Building Science Blog Archive

NCHH photo

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.”

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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.

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A bedroom with light blue walls, white window, blue curtains, wooden desk and shelves, gray lamp, blue bed with white pillows, basketball frames, gray carpet, book shelves with books and a red guitar hanging on the wall

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.

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Alden at blower door

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 . . .

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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

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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.

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ZPD illustration

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.

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Double-Duty Exhaust Fans: Good or Bad?

The installation of double-duty exhaust fans in existing dwellings is common. This practice can save money and time on the job and provides a simpler ventilation solution for the occupants. But is it a good idea?

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Infrared R Value tool screenshot trans background-2

Bees Benefit from RED Tool

It’s getting cold in the Sandhills of Nebraska, so Ed Dekleva, a civil engineer, is becoming concerned about the conditions inside his beehives. 

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