Masterplanning for Wind - Surviving Implementation

Posted by
Tahrana Lovlin, MAES, P.Eng.
Microclimate Specialist
Guelph, ON, Canada

Masterplanning and Pedestrian Comfort

Master planning is step one in development. Sometimes it’s done through secondary plans, or subdivision plans. Whatever it is labelled, it is intended to be holistic and all encompassing. In this era where pedestrian usage is emphasized and encouraged, the best plans can be destroyed if Mother Nature is not taken into account.

Pedestrian comfort is based on many things, but one key component is wind. If you cannot comfortably stand in a park, sit at a café, or walk down an animated streetscape due to wind, then people will not use the spaces and the best intentions of the design team will be lost.

While pedestrian comfort can be achieved through building design (perhaps with significant compromises), the master plan is the most effective time to consider how wind will influence pedestrians and outdoor amenity spaces.

Where to begin…

Well, every site plan I’ve ever reviewed includes information about the prevailing winds. But how should you use this information? What to do depends on your local climate. In some areas of the world (say, north of the 30° parallel), the desire is to decrease exposure to strong winter winds; in other parts of the world (between 30° north and 30° south), you want to increase exposure to all wind in order to provide relief. Once you determine where you are, and how important pedestrian comfort is to the success of the master plan, then you can start making decisions.

Let’s consider overall layout of massing first. It can be approached three ways for those areas where winter winds are a concern:

Approach #1: Place the tallest buildings on the upwind side of the site, where they can provide protection for rest of the site.

If you do this, you’ll need to worry about the channeling of strong winds between the buildings, which means you won’t want amenity spaces in the vicinity. But it gives your overall site some protection.

Approach #2: Place the shortest buildings on the upwind side and then gradually build up height to the centre.

The aim here is to gradually direct the wind up and over the site.

Approach #3: Keep all buildings the same height (or within three storeys of each other).

This creates a uniform mass, where no building can redirect wind down to grade. Amenity spaces between the buildings should be fairly calm, depending on road alignment.

img