Building Science Blog Archive

ASHRAE 62.2 Morsels
As a fifteen-year member of the ASHRAE 62.2 committee, I am often asked about the more difficult or contentious details of the 62.2 standard. These questions range from how to measure dwelling height, should the basement be included in the floor area, or how to determine the airflow rate of balanced ventilation. This is the first of two articles including a collection of these questions from users of the 62.2 Standard and the RED Calc 62.2 tools, along with my best answers.

Best Practices for Residential Ventilation
Ventilation installation practices are usually based on ASHRAE 62.2 in the U.S., the only question being which version of this standard is used by the relevant program. ASHRAE 62.2 is a minimum standard, not a best-practice standard. As a fifteen-year member of the ASHRAE 62.2 committee, I am often asked about the best ways of exceeding the 62.2 standard for good indoor air quality.

Major Study Shows ASHRAE 62.2 Ventilation Works!
A significant research report published in April of this year by the National Center for Healthy Housing (NCHH) found that subsidized multifamily housing with ASHRAE 62.2-compliant ventilation had better indoor air quality than housing without 62.2-compliant ventilation. This important research states: “Levels of four of the five indoor contaminants improved substantially with [continuous] mechanical ventilation.”

Core Sampling Cellulose Insulation Density
It is often useful to be able to determine the installed density of dense-pack cellulose in a wall. Because the installer must work without the benefit of viewing the coverage or density, core sampling was devised many years ago to measure these important metrics. If the density is too low, the R-value and air leakage degrade. If the density is too high, insulation and labor are wasted.

Better Sleep Leads to Sweeter Building Science Dreams
Sleep is vital to our health, including our immunity from disease, heart function, and even reproductive vitality. A bad night’s sleep might contribute to poor performance at work and a sour emotional state the next day. It is difficult to assign a cost to a bad night’s rest, but I think most of us agree that it’s a cost we would rather avoid.

The Great Ramp Up of Weatherization
The last 15 months have caused many of us to wonder if we will experience business-as-usual ever again. We have been restricted or prevented from visiting customers’ homes. When it has been permissible to visit a home to conduct an energy audit, complete a . . .

ASHRAE 62.2 Alternative Compliance Path
62.2 Compliance Paths1 ASHRAE 62.2 has two compliance paths for sizing dwelling-unit ventilation. Normal compliance may be used for new or existing dwellings, whereas alternative compliance may be used

Air Leakage Metrics, A Rising Star
As new and existing buildings become tighter as a result of our attempts to save energy and slow global climate change, the ability to measure building tightness and convert the tightness to a useful metric becomes more important.

Effective Zone Pressure Diagnostics
Zone Pressure Diagnostics (ZPD) can be a useful and effective tool for determining the effectiveness of a designated pressure barrier. What can you do to increase the accuracy – or reduce uncertainty – of your results? Following these simple rules will help you hit your target.