The wind resource available over tall buildings can be significant, even in urban areas. However, the potential for power generation from wind turbines mounted on tall buildings is often not realised due to inappropriate siting of the turbine. The lack of information available to building owners about siting of turbines in these situations prompted BRE to carry out a wind tunnel study to measure the wind characteristics over a range of common building forms. This Information Paper presents some simple rules for siting wind turbines on tall buildings in order to maximise the power output. 8 pages. Contents Introduction Building models Wind velocity measurements Variation in wind conditions with height above the roof Conclusions - Other considerations regarding wind turbine installations on buildings References