Tighter multifamily buildings make need for proper air ventilation more critical
The air tightening of multifamily buildings around the world has made proper ventilation systems a more critical part of those structures. Without them, air quality, the structures themselves and, most importantly, the occupants inside, suffer.
It used to be that exhaust fans and normal drafts were enough to keep air flowing throughout a building.
“Now that those buildings are built tighter and tighter, those systems don’t work anymore,” said Aubrey Gewehr, design engineering manager for Zehnder America. You need a balanced system to take air out and bring it in.”
A population shift toward urban areas has fueled growth in the construction of multi-family dwellings -- there were 355,000 new multifamily buildings constructed in 2014, according to the U.S. Census Bureau. At the same time, growth in the production of high-performance structures has led to such buildings being tight to boost efficiency and sustainability.
When it comes to existing structures, efficiency tends to be subpar. The U.S. Department of Energy estimates that most older buildings in the United States today are plagued with energy waste, inadequate indoor air quality and comfort issues related to poor exhaust.
Ventilation is much of the focus at this week’s International Air-Conditioning, Heating, Refrigerating (AHR) Exposition in Orlando. The annual event, held from Monday through Wednesday and considered one of the world’s largest HVACR marketplaces, spotlights new/future products and trends within the industries, including a number of seminars aimed at helping everyone from building managers to solution deployers capitalize on sustainability and efficiency.
As part of the indoor air quality (IAQ) movement and in response to notably increased building envelope performance, more and more ventilation solutions are being seen at conventions such as AHR.
Among them are a fabric end-air duct/dispersion system that replaces traditional ductwork, insulation, diffusers and air valves by providing even air distribution, improved energy efficiency, streamlined installation and reduced maintenance; and a combined louver/damper with drainable 45-degree fixed exterior-facing blades and adjustable interior-facing blades with seals that can be completely closed, offering superior resistance to weather infiltration.
Zehnder is one of the companies that will be showcasing its line of heat and energy recovery ventilators.
Proper ventilation prevents a host of dangers:
- Moisture buildup that can, over time, weaken the structural integrity of the building.
- Mold development that can trigger disease among occupants and render building unlivable.
- Carbon monoxide spikes that can lead to headaches, dizziness and nausea.
With residential projects, builders and owners tend to be focused on the need and value of proper ventilation as part of the home’s overall efficiency. That same mindset isn’t always at the forefront among those residing in multi-family structures – structures they don’t own and structures where they might only live for a short time.
In a lot of cases, those occupants tend to use standard chemicals for cleaning and outfit the living space with furniture and belongings containing volatile organic compounds (VOCs) that easily can get trapped in the residence, Gewehr said. That punctuates the need for an effective ventilation system, where occupants live as normal while building owners set and manage the ventilation approach to ensure good indoor air quality.
The key to any ventilation effort is ensuring the building has a means of exchanging in good air from other interior or outdoor areas with poor air.
“A decentralized ventilation approach (an HRV for each apartment) coupled with good compartmentalization between apartments make (the residence) less prone to odor and noise infiltration,” Gewehr said. “If a neighbor is smoking a cigar, you’re not smoking a cigar. Areas are well-sealed from each other, and it ends up being a more enjoyable atmosphere for the tenants.”
Topics: Automation and Controls, Building Owners and Managers, Ceilings, Construction Firms, Energy Recovery & Heat Recovery Ventilation, Energy Saving Products, Engineering Firms, HVAC - Heating, Cooling, and Ventilation, Indoor Air Quality (IAQ), Interior Design, Interiors, Multifamily / Multiunit Residential, Paint - Low & No VOC, Sustainable Communities, Technology, Urban Planning and Design, Ventilation
Companies: Zehnder America