Applied Building Science at CSG

July 01, 2010
July/August 2010
A version of this article appears in the July/August 2010 issue of Home Energy Magazine.
Click here to read more articles about Retrofit

Conservation Services Group (CSG) was launched in 1984 out of a small office in Boston’s Back Bay. Its mission was, and still is, very simple: to protect the environment and build a socially responsible clean-energy economy.

Mark Pignatelli, field manager at CSG, checks out a home's attic insulation. (Image credit: CSG)

In the early eighties, CSG employed a technique called nature’s thermal camera. This enabled CSG to identify the most inefficient homes quickly and accurately. After a winter snowstorm, technicians would walk around Boston neighborhoods and check all the rooftops for snow. If the roof was bare or had little snow, it meant the house was not insulated properly. Polaroid picture in hand, a CSG staffer would knock on the door and show the homeowner the bare rooftop. The homeowner would then get an education about weatherization. This was applied building science in its simplest form.

CSG has come a long way since those early days, but one thing has stayed the same—the firm’s unwavering commitment to applied building science. Currently, CSG runs dozens of programs coast to coast for utility clients, government agencies, businesses, and other groups. (For some humorous tips, see “Tips from CSG.”)

Applied Building Science Group

In 2000, the management at CSG decided to take its building science capabilities to a new level. Instead of being embedded in individual residential programs, a new business line, the Advanced Building Science (ABS) Division, was spun off. This new group was responsible for bringing applied building science to CSG as a whole, and to the wider community. With just two staff members, ABS initially focused on supporting CSG’s new-construction programs and clients, as well as the Residential Conservation Services (RCS) program in Massachusetts. (RCS was developed by the state to encourage energy efficiency and retrofits of existing homes.) The group also developed and delivered training to a wide variety of clients, including architects, builders, contractors, and others in residential design, construction, and systems maintenance.

Tips from CSG
  • Waterproof bronze sealer is hard to wash out of wool carpets. Take off your shoes after sealing a ground cover barrier. Especially if you are working in the home of an art museum director!
  • Don’t use the #16 foam tank as a stepping stool to foam around the bathroom fan—unless you are not afraid of slipping and knocking off the hose. If this happens, you’ll see the space between the sink and the floor fill up with sticky foam before you can say retrofit!
  • Make sure contractors are paying close attention when filling an attic cavity. It is easy to spray in too much insulation, burying the upstairs bedrooms in cellulose.
  • Don’t forget to clean the A/C condensate line after the contractor packs all the ducts.
  • Don’t blow out the ceiling on the day before New Year’s Eve. You might find yourself vacuuming a Christmas tree and buying the client a new sonic hologram generator, and other electronics that were ruined by static-charged dust.

New-Homes Program

In the late 1980s, CSG developed a new residential construction program called Energy-Crafted Homes for one of its first utility clients. (This predated the more widely known Energy Star Homes program.) This comprehensive building initiative comprised in-depth training, recruitment, technical plan evaluation and assistance, on-site performance testing, moisture control, and air quality standards. The program also included a marketing component to educate the public about residential energy efficiency.

Among the innovations that have emerged from this program, on-site testing of ground source heat pumps (GSHP) has been a key science-based approach. When CSG Technical Director Bruce Harley first encountered these in 1994, he set out to measure their energy efficiency. Since several clients were offering substantial incentives for GSHPs in new, energy-efficient homes, CSG wanted to ensure that its clients’ investment was being protected. After developing an on-site test to measure the whole system operation, Harley discovered that some systems consumed too much energy. (This discrepancy was usually due to oversized well pumps or other installation problems.)

In 2009, after learning that the current GSHP rating standard did not include most of the pumping or fan energy needed to actually run the equipment, Harley worked with RESNET to pass an amendment to the 2006 Mortgage Industry National Home Energy Rating Standards (or “RESNET standards”). This amendment, titled “Auxiliary Energy of Ground-Source Heat Pumps,” was designed to more accurately represent the real energy consumption of GSHPs in home energy ratings.

In 2010, CSG is collaborating with RESNET to clarify the treatment of conditioned and unconditioned basements and to improve and update some of the defaults used in HERS ratings to better represent the energy use of older homes. CSG is also working with a stakeholder group to bring empirically based cases to the software-testing process. In the new-homes arena, CSG promotes concepts such as optimum-value engineering, which reduces inefficient framing to allow for higher insulation levels. CSG also prioritizes investments in the building enclosure, which allows for downsizing and cost savings in heating and cooling systems.

“With every opportunity, we promote the good, science-based ideas and debunk the not-so-good ones,” says Harley. “It is important to protect raters, code officials, and consumers against baseless claims by the makers of radiant-foil or paint products, as well as monolithic products like structural insulated panels, insulating concrete forms, and [Autoclave Cellular Concrete] ACC.” He maintains that although this assurance is important during retrofits, it is even more essential for new construction.

Existing Homes

By 1990, CSG was beginning to roll out some of the first large-scale residential retrofit programs to incorporate blower door-guided diagnostics and air sealing in every home. Teams of CSG technicians would conduct an audit and seal up the house, monitoring leakage reductions and applying building ventilation standards and chimney backdraft tests to ensure that homes were not too tight. Air sealing, attic venting, and moisture mitigation were key components of all insulation retrofits. Within the year, CSG began incorporating duct sealing and heat pump diagnostics into these early audit programs.

CSG has followed thousands of homes through analysis of building design, construction inspections, and performance testing. To support this service, the firm has a number of tools for implementing and promoting its expertise in building science. One is a series of weatherization boot camps, for two of the firm’s largest utility clients. These sessions provide hands-on training and field examinations designed to ensure that contractors are prepared to use appropriate tools and techniques.

Part of the role of CSG's Advanced Building Science Division is to continually update company personnel on the latest building science. (Image credit: CSG)

By 2007, ABS had grown to 5 people. Today, ABS employs 13 people to keep up with CSG’s rapid national expansion. The ABS Division functions as a training resource; sets standards for installations, products, and quality assurance; develops savings calculations and energy modeling techniques; and engages with technical policymakers in the industry, such as BPI, RESNET, International Code Council, and DOE. The ABS team brings its expertise to clients by providing customized industry training and courses for architects, builders, general contractors, code officials, weatherization contractors, energy raters, auditors, and others in the trade. Training topics include HERS rater certification, green building seminars, air and moisture control, BPI certification training, and energy codes.

Within CSG, ABS has a role in evaluating new technologies. According to ABS Director David Weitz, many product claims are “sketchy” or “overblown,” making technical evaluation critical as the demand for energy-efficient equipment increases. ABS also works with clients who have varied approaches to calculating savings of new products or retrofit measures to ensure that the efficiency reporting is as up to date as possible.

Pignatelli checks out an instantaneous water heater in the basement of a home. (Image credit: CSG)

ABS also plays a critical role in CSG’s quality assurance operations. ABS supports all of CSG’s RESNET-accredited activities and is home to Mark Hutchins, CSG’s Home Energy Rating System quality assurance (QA) designee. According to CSG, it’s critical to keep the individuals implementing the QA process separate from the production environment, so that there’s no conflict.

The ABS Division supports a companywide technical committee, made up of quality service managers, directors, and other representatives from all six service regions across the country. The committee covers everything from combustion appliance testing to sprayed-urethane foam insulation. As issues are raised and resolved in the committee, technical bulletins are drafted to share the conclusions with CSG technical staff.

In the last few years, ABS has increasingly supported CSG’s many existing-homes programs. An increase in the demand for residential energy audits—in both cold and warm climates—has led to a new focus on retrofit work; 70% of the group’s work now comes from retrofit training and technical support for its retrofit programs. In recent years, ABS has taken on an increasingly central role in the development and deployment of the company’s software. According to Weitz, “It’s a natural evolution that ABS has become more engaged in CSG’s home audit tool. When ABS guides our retrofit programs, we can provide the best building science based on energy modeling and savings estimates.”

CSG launched an ABS technical library in 2008. This is an internally accessed database for the file sharing of documents, technical bulletins, Q&As, and other materials. The technical library has a chat function to cross-promote best practices among staff around the country. ABS is also launching an online help desk for technical questions. Like the findings of the technical committee, help desk resolutions are shared through the library.

Keeping It Simple

CSG’s approach to building science is simple: Make buildings the safest, most comfortable, and most energy efficient they can be at every level. For CSG, ABS is the essential ingredient in providing the best service to the industry and its clients. CSG will continue to raise the bar for technical performance, construction quality control, and responsible installations and innovations as the firm expands its services nationwide.

Lisa J. Rinkus is a public relations consultant based in Newton, Massachusetts. She has worked with CSG for more than 12 years.


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Find out more about CSG and the Advanced Building Science Division.

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