City of London issues planning wind guidelines to keep cyclists and pedestrians safe near skyscrapers

The City of London Corporation, which governs the financial district in the heart of the capital, has issued the UK’s first planning wind microclimate guidelines in a bid to keep cyclists and pedestrians safe amid the ongoing development of skyscrapers in the Square Mile.

The introduction of the guidelines, which are fully set out in a document at this link, follow concerns that the wind effect created by tall buildings can sometimes destabilise cyclists and even push them into the path of motor vehicles.

Wind tunnel studies and computer simulations, along with testing of roads and footways, will be used to determine the effect of buildings, with the overarching aim of protecting vulnerable road users in line with the City Corporations aim of getting more people cycling and walking.

Drawn up in partnership with Ender Ozkan from specialist engineering consultancy RWDI, the City Corporation says that the guidelines will, among other things:

Require that wind impacts are tested at the earliest point of a scheme’s design development (e.g. height and massing) to avoid the need to retrofit wind mitigation measures

Ensure more micro-level assessments of wind directions is carried out in wind tunnel testing

Apply a new rigorous code of practice in the use of Computational Fluid Dynamics (CFD) techniques

Require the commissioning of two separate consultants, one to carry out wind tunnel testing and the other CFD, and interrogate any discrepancies between both sets of results

Assess the variation of mean and gust wind speed and height.

Alastair Moss, chair of the planning and transportation committee, said: “With the number of tall buildings in the Square Mile growing, it is important that the knock-on effects of new developments on wind at street-level are properly considered.

“These guidelines mark another significant step that the City Corporation is taking to put cyclists and pedestrians at the heart of planning in the Square Mile, prioritising their safety and experience.

“From the Transport Strategy to the City Plan, we are ensuring that our streets are a comfortable and pleasant place to live, work and visit.,” he added.

“We hope these groundbreaking guidelines can create a blueprint for others by delivering safer, more enjoyable streets that meet the evolving needs of this great city.”

The introduction of the guidelines has been welcomed by cycling campaigners.

London Cycling Campaign’s infrastructure campaigner, Simon Munk, told the Guardian that there is a “well-documented risk of concrete canyons … creating wind conditions where pedestrians can be knocked off their feet or cyclists can be pushed sideways into the path of motor vehicles.”

Roger Geffen, policy director for the charity Cycling UK, commented: “Anywhere where a tall building goes up, you find that somewhere you could be previously cycling happily, there is a wall of wind.

“You can suddenly be really struggling. In the rush to put up tall buildings, no one has been thinking about what it means for aspirations to make cycling and walking simpler and safer. It’s great that someone has started now.”