As codes and standards evolve towards low or net-zero energy buildings, the practicality of achieving these targets in high-rise concrete construction gets increasingly challenging. High-rise residential buildings are becoming more common as cities redevelop and add density. Current design and construction practice for high-rise multi-unit residential buildings (MURBs) presents a number of constraints with regards to achieving high levels of energy performance.
These practice issues typically include;
- Desire to maximize glass to enhance marketability, daylight, and views;
- Desire to provide access to the outdoors via extended balconies;
- Need for Code-mandated non-combustibility and life safety requirements;
- Preference for building systems that minimize exterior construction access and streamlines construction sequencing;
- Adoption of increased structural load requirements, and/or
- Drive to minimize initial capital costs.
The outcome of these combined constraints is often poor energy efficiency, with the burden of higher operating costs deferred to future owners. There has been significant industry discussion on the poor energy performance of this class of building but there is very little guidance or long-term factual strategic information beyond broad principles of minimizing glazing areas, maximizing glazing performance, increasing air-tightness, and adding more insulation to opaque areas. This paper explores the prospect of energy-use becoming a primary consideration in high-rise residential buildings and what that will likely mean for the typical competing constraints mentioned above.