Context

The provisions governing microclimatic impacts are drawn from the following statements presented in Part I of the Master Plan :

• Action 12.1 : Promote quality architecture that is ecologically sound and respectful of Montréal’s character.

These provisions also aim more specifically to :

• Improve comfort for pedestrians in public spaces (streets, parks, plazas and squares) by limiting the impact of structures on wind and sunlighting.

Provisions

5.5.1 Impacts on sunlighting

• Borough by-laws must require that a structure that is half again as high as the average height in metres of buildings situated within a 50-metre radius, in a zone or zoning area where a height equal to or greater than 23 metres or greater than 6 storeys is authorized, take into account its impact on the natural light and sunlighting of neighbouring residential properties as well as the sunlighting of streets, parks and public places. In calculating average height, buildings not in compliance with height limits established in borough by-laws are excluded.

5.5.2 Impacts of wind

• Borough by-laws must require that a construction that is half again as high as the average height in metres of buildings situated within a 50-metre radius, in a zone or zoning area where a height equal to or greater than 23 metres or greater than 6 storeys is authorized, must :
  • Tend not to generate any wind impact whose average speed at ground level, calculated on an hourly basis, is greater than 15 km/h in the winter and 22 km/h in the summer and not exceed this speed for more than 25% of the time in a public thoroughfare and 10% of the time in a park or public area;
  • Tend not to generate gusts of wind at ground level whose speed exceeds 75 km/h at ground level for more than 1% of the time. The reference period for evaluating gusts of wind must be 2 seconds or less, with a turbulence of 30%.
• In calculating average height, buildings not in compliance with height limits established by borough by-laws are excluded.