Airtightness is critical to a building’s overall performance. By wrapping our buildings with an airtight enclosure, we minimize the influx of unwanted pollutants while retaining as much filtered and conditioned indoor air as possible. An airtight building is important to achieving our firmwide goals of climate, health, and equity.
- Airtight design allows the thermal enclosure to reduce HVAC loads and thus conserve energy from what is typically a building’s largest energy end-use, space conditioning. Insulation alone does not keep heat on the desired side of an enclosure; air leakage infiltration and exfiltration is a primary path for heat and moisture transfer through the building envelope.
- Airtight design allows us to have quality control over indoor air. The tighter a building, the higher percentage of ventilation air is intentionally introduced through a filtration system. A leaky building allows more outdoor air to bypass these filters, bringing untreated outdoor pollution into the indoor environment.
- Airtight design neutralizes outdoor conditions, allowing building systems, rather than happenstance, to determine indoor environmental air quality. Therefore, a tight building in a polluted area can be just as safe as a building in a pristine environment. The same cannot be said for a leaky building.
Airtightness is not “applied sustainability,” but the effective execution of technical design and construction strategies. The skills and efforts that lead to tight buildings add value for our clients and building users. Along with attention to detail and extensive field testing, we achieve very tight buildings through the following strategies:
- High-performance windows and curtain wall systems
- Collaborating with contractors to get the details right
- Using mock-ups to fine-tune the details and performance
- Frequent site visits by third-party reviewers to catch and correct installation mistakes