Thermalstat! By Chantal Keerak
Part five of an ongoing eight-part series
When building, buying or renovating a home most people focus on the price, layout, size and aesthetics of the home. It can be easy to forget that there are other very important things that are not easily seen that need to be considered such as energy efficiency, thermal comfort, and adequate ventilation. If these factors aren’t considered in your decisions it will cost you year after year in higher utility bills and sacrificed comfort. The economics of investing in a home or renovation that is more energy efficient can often give returns that are better than almost any other financial investment.
When purchasing a new home, the past energy bills may not accurately reflect how much it is going to cost you to heat the home. What temperature did the past owners keep the home at? Were all the rooms kept at the same temperature? Were they away a lot? What percentage of the heating cost is related to hot water usage? Were the bills you are looking at for a colder or warmer than average winter? If the home has been renovated or updated don’t assume that the insulation was also updated. We were asked to assess a home in Revelstoke where the owners had just purchased an older home that been recently renovated with all new drywall. Their heating bills were over $600 a month, which was more than double the previous owner’s bills. We discovered that the home was completely uninsulated. When the renovation was done, they drywalled over the uninsulated plaster walls and ceilings and did not insulate anything. They also later found out that the previous homeowners only lived in the home a couple of days a month and the temperature was kept really low when they were away.
An EnerGuide rating is the best way to tell how energy efficient a home is. The government subsidizes the cost on existing homes so the cost to the homeowner is only $150. The EnerGuide rating is a standardized rating so that you can easily and accurately compare homes against each other. Most companies that do the ratings will also be able to provide an estimated annual heating cost of the home using a set internal temperature and average weather data. A report with the most economic ways to reduce the energy costs and information on available grants will also be provided. There is speculation that within the next couple of years an EnerGuide rating will be mandatory on all homes being sold in British Columbia.
When building a new home it is often difficult to decide on whether certain energy efficient upgrades are worth the additional cost. There are some questions that need to be asked. What is the cost? What are the associated energy savings? How easy would it be to upgrade this later? Are there additional benefits to the upgrade such as improved convenience, comfort or indoor air quality? Is this a proven technology? It is also important to understand how the different components of the home interrelate. For example if you spend additional money on improving the insulation levels in the home the energy costs will be lower, the comfort will be greater and the cost of the heating system may be less since you may be able to install a smaller system. You can also get an EnerGuide rating on new homes based on the architectural plans. The EnerGuide rating will take into consideration how the upgrades will interrelate with the other components in the home and it will accurately compare the energy savings associated with a variety of upgrades.
When building a new home, maximizing solar gains in the winter months is something that should be taken into consideration. Strategically orientating the home and placing the majority of the home’s windows on the south side of the home will maximize solar gains and provide free heating to the home. In the summer the sun is much higher in the sky and adequate overhangs or shading from deciduous trees can shield these windows from the summer sun.
The home’s size is something that also should be closely examined. Creative layouts and storage solutions can often let you get away with a smaller home without missing the extra space. A smaller home means less building cost, maintenance and energy consumption.
Grants are available for existing homes for energy efficiency upgrades. Details can be found at www.livesmartbc.ca. Currently there is also a $1,500 grant from BC Hydro for builders who build a home that has an EnerGuide rating of 80 or more.
Chantal Keerak is a professional mechanical engineer. Her Revelstoke based company, VerdaTech Energy Management and Consulting BC, provides heating and ventilation system design and energy efficiency assessments for residential and commercial buildings throughout B.C. She can be reached at 250 814-8719 or firstname.lastname@example.org.