A while back I visited a very old home in a historic district in a Virginia town. The new owners were just finishing unpacking when I came to do an energy audit. I was very sad to see that they had purchased a new boiler and water heater before moving in. Both appliances were the least efficient models available for purchase these days.
Mostly the new owners wanted to talk with me about what to do about their windows in a neighborhood where the law prevented changing the historic façade. Of course the ancient single-pane windows are a huge problem – but there are no cheap or straightforward solutions. Meanwhile their brand new boiler and water heater were 80% efficient – that’s one in five of their gas bill dollars thrown away. The best new models are up to 98% efficient.
The problem here is a failure to think of the whole house as a system. Upgrading to high-performance equipment would have reduced energy costs just as much as spending a ton on custom interior storms or significant rebuilding of the historic windows – without any extra work or intrusion into their home.
So don’t get hung up on one problem in your home. Call an experienced energy auditor who will consider how all of the systems in the home are working. You may be surprised to learn where there are cost-effective ways to save energy. And do this before you buy the home! Or at least before you make major investments in it.
CSW Principal Andrew Grigsby will teach a class for energy auditors at the Culpeper, Va. campus of Germanna Community College starting October 15, 2012. The $1450 tuition includes written and field exams for the Building Performance Institute’s Building Analyst (BA) exams. Partial scholarships are available from the Virginia Weatherization Training Center.
This class is a thorough introduction to residential building science and to the diagnostic testing of houses. Topics covered include heat and moisture movement, air-sealing, insulation, home inspection techniques, HVAC, indoor air quality, appliances, combustion safety, utility bill analysis, and more. Classroom lectures and hands-on practice in houses are used to teach concepts and to familiarize students with the blower door and combustion analysis tools. The class prepares students for the Building Performance Institute’s Building Analyst (BA) exams. (Learn more at www.bpi.org.) The first week of training (40 hrs.) ends with the BA written exam Friday afternoon.
The second week (Oct. 22-26), each student will participate in three 4-hour small group mentoring sessions to master the diagnostic equipment and inspection strategies. On the third week (Oct. 29-31), students will take the 2-hour BA field exam. Specific mentoring session and field exam times will be scheduled individually on the first day class.
The big training firms charge a lot more money for half as many hours of training. This is superior training at a great price. See registration information on Germanna’s website. The class number is 32152.
This really could turn into something. At the urging of the Federal Office of Science and Technology Policy, utilities have begun developing a set of standards and procedures to make energy use data easily accessible to energy consumers. Once this standardized data stream is in place, supporters expect that companies and technologies will develop to use that data for consumer applications, targeted efficiency improvements, community energy programs, and more. It’s government initiating the collaboration to spur helpful innovation. See http://collaborate.nist.gov/twiki-sggrid/bin/view/SmartGrid/GreenButtonInitiative.
The average US home is said to have greater than 15% duct leakage to the outside. That’s money going right out window. Sometimes there are cheap fixes. The fix pictured below cut more than 50 CFM (that’s cubic feet per minute) of leakage from a new home. We removed the grille from the HVAC supply register and sealed the metal boot to the surrounding drywall – for just 4 registers. We used mastic. Painters’ caulk works fine too. The grille will cover the grey mastic.
The chart below shows the distribution of energy use in the average US home. Of course every home is different, but this may give you an idea of what changes will bring you the greatest savings. Source.