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In Part 1 of this two-part series, we started to explore what is involved in a Comprehensive Home Energy Audit. In Part 2, we are going to discuss other home audit types to understand better why homeowners who are truly interested in knowing more about their home should choose a Comprehensive Home Performance Assessment instead.
So if you are on this site, reading this blog, there is a very good chance that you are a homeowner who is interested in pursuing a home energy audit in the Chicagoland area. It’s late December; the weather outside is frightful, the drafts in your home… not so delightful. If Vitamin D deficiency weren’t enough to make you SAD, you now come home to an uncomfortable house, and to make it worse your utility bills and your checkbook are quite cross with one another. You gotta do something!
Well, thankfully you’ve found our blog and are hopefully amused/intrigued enough to continue reading. Through doing so, we hope to convince you that the services we offer are exactly what you are looking for in a home energy audit.
Yo u’re cold, your bills are high, and you’ve got window, furnace, and insulation companies each advertising savings of up to 30%. Who do you trust? This is a tough decision for many homeowners, many of whom don’t really know much about their home’s construction attributes. Truthfully, even handy, do-it-yourself oriented homeowners aren’t that familiar with some of the main culprits of home energy inefficiency; leaky band joists, unsealed top plates, non-IC rated recessed can lights, uninsulated bump-outs, and excessive temperature rise in your furnace. Eek… All of these relatively unknown features of your home could be part of your comfort and energy efficiency problems.
So we’ve established that your home is complicated, and although you know it has single-pane windows and could probably use some more insulation, you aren’t really sure where to invest your energy efficiency improvement dollars. You are probably a great candidate for an energy audit. However, beware of the Checklist Audit.
 The Dreaded Checklist Audit Most of you have probably heard of them. They are “home energy audits” that are offered for $99, $49, or even FREE by organizations such as utilities, municipalities, and even contracting firms such as window, heating/air, and insulation companies. During these audits, organizations will show up to your home with a checklist, which the company will use to document issues relating to a short-list of home energy issues. They will probably count your light fixtures, take a short look at your heating/cooling systems, and might even check to see if your faucets have aerators. In the end, they will use an undisclosed rubric for scoring your home’s checklist, and at that point, they will give you a list of improvements to consider. If it is a utility or municipality, it will probably be related to a short, vague list of issues, most of which will have nothing to do with how your home performs as a system. If it is a contracting firm they will likely … surprise surprise… recommend that you purchase whatever contracting service they offer. Remember, although it is quite possible your windows or insulation are not as good as they could be, are you really positive that they should be your highest priority investment? Without a doubt, that contracting firm certainly thinks so. With this in mind, I think that you’ll agree that the old adage… “you get what you pay for” certainly rings true. So who can you trust?
If you’ve read Part 1 of this series, you should know that at Green Dream Group, we perform a style of energy auditing called a Comprehensive Home Performance Assessment. Through this process, our auditors evaluate your entire home – including the more obscure areas listed above. During our audit process, which follows the national standards for conducting home energy audits as established by both BPI and RESNET, we uncover opportunities for improving the comfort, energy efficiency, durability and safety of your home. We then generate prioritized recommendations to show you exactly which improvements should take precedence, and model your home in energy modeling software to show you the simple payback of each recommended measure. We’ll also show you the estimated payback on other measures that we typically do not recommend to most homeowners due to their excessive cost (new windows typically have a simple payback of 50-250 years!).
The best part is that Green Dream Group is not a contracting organization, and therefore have no vested interest in selling you on any particular product or improvement service. We do have a list of approved Affiliates, many of which we have trained and can attest to the quality of their work. However, we never accept financial kickbacks from these organizations, but instead ask them give our clients a discount on their work. If you do choose to get work done after we’ve given you our report, we offer a free return audit to make sure that the improvements that were made were done correctly and that you will be completely comfortable, safe and satisfied afterward.
So there you have it. The difference between many other home energy audits and Green Dream Group’s Comprehensive Home Performance Assessment is quite significant. If you are truly interested in getting a better understanding of how your home works, so that you will be more comfortable during extreme weather, have lower utility costs, and have the piece of mind that your home is safe and solid, give us a call and we’ll be more than happy to help.
Green Dream Group strives to be active in promoting building performance and energy efficiency within the Chicagoland community. Within the past month, we have been exhibitors/presenters for 5 different events/groups relating to building performance and sustainability in and around Chicago – the Evantson Green Living Festival, the Peggy Notebaert Nature Museum, the National Association of Realtors, Chicago Green Homes, and the Illinois Chapter of the United States Green Building Council (USGBC).
 Green Dream Group is a proud member of the Illinois Association of Energy Raters and Home Performance Professionals Through many of our discussions with homeowners at these events, we have found that there is a general misperception of the services that our company and others like us in the Illinois Association of Energy Raters and Home Performance Professionals provide. That misperception stems greatly from the term Home Energy Audit.
“Oh, you guys do home energy audits. I had one of those a few years ago,” is a frequent comment that we hear. When we ask how it went – whether it helped them lower their utility bills, increased their comfort within the home, and enhanced the indoor air quality of their home – most people do not respond in an affirmative manner.
It is difficult to say exactly why each of these people experienced rather underwhelming results from their home energy audit. However, in our experience most people who complain of poor results from a home energy audit do so because their expectations of increased energy efficiency, comfort, and improved indoor air quality were not met. This unfortunate circumstance is a result of a home energy audit being conducted in a narrow, unfocused fashion that does not align with national standards for conducting audits. What they got was something called a home energy audit, but what they needed was a Home Performance Assessment.
In Part 1 of this 2 part series, we are going to explore exactly what is a Home Performance Assessment. In Part 2, we will investigate how a Home Performance Assessment compares to other home energy audit methods.
Home Performance Assessment
The term Home Performance Assessment describes a whole-house approach to diagnosing the safety, comfort, energy efficiency, and durability of a building. The term “whole-house approach” can be a bit confusing for some people, so let’s try to unpack it a bit.
 Green Dream Group is certified by the Building Performance Institute to conduct Home Performance Assessments The conventional way to view a home is to look at it like a cluster of objects that are acting independently of one another; inside a home you have a basement, a shower, an attic, a furnace, and so on. This view implies that these many different objects operate independently of one another, whereas in reality, similar to the human body, all of these parts are not independent but rather function as part of a greater system.
Most homeowners would never conceive that leaks in an attic could cause cold air to infiltrate into the home through the basement, causing the furnace to run longer to maintain a comfortable temperature, and that this same cold air could cause mold to form by mixing with the hot, humid air from the shower. However, it is precisely these complex interactions between seemingly unrelated parts of the house that can cause homeowners to be uncomfortable in their home, have high energy bills, and experience health problems associated with poor indoor air quality.
Thus, through utilizing a systematic, whole-house approach to diagnosing a home, the Home Performance Assessment strives to uncover how the house performs as a system, and how it can be improved to function more optimally. To do so, Green Dream Group performs scientifically-based tests using a variety of diagnostic testing equipment to quantify exactly how the home is performing.
Through this process, we are able to pinpoint problem areas, such as ceilings or walls with missing insulation and zones of the home that leak excessive amounts of heated/cooled air. In addition to analyzing the home for its energy performance, we survey the home for any durability issues and conduct combustion safety testing on gas-fired appliances to ensure that the home is safe, durable, and healthy for its occupants. Because we utilize the whole-house approach to addressing a homeowner’s concerns, we are able to recommend opportunities for improvement that will resolve the homeowner’s original concerns, while improving the safety and durability of their home at the same time.
So there you have it – Home Performance Assessments are a crucial first step to improving your home. If you think that our whole-house approach sounds like it would work for your home, click here to book with us today. But what about that free “home energy audit” that your utility or local insulation company is offering? Won’t that be just as good? Part 2 of our series, we will discuss the difference between a Home Performance Assessment and other home energy audit methods. Stay tuned…
A new era has begun!! I just passed my BPI written exam (field test and official certification coming soon, I hope).
The class was excellent.* Really excellent. Not only was an enormous amount of knowledge expressed – and mostly absorbed! - over the course of 6 days, but the clarity of thought you need to accurately apply that knowledge to the bizarre situations that happen all too often in buildings was somehow passed from Corbett to the rest of us taking the class. Granted, I’ve never tried learning building science from someone else. But I suspect that Corbett’s clear presentation style and mastery of the the topics he teaches would be hard to match, let alone beat.
And he doesn’t let knowledge stand in the way of understanding. Our field “training audits” were an excellent counterpoint to the classroom presentations, and even though I’ve been doing exactly this kind of audit for over a year with him, it felt entirely different to be in the driver’s seat during that process. Balancing the time it takes to do a focused inspection with combustion safety testing and a solid blower door test… it takes great presence of mind, not to mention a head for the details that make or break a safe testing situation. Like, for example, remembering to turn combustion appliances to pilot before running the blower door. Simple thing. Enormous safety ramifications if forgotten. (And now that I’ve mentioned it here, if I don’t remember to pilot appliances on the written exam, I’ll kick myself!)
I have to say, I thought I would feel more mastery of building science after passing this exam than I do right now. But it’s probably for the best. I wouldn’t want to get sloppy, thinking that with this one certification the learning process is over! After all, there are building science certifications, conferences, books, research, and experiments being advanced all the time, all over the world. So I don’t expect that these blog entries will change much, since I’m still finding my way in the expansive world of the building performance professional. I’ll still share the little things I discover with you, and try to keep the language as clear & comprehensible as possible.
So I’m looking forward to the new era, but I guess it won’t be all that different from the old one. Here’s to life, and the constant process of learning that makes it awesome!
*I should also mention that I don’t actually work for Green Dream Group any more, other than writing the occasional blog entry, so I’m not being pressured to say that the class rocked!! In fact, while working for Green Dream, I wasn’t able to take the field exam with Corbett, thanks to the conflict of interest he had with me as an employee that he wanted to see certified. In case you’re curious, I now work at CNT Energy, as part of their “Energy Savers” team, where the focus is mostly on reducing utility bills for multifamily buildings. So drop me a line if you own one: llittle at cntenergy dot org. Looking forward!
Some of the home killers we’ve discussed target your wallet, some target your building. This final home killer makes it seriously personal. It targets you – and your family.
Home Killer IV is: Indoor Air Quality (IAQ).
Surprised? Don’t be. Statistics from the EPA indicate that most Americans spend over 90% of their time indoors, breathing air flavored by whatever the building is full of. And most of those flavors aren’t exactly good for you. The LEED (Leadership in Energy and Environmental Design) rating system gives points to homes and commercial buildings that use materials known to off-gas smaller amounts of volatile organic compounds, or VOCs. But, even though some may be carcinogenic, VOCs aren’t anywhere near the worst of it. The U.S. EPA website has a more complete list of sources of poor indoor air quality, including radon, tobacco smoke, mold & moisture, and carbon monoxide: http://www.epa.gov/iaq/index.html
Carbon monoxide is the one IAQ threat that’s most central to the national standards energy auditors use, and it’s also responsible for several hundred American deaths each year. You probably know that carbon monoxide is produced from incomplete combustion of fuels, including natural gas. It follows that the places to watch out for high levels of CO are near the oven, furnace, boiler, and water heater, or in your garage (especially attached garages). Because it’s produced along with heat, CO tends to rise at first, but over time it will mix with the air in a room fairly uniformly. Standards vary on what a safe level of exposure to carbon monoxide is. BPI (the Building Performance Institute) allows exhaust concentrations of CO to reach 35 ppm before recommending repair to the appliance being tested.
Normally, any carbon monoxide produced by combustion-powered appliances is vented directly to outside, so it’s absolutely no problem inside a house. Problems only arise when something is wrong, which we see far too often for comfort. Simple things, like closing off the leaky vent above an old oven, can elevate indoor CO levels in a home far above what’s considered safe, even if it seems to be a good idea and makes your kitchen warmer. Running a ventless gas heater or fireplace indoors is never a good idea; remember that ‘ventless’ means you’re breathing the byproducts of that combustion! And there are many more complicated ways for combustion to go wrong, though I won’t get too far into them here.
One of the places dangerous mistakes are made is in the area around your combustion appliances, creatively named the “Combustion Appliance Zone”, or CAZ. Newer appliances may be power-vented, or have a draft inducer which effectively forces them to properly vent gases to outside. But many more appliances depend on an adequate air supply to work the way they were designed to. If you have both a furnace and a water heater together in a small, enclosed CAZ with only a few vents, take a second to imagine what could happen when both machines are running. The furnace is a powerful beast, pulling air to itself with a fan, making sure it combusts efficiently. But the water heater isn’t as strong. It tries to pull air in, it tries to put its fumes out the right pipe, but if there’s not enough air in the CAZ to go around, the furnace may end up sucking combustion gases back down the water heater’s exhaust flue to feed itself. That doesn’t bode well for anyone. It’s still possible, even under those conditions, that there won’t be dangerous levels of carbon monoxide in your house – the water heater might only be producing a few ppm. But that doesn’t mean it will always be safe, and where your family’s concerned, safe is the only acceptable solution.
Thus ends the exciting Home Killers series! Post a comment, ask a question, leave a story, argue a point – make sure you understand how these home killers will try to get to you, so they never get that chance.
Home Killer III: Airflow (alias: Pressure)
 Like heatflow & airflow... Home Killer II (Heatflow) and Home Killer III (Airflow) are best pals: they work intimately on all kinds of fronts. Heatflow is one of the factors that determines the direction of air movement, along with wind outside, or the air movement induced by forced-air heating systems. Airflow isn’t slowed by fiberglass insulation like heatflow is; it can only be stopped by an “air barrier” like dense-pack cellulose or closed cell sprayfoam. Confusing airflow and heat barriers leads to confused houses, which kills your wallet faster than anything else, both in utility bills and in the costs of construction.
 Conditioned Space or Not? Ideally, the pressure and heat boundaries should be in the same place in your house. Your house gets confused when that isn’t the case, the same way you’d get confused if you realized you had three arms, but couldn’t feel one of them. Examples of places where heat & pressure boundaries get confused: garages, crawl spaces, partially conditioned areas, and the areas around vaulted ceilings. I saw one house recently where workers had used more than twice as many materials as they needed to insulate the short side attics below the vaulted ceilings. Not only was that space insulated at the roof and the exterior wall, which by itself would have achieved the same results; there was also insulation against the interior wall, the floor, and the access hatch. Ask yourself this: If there was insulation and air-sealing at the roof, what was all that extra stuff on the interior walls and access hatch insulating against?
 Where Air Escapes Let’s take another look at how airflow and heatflow work together. The last entry explained what stack effect is: here’s another piece of how it works. Average houses in the Midwest can have anywhere from 2 to 5 square feet of what amounts to holes in their envelope, spread out in the form of cracks, gaps, and joints across their entire surface. Gaps located in the upper area of the house, where buoyant warm air wants to go, let already-heated air slip right out into the world. The gaps in the lower reaches of the house allow cold air from outside to seep in to replace the air that’s escaping up above.
 Somewhere in your house, there’s a level where the air inside isn’t trying to get out, and the air outside isn’t trying to get in – where pressures are equal inside and outside - creatively named the neutral pressure plane. That’s actually one of the reasons it’s so important to use a blower door when testing for air leakage in homes. Because pressure relationships dictate that air seeps in where the pressure is lowest (code for the basement or lowest floor) an infrared scan without a blower door would show lots of leakage from outside in a basement, and no leakage at all on the upper floors. Believing that infrared scan would be a huge mistake; it would result in advice that’s the opposite of what we usually give. Sealing and insulating the holes in your upper floors, where air’s always trying to escape, is the best way to slow down stack effect, thereby slowing down the rate at which you pour money into your utility bills.
Stay tuned next week for the final installment of Home Killers. Next time, it’s personal!
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