A Naturally Ventilated House in the Pacific Northwest
All historic buildings were ventilated naturally, although many of these have been compromised by the addition of partition walls and mechanical systems. With an increased awareness of the cost and environmental impacts of energy use, natural ventilation has become an increasingly attractive method for reducing energy use and cost and for providing acceptable indoor environmental quality and maintaining a healthy, comfortable, and productive indoor climate rather than the more prevailing approach of using mechanical ventilation. In favorable climates and buildings types, natural ventilation can be used as an alternative to air-conditioning plants, saving 10%-30% of total energy consumption.
The Pacific Northwest – running from Vancouver B.C. to Seattle, WA and down to Portland, OR is an ideal climate for natural ventilation strategies. The limited number of overheating days, cool nights and reliable breezes establish a framework for keeping buildings comfortable without mechanical air conditioning.
The building form becomes the primary strategy for a successful naturally ventilated building. The BLK_LAB Residence in West Seattle optimizes this approach. A narrow building foot print is the first step, allowing for cross ventilation to effectively access all areas of the house. The next step is centrally locating a vertical shaft that connects all levels of the building section (in this case the stairwell). The vertical shaft created a ventilation chimney (stack ventilation) that utilizes the stratified air to draw the warm air out of the top of the structure and promote air circulation throughout.