By Marley Eternit

1. Check compliance with the latest legislation. Tiles you select will help the building comply with Building Regulations on energy usage, fire safety and resistance to moisture. Also check if the local authority requires planning permission.

2. Check the local exposure and topography. BS8104 Code of Practice for Assessing Exposure of Walls to Wind-driven Rain and BRE 262 Thermal Insulation: Avoiding Risk divides the UK into two exposure zones, which may influence the tile you need.

3. The shape and structure of your roof will determine the type of tile. For example, if the roof contains a hip or a valley, the pitch will be reduced by 5-10° or more, making it more vulnerable to the elements.

4. Select the right underlay. This can either be supported or draped, and must be of adequate strength, durable and stop water penetration. Draped underlay must also be able to withstand wind lift. See the Code of Practice for Slating and Tiling (BS 5534).

5. Consider the fixing specifications. These will vary depending on the type of tile and the pitch of the roof. Consult the Code of Practice for Slating and Tiling (BS 5534) for further information, or roof tile manufacturers should be able to offer advice.