to a structure, such as replacing a glass roof with a solid roof, in order to check that the roof is physically 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.