Passive House, an ultra-efficient building standard that originated in Germany, has been used for single-family homes since its inception in 1990. Only recently has the concept made its way into the commercial market.
The Passive House standard requires buildings to use at least 80% less energy than a comparable conventional building, so air tightness is a must. The structure must be completely sealed against any air infiltration, at the same time preventing conditioned air from escaping. This means Building Teams must employ multiple layers of insulation in the walls, roof, and flooring, plus continuous air barriers and reliable windows and doors.
Once the building is completely sealed, a number of techniques can be engaged to regulate the temperature. Energy-recovery ventilators may be employed to keep a constant supply of fresh air circulating throughout the home. These heat exchange systems typically recycle the heat of exhaust air from kitchens and bathrooms by filtering it through the fresh air entering from the outside. This saves energy costs.
An analysis of the site and its climate also must also be completed. Effective planning of the window orientation can have a direct impact on the amount of natural daylight that will penetrate the space. Shading devices can be designed to control the amount of sun entering the space at any given time, which can contribute to heat gain.
Passive House enters the hospital sector
The Passive House concept is also spreading to other nonresidential sectors. The machinery and lighting required to run hospitals make them the largest users of energy across commercial sectors. In the Hoechst district of Frankfurt, Germany, a hospital renovation is set to become the first Passive House hospital in the world.
The state of Hesse completed a baseline study to determine the methods for executing such a large-scale PH project. The study notes that ventilation, heating and cooling, water, hygiene, and food service should all be considered when planning building systems around the Passive House standard in a healthcare setting. The study recommends the use of energy-efficient equipment, but notes that many medical devices have not yet been rated for their energy efficiency.
In multifamily buildings, the ratio of interior livable space to building envelope size is greater than that of a single-family home, so the envelope work is somewhat less demanding. Even so, the number of windows, doors, and balconies in multifamily projects means even more areas of the façade are vulnerable to air infiltration and expiration.
Despite these difficulties, commercial Building Teams are rising to the challenge. According to the Passive House Institute U.S., as of June 2014, 21 multifamily projects have been submitted for PHIUS Passive House certification: four have been fully certified, another four have been precertified and are under construction.
Stellar Apartments, Eugene, Ore., was the first multifamily project to achieve certification. Designed by Bergsund DeLaney Architecture & Planning for the St. Vincent de Paul Society of Lane County, this low-income housing project consisted of the construction of two nearly identical buildings.
The first, built to the Eugene Water and Electric Board’s Earth Advantage Standards, was designed to save 15% more energy versus a home built to code. The Building Team designed the second building to Passive House standards. The two buildings have identical floor plans, with six units on two stories, and are oriented in the same direction with similar shading. The main difference between them is the air tightness and the use of an energy-recovery system in the Passive House building.
The buildings were completed in July 2013, and are under study by students at the University of Oregon. The researchers will compare the energy use and cost savings, air quality, light quality, and acoustics of the buildings to determine whether a significant difference exists.
Stellar Apartments in Eugene, Ore., consists of two nearly identical low-income apartment buildings built to different sustainable standards. One meets the city’s Earth Advantage Program requirements, while the other (pictured above and left) is the first multifamily building to achieve Passive House certification. The Building Team included St. Vincent DePaul Society of Lane County (owner), Bergsund DeLaney Architecture & Planning, Hohbach-Lewin Inc., Poage Engineering, and Dougherty Landscape Architects. Photo: courtesy Bergsund DeLaney Architecture & Planning
The Orchards at Orenco is currently under construction in Hillsboro, Ore. Phase 1 of this affordable housing project, owned by REACH Community Development, includes 57 units, making it the largest precertified Passive House building to date.
The facility will employ traditional methods of Passive House construction—a continuous air barrier, extra insulation, and heat recovery system—to achieve up to 90% reduction in energy bills for the tenants. The roof will be light in color to reflect solar heat; it will have a foot of insulation, which is almost four times that required by the local building code.
The Building Team is using triple-pane glazed windows, with European-style tilt-turn operation. It is common for Passive House buildings to use windows made in Europe, as double-hung or slider windows manufactured in the U.S. do not offer the tightness required for PH certification.
Building Teams can apply some of the principles to multifamily projects, regardless of whether they are able to achieve full certification. Extra insulation, greater attention to detail when sealing the building envelope, and energy-efficient heating and cooling systems can have a positive effect on a building’s performance regardless of whether the building is able to carry the Passive House label.
Related Stories
Affordable Housing | Apr 7, 2023
Florida’s affordable housing law expected to fuel multifamily residential projects
Florida Gov. Ron DeSantis recently signed into law affordable housing legislation that includes $711 million for housing programs and tax breaks for developers. The new law will supersede local governments’ zoning, density, and height requirements.
Energy Efficiency | Apr 7, 2023
Department of Energy makes $1 billion available for states, local governments to upgrade building codes
The U.S. Department of Energy is offering funding to help state and local governments upgrade their building codes to boost energy efficiency. The funding will support improved building codes that reduce carbon emissions and improve energy efficiency, according to DOE.
Steel Buildings | Apr 6, 2023
2023 AISC Forge Prize winner envisions the gas station of the future
Forge Prize winner LVL (Level) Studio envisions a place where motorists can relax, work, play, shop, or perhaps even get healthcare while their vehicles charge.
Architects | Apr 6, 2023
New tool from Perkins&Will will make public health data more accessible to designers and architects
Called PRECEDE, the dashboard is an open-source tool developed by Perkins&Will that draws on federal data to identify and assess community health priorities within the U.S. by location. The firm was recently awarded a $30,000 ASID Foundation Grant to enhance the tool.
Architects | Apr 6, 2023
Design for belonging: An introduction to inclusive design
The foundation of modern, formalized inclusive design can be traced back to the Americans with Disabilities Act (ADA) in 1990. The movement has developed beyond the simple rules outlined by ADA regulations resulting in features like mothers’ rooms, prayer rooms, and inclusive restrooms.
Market Data | Apr 6, 2023
JLL’s 2023 Construction Outlook foresees growth tempered by cost increases
The easing of supply chain snags for some product categories, and the dispensing with global COVID measures, have returned the North American construction sector to a sense of normal. However, that return is proving to be complicated, with the construction industry remaining exceptionally busy at a time when labor and materials cost inflation continues to put pricing pressure on projects, leading to caution in anticipation of a possible downturn. That’s the prognosis of JLL’s just-released 2023 U.S. and Canada Construction Outlook.
Cladding and Facade Systems | Apr 5, 2023
Façade innovation: University of Stuttgart tests a ‘saturated building skin’ for lessening heat islands
HydroSKIN is a façade made with textiles that stores rainwater and uses it later to cool hot building exteriors. The façade innovation consists of an external, multilayered 3D textile that acts as a water collector and evaporator.
Market Data | Apr 4, 2023
Nonresidential construction spending up 0.4% in February 2023
National nonresidential construction spending increased 0.4% in February, according to an Associated Builders and Contractors analysis of data published by the U.S. Census Bureau. On a seasonally adjusted annualized basis, nonresidential spending totaled $982.2 billion for the month, up 16.8% from the previous year.
Sustainability | Apr 4, 2023
ASHRAE releases Building Performance Standards Guide
Building Performance Standards (BPS): A Technical Resource Guide was created to provide a technical basis for policymakers, building owners, practitioners and other stakeholders interested in developing and implementing a BPS policy. The publication is the first in a series of seven guidebooks by ASHRAE on building decarbonization.
Sustainability | Apr 4, 2023
NIBS report: Decarbonizing the U.S. building sector will require massive, coordinated effort
Decarbonizing the building sector will require a massive, strategic, and coordinated effort by the public and private sectors, according to a report by the National Institute of Building Sciences (NIBS).
