A new Urban Land Institute (ULI) Report entitled “Scorched” provides new insights on how increasing urban temperatures are impacting the real estate community. Most notably, it makes clear that increasing temperatures, while a concern everywhere, are a greater concern in urban environments. In fact, the “Urban Heat Island” effect is the cause of most temperature rise in US cities. Urban areas are 2-6 degrees warmer than surrounding areas and temperatures are rising 50% faster than non-urban areas. Fortunately, the report provides practical guidance, as well as case studies, demonstrating how we can address this issue using well understood design techniques and technologies, one of which is dynamic glass.
Some Fast Facts
Many people have experienced the urban heat island effect firsthand, so there is no need to convince people it’s real. The question is how significant is it? The figures cited above provide strong data, but there’s more:
- Urban heat islands increase building’s peak cooling loads by 13%. Since peak load significantly impacts HVAC costs, this means urban heat islands are adding to the upfront cost of a building.
- 20% of urban smog formations are due to heat islands. This results in localized air quality issues.
- 2018 was the 4th hottest year on record globally. This one speaks for itself.
These data points show that concern over extreme heat is not an issue for tomorrow but one we need to contend with today.
What’s at Risk
The list of potential impacts is long, but among the most notable are human health and safety, building longevity, operating costs and economic performance (think retail traffic, tourism etc.) and even real estate value. This last point may raise some skepticism, but it is not farfetched. Imagine a zip code in a dense urban area, one which commands some of the highest rental prices in a given city. Now imagine the market begins to see more warnings on their smartphones of localized air quality issues when the smog index is too high. Or future tenants start looking at energy costs and see that they are higher in dense, high-value areas than others. Worse still, entire markets may get a reputation for having a multitude of heat related issues, causing businesses to look elsewhere for workspace. In its 2018 sustainability plan the City of Cincinnati sees its future as a “climate haven” for people and businesses looking to vacate areas that have become too hot. One city’s risk is another’s opportunity.
How We Respond
The report rightly notes there is no one-size-fits-all technique for mitigating urban heat islands, or responding to their effects. However, focusing on certain key categories of both mitigation and adaptation strategies can provide useful guidance for designers and developers looking to future proof their investments. Mitigation approaches, ways to reduce to heat island effect, need to come at both the urban planning and individual project design level. As with most elements of urban planning, it should be expected that future permitting will be tied to a demonstration of how a given project supports heat mitigation.
Key mitigation and adaptation categories at the building/site level include:
- Building design: orientation, shape and massing
- Building materials and engineering: multiple measures are called out, including dynamic glass. By preventing more heat gain than any conventional glazing product, and by responding intelligently to local climate conditions or building management systems, it is among the adaptive systems that can help manage extreme heat conditions.
- Light colored and reflective surfaces: cool roofs, walls and pavements
- Green infrastructure: green roofs and walls
- Operational changes: thermostat control and temperature modifications
- Here again, dynamic glass can be used for localized comfort control without the need for adjusting mechanical heating/cooling.
These are just the recommendations for buildings, a great deal is needed at the district level as well. This is important to remember, since the real estate community as a whole is truly in this together. Preventing the negative impacts of urban heat islands for occupants, and assets, is a shared responsibility. The good news is that the techniques and technologies needed to design better are available today. It is up to all of us in the real estate community to use them.