BRE DG489 PDF

There is a little information and no authoritative guidance about wind loads on roof-based photovoltaic (PV) systems available to the designer. In the UK, determining wind loading on PV systems and their component parts tends to be based on experimental data, extrapolation of wind loading data intended for other building elements, or from design guidance for PV installations in other countries where the wind loads or construction practice can be quite different. This gives rise to a wide range of design wind loads and, sometimes, potentially unsafe designs. This Digest reviews the wind loading information appropriate for roof-based PV systems and gives recommendations and guidance for the design of roof-based PV systems for wind loads. It covers both PV tiles or slates integrated into pitched roofs and PV modules mounted on or above pitched roofs. It has been developed from work undertaken during a Partners in Innovation project funded by the DTI.