News: Regulatory Requirements for a Green Roof Installation
Planning permission should always be sought for any roof replacement and regulatory requirements will differ according to borough council, area building constraints and the size of the project.
As a green roof is generally perceived as the roof covering and not structural, standard building regulations contain no direct references to green roofing. Regulations will concern the roof structure and weight-carrying capacity as a general rule of thumb. Green roofing is increasingly encouraged in urban areas by local authorities around the UK, although it is usual for permission to involve neighbouring properties to be informed of your plans for approval.
There is a ‘Green Roof Code’, compiled as a guide by collaboration between the Green Roof Association (GRO) and the Environment Agency. Intended as a code of best practice, the guide offers advice for construction and density of each layer. A copy of the guide can be downloaded here.
A green roof will require a sturdy structure to carry the extra weight of a fully waterlogged, mature coverage - calculated at approximately 150kg per square metre. Once the structure is approved, then work can begin on the surface. Maintain drainage, insulation and waterproofing regulatory requirements as you go to ensure that there are no problems once the work is completed.