How to Gauge the Energy Efficiency of a Prospective Home

how to find an energy efficient home

Years ago, my parents bought a home that was 20 percent smaller than the one before it. That’s why Dad was shocked when the first full month’s light bill arrived. It was about 50 percent more expensive than the bill for the previous home! The increase was to the tune of about $1800 per year … and they ended up owning that house for 20 years! Do the math.

Sometimes key areas of inefficiency aren’t mentioned on home inspection reports. But you really should care, as energy bills can turn into “gotcha” items down the road.

When you’re evaluating homes, you may not think to ask about energy consumption. Lenders and insurance companies don’t care about efficiency very much, so sometimes key areas of inefficiency aren’t mentioned on inspection reports. But you really should care, as energy bills can turn into “gotcha” items down the road.

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To get to the bottom of a home’s energy efficiency, ask these five questions when you’re out house hunting. Maybe they’ll help you avoid a $36,000 unbudgeted cost!

How New are the Major Systems?

Some of the largest energy consumers in a typical home include:

  • Electric heat and air-conditioning
  • Gas heat
  • Hot water heaters
  • Swimming pool heaters
  • Water pumps
  • Major appliances (oven and dryer mostly)

An older system that is nearing the end of its life cycle will usually use substantially more power than a brand new system. Be sure to ask about the age of a home’s major systems.

Age isn’t the only factor that can affect performance. For example, you might be looking at a two-story home that only has one HVAC system to serve both floors. Even though the home inspection reports that the system is in good shape, the ductwork could be designed in such a way as to restrict airflow and cause inefficiency while also making it really difficult to keep the whole house at an even temperature. A professional in the trade would be able to inspect the system and report back on any issues. An inspection like that would usually have a cost associated with it, so the first step might be to just ask the seller, "Does the house stay evenly cool?" or "How are the energy bills for this house?" If answers seem to indicate a potential problem, it could be worth the additional money for a professional evaluation.

How Efficient are the Windows?

If you’re shopping for homes in an area that experiences hot summers and/or cold winters, the quality of the windows in a home can be worth thousands of real dollars in ownership costs.

Are the windows high quality? Single, double or triple glazed (more is better)? Do they seal up well, free of gaps that could create drafts? If double glazed or more, is the cavity between the glass gas-filled? Gas filling can greatly increase efficiency (but don’t be surprised if the seller doesn’t know the answer to this question).

How Well is This Home Insulated?

Sometimes your home inspector will be able to give you some feedback on the thickness and type of insulation in the attic and walls, but some homes are constructed in such a way as to make access to insulation impossible.

Generally speaking, homes of the same age and type will have the same type of insulation. If a home’s insulation has been upgraded, that detail may be the deciding factor when choosing between two or more potential homes of the same age in the same neighborhood.

What is the Glass-to-Floor Area?

Who doesn’t love a good sunroom or solarium, right? Just keep in mind that homes with lots of glass area are going to be much more difficult and expensive to heat and cool. If you’re looking at a home like this, the question as to types of window glass really becomes more important.

You don’t really have to do the actual glass-to-floor ratio calculation if that seems excessive to you. Just know that if you walk into a room and think, “Wow, lots of glass!” that room is going to be an efficiency buster. Of course, if you’re like me, and you love rooms with an abundance of glass, you probably won’t care and you’ll probably always say you bought the house because of that room!

Are There Exposure Issues?

Sun exposure depends quite a bit on where you are, but in general the southern to southwestern side of the house will get the most sun. So, a house on a hill, with no shade trees and no surrounding buildings, with a wall of glass facing in the sunniest direction, may have a bear of a time staying cool in the summer. Wind from open fields is another type of exposure that can make heating difficult in winter.

On the flip side, a house that enjoys some shade from neighborhood trees is easier to keep cool in the summer.

While It May Not Seem Sexy, This is Smart House Hunting

I know energy efficiency isn’t the most romantic of reasons to love or not love a house. But when you’re looking to make a purchase, chances are you’ll be looking at more than one home. Taking a few minutes to consider the energy cost while you’re shopping might really become a big part of your decision-making process when it comes time to pick your new home!

Happy house hunting!