Technically Speaking: Not All Insulation is Graded Equally

About a year ago, I worked along with other HERS raters and the North American Insulation Manufacturers Association (NAIMA, a.k.a. Insulation Institute) to conduct a study on the importance of insulation installation quality and grading.

RESNET, the nation’s leading home energy efficiency network and the governing body of the Home Energy Rating System (HERS® Index) established standards for grading insulation installation.

The grading is as follows:

Grade I— the best and nearly perfect install which includes almost no gaps or compression… what some would call “G.O.A.T.”
Grade II—allows for up to 2% of missing insulation (gaps) and up to 10% compression over the insulation surface area… what some would call “mad decent”.
Grade III—insulation gaps exceed 2% and compression exceeds 10%… anything worse and the insulated surface area is considered un-insulated.

RESNET Insulation Diagram

Source: RESNET Mortgage Industry National HERS Standards

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Tech Notes: Universal Design v. Accessible Design

“Isn’t Universal Design just a different term for Accessible Design?” We hear this from architects and designers a lot. While similarities exist, Accessible Design and Universal Design are actually quite different.

outlets, switches, env controls

This image depicts the prescriptive Accessible Design requirements for light switches and operable parts under the Fair Housing Act. Unlike Universal Design, Accessible Design is not intended to be flexible, with little or no room for tolerance.

The term “Accessible Design” typically refers to compliance with Federal accessibility laws and state and local building codes; including the Americans with Disabilities Act and the Fair Housing Act, among others. Accessible Design requirements are based on anthropometric research – or the study of the human body – and are intended to address people with disabilities. Laws and codes that require compliance with Accessible Design requirements include little or no room for tolerance.

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#UnfreezePA: SWA at the Helm of the PA Icehouse Demonstration

On Tuesday, June 6, 2017, leaders of Pennsylvania’s clean energy movement took to the steps of the State Capitol Building. The cause? To demonstrate just how much room PA State Energy Codes have to improve. Amidst a cohort of speakers and presenters, USGBC’s Central Pennsylvania chapter erected two sheds, each filled with 1,080 pounds of ice: one built to 2009 Code requirements, currently in place under PA state law; and the other built to Passive House standards. Over the course of the month of June, the public will be able to watch as the respective blocks of ice melt within their structures. Ultimately, the difference in the rate of ice melt between the Code House and the Performance House (Passive House) will illustrate the degree to which current energy laws and codes are lacking, while simultaneously offering a model for advancement.

Code Icehouse 3pm 6/14

Performance Icehouse 6/14

In 2009, the International Energy Code Council (IECC) developed energy-saving standards that were adopted by most U.S. state governments. While the 2009 Code was widely instituted in the period following its publication, several states have since embraced even more efficient requirements that are quickly replacing outdated terms. For instance, the state of Maryland – comparable to Pennsylvania in terms of climate, population, and demographic spectrum – is operating under requirements equivalent to 2015 IECC standards.  New York, New Jersey, Massachusetts and Vermont are other states in the same geographic region and general climate zone that have opted towards more energy efficient codes.[1]

Passive House, on the other hand, is a set of design principles that aim to attain a “quantifiable and rigorous level of energy efficiency within a specific quantifiable comfort level.[2]” More simply, Passive House projects go above and beyond the statutes of any enforced codes to follow a “maximize your gains, minimize your losses” approach to building design. The Passive House Institute of the United States (PHIUS) provides the following summary of Passive House principles: Read more

Tech Notes – Drinking Fountain Height

Where the 2010 ADA Standards apply, 100% of drinking fountains must comply with criteria for accessible drinking fountains found at Section 602. Of those, 50% must have spout outlets located 36 inches maximum AFF to provide access for individuals in wheelchairs (ADA Section 602.4). The remaining 50% must have spout outlets between 38 and 43 inches AFF to provide access for standing persons (ADA Section 602.7). A Hi-Lo drinking fountain satisfies requirements for both standing (Hi) and seated (Lo) persons.

Where there are an odd number of drinking fountains, the odd numbered drinking fountain is permitted to comply with criteria for seated or standing persons. For example, if there are a total of 9 drinking fountains; 4 can comply with criteria for seated persons, 4 can comply with criteria for standing persons, and the 9th one can comply with criteria for either seated or standing persons. As always, be sure to check local code requirements that apply in addition to the 2010 ADA Standards.

Heat Pumps Are Taking Over

Air-source heat pumps are a booming business. In the Northeast, manufacturers report that sales of residential systems have increased by 25-35% per year over the past 5-10 years. We’ve seen more and more systems being installed in existing homes (to provide cooling while offsetting oil or propane used for heating) and into new homes (often as the sole source of heating and cooling).

We’ve looked into these systems often, and from many perspectives. I’m planning a series of posts, but, for now, here are the answers to some basic questions we receive from clients.

First, the basics: What is an air-source heat pump (ASHP)?

It’s an air conditioner that can operate in reverse. During the summer, it moves heat from indoors to outdoors. In the winter, it moves heat from outdoors to indoors. We helped NEEP (the Northeast Energy Efficiency Partnerships) to put together a market assessment and strategy report on ASHPs. The early sections in this document (see p. 12) outline the different terms and types of heat pumps (ducted/ductless, split/packaged, mini-split, multi-split, central, etc.) Unfortunately, different people can use the same term to mean different things, but hopefully the NEEP Northeast/Mid-Atlantic Air-Source Heat Pump Strategies Report can help clarify things.

Indoor section of heat pump.

 

Outdoor section of a heat pump.

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