In December 2003, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) published Standard 62.2, “Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings.” The standard was met with much controversy, mainly from industry groups that questioned whether specific links could be made between ventilation rates and health risks, as well as whether the standard would limit certain types of equipment.
One of the key recommendations made by the standard was that whole-house ventilation be utilized in order to dilute pollutants generated by people, processes, and materials. For an average-size house, the standard recommends between 45 and 75 cfm of continuous mechanical ventilation, while smaller homes need less ventilation and larger homes need more.
This was revolutionary thinking in an industry that was convinced that operable windows and leaky building envelopes would provide enough ventilation for most homeowners. Once the dust settled and the standard was put into practice, manufacturers responded with many new products designed especially to meet the ventilation recommendations of Standard 62.2.
WIDESPREAD ADOPTION
It is no longer a question whether or not Standard 62.2 will be adopted by various municipalities around the country. All green building programs require adherence to Standard 62.2, and many states, including Minnesota, Washington, Alaska, and Oregon, have ventilation requirements very similar to the standard. Numerous local codes have also adopted all or part of the standard, and California will be adopting it in 2008 and New York in the very near future.However, it is not simply the standard that is requiring dealers to install better ventilation systems. Homeowners have become very aware of the IAQ in their homes, and they are insisting on new and better products that will help them breathe easier.
As Kathie Perry, director of marketing, Fantech Inc., noted, “We’ve all seen indoor air quality become an increasingly important topic to homeowners over the last few years. Price objections to systems that improve indoor air quality are no longer an issue. If homebuyers are willing to pay thousands for decorative items like granite counters or faucets, the minimal added expense for better indoor air quality for their families seems of little concern.”
As a response to Standard 62.2 and homeowner demand, Fantech introduced its Ventech programmable controls for inline fans, which were created to provide a cost-effective way for builders to meet the requirements of the standard.
The system works well in bathrooms where an inline fan can play the dual roles of local high-volume exhaust on demand and continuous or intermittent low-volume ventilation to the rest of the house. The Ventech controls feature a high-speed boost button, which enables high-volume output for 20 minutes before returning to the low-volume output selected to meet the continuous ventilation needs.
“Fantech’s range of inline fans and accessories allows flexibility in the design of a ventilation system,” said Edmund Murray, engineer, Fantech. “The combination of an inline fan, exhaust grilles, and electronic wall controls makes for a very simple to install ventilation system for new construction and existing homes.”
David Miller, sales and product manager, Fantech, noted that the company’s HRVs and ERVs also comply with Standard 62.2 and provide improved air quality, comfort, moisture control, and energy efficiency.
VARIETY OF PRODUCTS AVAILABLE
Broan-NuTone LLC has also designed numerous products to help contractors and builders meet Standard 62.2. On the local exhaust side, the company has many ventilation fans and range hoods that will easily meet the local exhaust/source control portion of the standard, said Thomas Heidel, marketing manager - indoor air quality, low-voltage, and controls, Broan-NuTone.“For example, the SmartSense System is an affordable ventilation solution that utilizes Broan Ultra Silent fans located in bathrooms, laundry rooms, and elsewhere to provide local exhaust as well as whole-building continuous ventilation,” he said.
The SmartSense fans communicate over existing power lines in the house to create an integrated whole-building ventilation system for the home. The whole-building ventilation requirement, which is based on the size of the home in square feet and the number bedrooms, can be entered into any of the SmartSense fan controls. The system then monitors normal/manual operations of ventilation fans and deducts that amount of ventilation from the total needed. If necessary, the system will automatically operate individual fans throughout the home to provide recommended ventilation.
Broan-NuTone also offers a full-line of HRVs and ERVs, which provide balanced ventilation while transferring heating or cooling energy from the exhausted stale air to the fresh incoming air. A line of heat and energy recovery air exchangers that provide HEPA filtration of the incoming and existing air in the home is also available.
As with any other heating or cooling system, proper installation is the key to optimal performance. The ductwork must be pulled straight with a minimum of elbows and bends to ensure proper operation of the ventilation fan. And when using balanced air exchangers, it is important to locate the fresh air intake away from harmful exhausts from furnaces, dryers, water heaters, and plumbing vents.
While most homeowners understand the importance of good IAQ, there will always be some who balk at the added cost of ventilation products. For those folks, contractors should take the time to explain how VOCs from solvents, paints, and other materials can build up in a home and how a ventilation system can help eliminate those factors in order to maintain a healthy home. Humidity and carbon dioxide will also contribute to poor IAQ and increase the risk of respiratory and other illnesses.
For those homeowners who are concerned about the amount of energy that will be consumed by a whole-house ventilation system, their fears can easily be put at ease. There have been numerous improvements made in the energy consumption of residential ventilation products over the last few years, and most manufacturers are very proud to be able to say their fans are Energy Star-qualified.
With all the new products available, there’s no reason why most homes can’t be constructed or retrofitted to meet the ventilation recommendations in ASHRAE Standard 62.2. There’s a cost-effective solution for just about every homeowner, and it is up to contractors to make sure their customers have the systems they need to breathe easy.
Publication date:10/22/2007