The naked eye cannot detect heat loss in a home. Photos courtesy of Michael Canavan
Michael Canavan
In today’s home environment, greater consideration is given to the energy usage of residential buildings – from multi-unit buildings to tiny houses. The adoption of higher performance energy codes is helping to improve energy usage in the new homes that are being built today. But what about your not-so-new house? How can you improve your energy usage with the older home you have?
We will discuss two levels of energy usage inspections and reports in this article series. Let’s start with a Home Energy Report. Elements of the report are property information, the building design, appliances and equipment, and optional observations.
For the property information section, the address and year the building was constructed, the number of residents and age grouping, and local energy type used and its costs are all basic required information.
With an infrared camera, we can see where the hot and cold spots are in the house on a warm day. The lighter areas show the hotter spots as in the attic and held in the basement concrete. Great way to see where the heat is escaping in the winter.
The building design sections of an inspection look at the building’s site orientation, height above ground, foundation type, and attic absorbency and type. Then the inspector goes for the details: insulation type and level, airtightness of the building, and window or glass opening area. This section gives the inspector the basic information on how the house is performing with the as-built conditions that exist.
Next, the inspector looks at the big energy users in the building: mechanical systems including the water heater and equipment for heating and cooling along with any connected thermostats; systems for distributing energy such as hot water piping, ductwork, and wiring; and appliances such as refrigerators, washers, dryers, and the overall lighting system with respect to the number of bulbs and the types of each one. Together, all of these indicate how much energy is being used and point to ways of saving energy.
Finally, the inspector is looking to fill in the optional information which includes items like common air leakage points, any moisture issues, green building features in the building and on the site. This section helps assess where the building is below standard and the components that are energy savers.
The information is entered into a computer program developed by the US EPA to produce a report. The report will determine the home’s carbon footprint, energy cost based on usage. It will evaluate the various systems equipment for age and efficiency. Then a list of upgrades for saving energy is presented as recommendations with the greatest payback listed highest, which helps the homeowner get the most return on their money earlier. The recommendations are usually within two groupings: the first is for upgrades for the building and the second is planning for the equipment and normally replaced items such as roof and water heater.
The second type of energy inspection goes much deeper into the workings of the home. The inspector will use additional equipment to understand the hidden deficiencies in the building. Heating and cooling energy in a building always wants to find equilibrium (hot goes to cool) which is thermal movement and high pressure fills in low pressure which is air movement. By using a blower door testing fan and an infrared camera (IR) more air leakage can be uncovered and be readily diagnosed.
The blower door test is a fan calibrated to move air out of the building at a target rate of 50 air changes per hour (ACH) as the minimum standard goal. When the home is depressurized to this rate the inspector can now go through the house and look for unwanted air leaking using a smoke pen and taking IR photos of suspect areas, gaps around attic insulation, window door openings, pipes, electrical outlets and so forth. This information is put in a much more detailed report that describes where leakage issues are uncovered, and recommended corrections for them, in addition to the basic equipment findings discussed earlier.
You, the homeowner, can begin to become more energy informed and educated by using the results of these reports to reduce your energy footprint and become a more efficient user of energy.
Michael Canavan is the owner of Eagle Home Inspection Solutions of Norwich Vermont. Learn more at EagleHomeInspectionSolutions.com or (802) 526-2642.
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