Subject to exemptions, building work is required to be carried out in compliance with the applicable requirements in the Building Regulations 2010, SI 2010/2214, reg 4. In addition, there is a further requirement to apply for approval under the building control regulations (Building Regulations 2010, SI 2010/2214, reg 12). Building Regulations 2010, SI 2010/2214, Sch 1 sets out the requirements for various parts of the building work and government guidance is provided on those requirements by Approved Documents. Building Regulations 2010, SI 2010/2214, Sch 1 requires, along with other requirements, adequate drainage of rainwater. Approved Document H contains guidance on constructing