Components of a Cool, Comfortable Home

A number of factors influence how cool your home feels, and you have alternatives to air conditioning. If you choose AC, consider more efficient options.

Sealing Air Leaks and Insulating

Two of the most effective actions you can take to reduce cooling costs include sealing air leaks and properly insulating your home. These upgrades are usually recommended before or around the same time as air conditioner installation to make the biggest difference in comfort and savings.

In almost every home, materials separate over time, or they were never built tightly in the first place. Around windows and doors, between attics and living spaces, around plumbing and ductwork and in many other places, these gaps let a lot of air flow between living space and the outside.

Caulking, spray foam, rigid foam and weatherstripping close up gaps, holes and cracks that you may not even notice. Caulking seals smaller cracks or gaps; spray foam fills larger gaps; rigid foam or packed cellulose insulation stop air flow from larger holes. Weatherstripping seals off doors, windows, and other movable openings. Your contractor or Enhabit Home Advisor can help you determine which approach is best.

Insulation slows the transfer of heat through walls, roofs, and floors. This helps keep the heat out during summer, and works well in winter for keeping heat in. Add insulation to attics, underneath floors and in walls. Install fiberglass insulation between ceiling joists and floor joists. Blow in cellulose to attics or into inaccessible wall cavities via small temporary holes in the interior drywall or plaster, or underneath exterior siding of the home.

Benefits of air sealing and insulation:

  • Lower utility bills—Reduces the amount of heating and air-conditioning you need.
  • Increased comfort—Rooms stay warmer in winter and cooler in summer. Reduced drafts.
  • Improved indoor air quality—Stops outdoor pollutants from entering the home. Cuts uncontrolled flow of air from crawlspaces and garages.
  • Increased structural durability and longevity— Reduces maintenance and makes your house last longer.
  • Pest control—Prevents rodents and pests from entering.
  • Noise control—Reduces traffic, neighborhood, aircraft and other ambient noise.
  • Home orientation and shading

If your home has full sun exposure all day, it’s going to heat up far faster than another home that’s shaded by large trees. If you’re home is exposed, consider plantings to the south and west that will eventually grow large enough to keep the home shaded. Deciduous trees could be a good choice because they let light in during winter. Close window coverings to keep out light and heat during the day (see Household Habits below).

Air conditioning system

Air conditioning can take the form of central AC, which cools the entire house, or room-sized units mounted in windows or on walls. The room sized units can be a good choice if you spend most of your time in only a few rooms, or if the house’s sun exposure and orientation overheat some rooms more than others. See “Types of air conditioners” on page 9 for more information on types of air conditioners.

Active ventilation

Active (powered) ventilation can help homes feel cooler while using far less energy than air conditioners.

Room fans can help rooms feel 3 to 4 degrees cooler. After sunset, you can place box fans in windows to pull warm air outside. Set ceiling fans to pull air upwards. If your thermostat allows it, set your furnace to “fan only” mode to circulate air throughout the house.

Another option requires permanent installation. A whole-house fan is a ceiling/attic-installed fan that pulls air from the house into the attic, and forces hot air out through the roof’s built-in vents. It’s best to run the fan in the evening, and windows must be open to allow cool outside air into the home. These units cost much less than central air conditioning, and use about a quarter of the energy. Whole house fans can be a drawback in winter, however, because they may let warm air into the attic through the vent. Some homeowners don’t like the noise they can make, although this can be reduced through careful system selection.

Household habits

A few good routine practices can keep you cooler in your home without having to change anything about the home itself. Often these are the lowest-cost options.

In the Northwest, evenings can be quite cool even during hot spells. One approach to home cooling is to keep windows open at night and close the windows and shades during the day to hold in the cooler air. This works best after the home has been well sealed and insulated, but even if you’ve not been able to make those upgrades, you can try this approach.

When it’s hot outdoors, minimize sources of additional heat indoors. As long as it’s cooler inside than out, keep windows and doors closed. Use few lights, or convert warmer burning bulbs like incandescents to cooler LEDs (Energy Saver Kits with bulbs and other products may be available to you at no charge. See Hang clothes on a line instead of running the dryer. Skip baking, eat cold food, or cook outside on a grill to keep interior cooking heat to a minimum.

If you can, sleep on the ground floor or in the basement instead of an upper story.

Is an air conditioner necessary in Oregon? The cost for a new air conditioner starts at about $3,000 and goes up depending on the size of your home and the type of system. You can make a good decision about home air conditioning by considering your climate, your home, and your family’s ability to cope with uncomfortable heat.

Are you comfortable?

It’s tempting to make decisions based on a few days of discomfort during a heat wave. Getting through these times can be a trial, and it may or may not warrant an expensive investment in home upgrades. Each household is unique.

Families with young children or elderly relatives may consider potential health impacts of the hottest days reason enough to install air conditioning.

Some families just don’t like feeling hot and may use air conditioning for weeks at a time. The answer will be different for every household.

Understand your home factors

Your home’s configuration, construction, energy efficiency and position relative to structures and trees can be big factors in summer comfort.

An un-insulated wood-frame house that receives full sun all day can really heat up, while a similar house with good insulation and large shady trees will stay noticeably cooler. Taking steps outlined on pages 3 and 4, like planting trees or insulating, can have a big impact.

Have you done everything to increase comfort without Air Conditioning?

After reading “Components of a cool, comfortable home” above, you might have some new ideas to try. If you’ve already tried everything but AC and need to make an upgrade, it might be time to take the next step. A contractor specializing in energy efficiency can help by evaluating your home and helping you make upgrades to increase comfort and efficiency. You can try this approach before investing in an air conditioning system.

Know your climate

Oregon temperatures are experiencing an overall trend toward hotter summers, with record-breaking heat in Oregon in 20151 and globally in 2016.2 Still, it’s wise to consider the climate as a whole instead of making home upgrade decisions based on a few uncomfortable days.

Generally, the closer you are to the coast, where the ocean moderates temperature, the milder your summer high temperatures. Eastern and southern parts of Oregon see consistently warmer weather in summer months. Most coastal dwellers can get by without air conditioning.

In much of western Oregon, including the Willamette Valley and the Portland metro area, relatively mild summer temperatures are sometimes interrupted by heat waves like the record-breaking 3-day span in August 2016.3

Portland experiences a heat island effect that makes it hotter than nearby areas. The concentration of buildings and streets increases city temperatures an average of 4.8 degrees higher than surrounding rural areas.4

If you live in one of the hotter regions like Jackson County, you’ll likely already have air conditioning or other ways to cope with extended hot weather. If you already have air conditioning, your best bet is to keep your system operating as efficiently as possible, and consider other energy saving measures for your home.

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1. January 08, 2016 “2015 was Oregon’s warmest year on record, data shows”
2. January 18, 2017 “2016 was the hottest year on record”
3. August 20, 2016 “Portland breaks heat records three days in a row”
4. report “Hot and Getting Hotter: Heat Islands Cooking U.S. Cities”