WIND IMPACT

(Post from Cristina)

Today I will speak about wind... Because i want as many people as possible to know what is behind the buildings that surround us.

Have you ever cycled in a part of town where the downward wind from a tall building has made you come off your bike?

How about walking by a tall building where the wind has thrown you off balance or made it very difficult to walk on a straight line?

To experience the first one, the route between south of Blackfriars bridge and count street has become a challenge on certain winter/ early spring days . The latter, unfortunately, has become a more extended experience in windy days.

Why does this happen?

Well, when you plan a building that is taller than it's context, your building will have an environmental impact in its surroundings. Essentially, and in simple terms, the wind that moves over the rest of the building will be "caught' and pushed down your building towards the ground.

A bit like when you are trying to make a room less noisy , adding texture to your facade will impact it's velocity but sometimes you also need to add canopies above the ground floor or tree lines.

This is why when you plan a tall building, there is an important you need to take... It is called a wind test analysis and it is a very interesting exercise that involves building a model of your building with small perforations in key areas. Then those will be connected to a smoke machine. Then the model will be placed in a controlled environment/tunnel and wind will be blown to test the impact and suggest modifications to ensure safety around the building.

The experiment is very interesting and the report you receive provides advice on both the measuring at ground level and recommendations for mitigation.

If there are plans to build tall buildings around where you live, and you are told at the consultation that tall buildings can be built because other tall buildings have already been approved in the areas, you could ask about the wind test analysis and any mitigation measures.