Designing Parking Facilities in a Changing Climate

Tuesday, August 12, 2014

Parking facilities are being redesigned to minimize the Urban Heat Island Effect and to efficiently manage storm water. Climate change is occurring in Canada and throughout the world, affecting our public health and our overall quality of life.

By Julie Guicheteau, Engineer, Environmental Services, City of Montreal

As part of our efforts to limit the effects of climate change, we need to rethink the design of our public infrastructures. 

In February 2013, le Bureau de normalisation du Québec (Quebec Standards Bureau – BNQ) issued a new standard: BNQ 3019-190 Lutte aux îlots de chaleur urbains – Aménagement des aires de stationnement – Guide à l’intention des concepteurs (Countering the Urban Heat Island Effect in Parking Lot Development – A Design Guide). This new standard provides a series of practical guidelines to minimize the creation of urban heat islands and to efficiently manage storm water in the design and construction of parking facilities. The content is specifically directed to the design, redesign and renovation of large and small off-street parking lots.

Photo : example of green parking facility, City of Beloeil (source : conception Alain Baillargeon, Objectif paysage).

The new standard includes measures to:

  • Diminish the surface area dedicated to parking by decreasing the actual size of the parking lot, reducing the number of parking spaces and decreasing the size of individual parking spaces;
  • Revegetate parking lots and their surroundings by preserving existing green spaces and creating new areas of greenery (notably through the use of broad-crown trees, creating more shade over the parking lot, which has a cooling effect, and the use of green roofs and living walls);
  • Manage storm-water on site by direct infiltration into the ground and the use of permeable surfaces, and by building above-ground or below-ground storm-water catchment zones;
  • Promote the use of materials with a high Solar Reflective Index (SRI) and highly permeable materials, especially for areas where shade cannot be provided and areas that receive more direct sunlight, including roadways.

The standard performance criteria used to evaluate parking lot climate change suitability are the percentage of shade areas; the SRI; and the percentage of permeable surfaces.

This standard will help benefit a broad range of design professionals, including engineers, urban planners and landscape architects, as well as organizations such as municipalities, government agencies and departments, non-profit organizations, parking lot owners and operators.

The standard was produced by the BNQ in keeping with the International Rules for Consensual Standards Development issued by the International Standards Organization (ISO). It has been submitted to public consultation to obtain informed advice and comments from design experts and likely end-users. It was edited and approved by a panel of professionals and public stakeholders with extensive experience in the field of parking facilities design.

For additional information or to download a copy of the BNQ 3019-190 Standard, visit http://www.bnq.qc.ca/fr/normalisation/environnement/lutte-aux-ilots-de-chaleur-urbains.html. This page also includes a brief video summary of the standard.

Parking lot owners and operators can take this initiative one step further by encouraging employees to use alternative means of transportation other than the solo automobile, such as providing secure bike parking facilities, showers, preferred parking privileges for car-poolers, eliminating free parking and refunding public transit expenses. These types of measures reduce greenhouse gas emissions (GHG) and the need for additional parking. In combination, such measures can lead to the repurposing of parking lots into green spaces, where the addition of new trees can offset GHG emissions.