Summer is a great time to think about an energy retrofit

Insulation, air sealing, and modern heating and cooling equipment make for comfortable homes year round.

The fourth of July has come and gone and temperatures are steadily climbing here in Portland.  Fingers crossed we’re in for more of the same in the coming weeks.

The only downside to the recent nice summer weather is that it can make for hot homes. We’ve all walked up the stairs of an older home only to be greeted by an oppressive wall of hot air. This is a sign that your attic or roof insulation isn’t up to snuff and that your home could benefit from a home energy retrofit.

cathedralized attic

The key to keeping a house cool during the summer is building a good barrier between the outdoors and the home’s living spaces. This barrier also helps keep a house warm in the winter.

Good barriers or envelopes rely on adequate insulation and air sealing. The insulation keeps homes cool by slowing heat transfer, and the air sealing limits movement of air through that insulation, ensuring it can do its job.

In Portland’s relatively mild climate, just installing good insulation and air sealing is often sufficient to make a home comfortable during the summer. Coupled with a mini-split heat pump, these measures can transform even the most uncomfortable room – like that converted attic space or upstairs playroom – into an indoor oasis.


Mini-split heat pumps have two major components: a unit mounted on an inside wall that delivers cool air to a room and a unit mounted outside the house. A compressor and two refrigerant lines “move energy” to cool or heat a home.  They’re a great alternative to upgrading an entire HVAC system.

mini-split efficiency

photo from Daikin 


In the Pacific Northwest, mini-splits can reach 300 to 400 percent efficiency: or every unit of electricity consumed the heat pump generates 3-4 units of energy for heating and cooling. Our friends over at brute force collaborative compiled photos of some ductless mini-splits that look as good as they perform. Mini-splits can also be hidden away by tucking them into conditioned attic spaces.

Want to create a refuge from both summer heat and our wet, cold winters?  Consider buttoning up your home’s envelope and adding a mini-split heat pump system.

– Cody

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