What is Passive Heating and Cooling?
Last week, we published a blog on how to landscape your home for energy savings. In the same spirit of Earth friendliness and home comfort, we’re sharing some of the best passive heating and cooling tips for an energy-efficient house.
What is passive heating and cooling?
While homes today are a lot more energy efficient than the homes of yesterday, there are still many energy-saving opportunities that you may not be aware of.
Passive (non-mechanical) heating and cooling, as opposed to active (mechanical) heating and cooling, is basically the strategic use of things like sun, shade, orientation, ventilation, and insulation to heat and cool the home.
Passive heating and cooling not only lowers monthly energy costs, it also adds some very valuable amenities to the property, including beauty, style, comfort, and curb appeal. Sunny interiors, lush landscape, and lots of windows are popular with homebuyers.
Before you think about replacing your heating and/or cooling system, it’s highly recommended that you make some passive heating and cooling improvements to the home first.
Ventilation is the V in HVAC. You may not think of it much, but your home needs adequate ventilation for indoor air quality, energy efficiency, and comfort reasons.
If your home is too tight, you may want to speak with your HVAC professional about a fresh air ventilation system. Additionally, you should consult with an HVAC professional before you make any drastic improvements to insulation levels. While insulation is another passive heating and cooling technique, it’s easier than ever to create a too-tight home.
Some ventilation improvements will involve new design or construction, while others you can implement on your own. Natural ventilation refers to the ways you can use the air and breezes around your home to create a “chimney effect” (AKA the “stack effect”) and keep your home cool. If the air openings are unintentional, however, that’s called an air infiltration, which you should try to seal (learn air sealing strategies).
When air gets pulled in from the windows on your first floor, the air absorbs heat in your home and then rises and exits through upstairs windows. The “chimney effect” works best when your home has an open-air design.
Here are a few ways you can improve the natural ventilation in your home:
- Open up a window or door is the simplest and easiest way to introduce some needed ventilation into the home. The air and wind will naturally ventilate your home. Open up a window or door for at least 5-10 minutes every day.
- Speak with a professional about improving natural ventilation with windows, skylights, and rooftop vents on the upper floors. Also, consider solar fans to push hot air out of your attic, especially important if you have your HVAC system in the attic.
- You can also enhance your ventilation with landscaping strategies. Lots of plants and trees will reduce the temperature around your home and block cold winter winds at the same time. You can use landscaping to help force or block air to certain windows. Learn landscaping strategies to encourage passive heating and cooling in your home.
- The night purge ventilation strategy involves keeping windows and doors closed during the daytime and opening them up at night to push warm air out of your home.
- Natural ventilation works best in climates with cool nights and regular breezes.
Without proper ventilation, you could risk have indoor contaminants cause a health problem for the building’s inhabitants. Speak with the professionals at Pacific Heating & Cooling for more information on passive ventilation techniques.
Your windows are the number one source of heat gain for your house. You can create shade with trees, awnings, blinds, overhangs, louvers, and solar window film.
Improve your home’s passive heating and cooling by strategically adding trees and plants around the home.
Bodies of water near your home, such as pools, lakes, and ponds can help cool the air before it reaches the home. Strategically planned water features can also create cooling convective breezes.
Air Leaks and Insulation
Adding insulation to walls, floors, ceilings. roof and foundation improves their thermal resistance (or R-value). The R-value number refer to its resistance to heat flowing out of the house.
Improving insulation is a great way to save on heating and cooling costs and you may even get a rebate from your utility provider. Just be careful about adding too much insulation since an overly tight home can create breeding grounds for contaminants and put your indoor air quality at risk.
Passive Heating & Cooling Strategies to Consider:
- Lighten the color of your home and roof
- Install a radiant barriers and reflective insulation systems in your attic
- Caulk and insulate around doors and windows
- Add weatherstripping around all windows and doors to the outdoors
- Consider reflective coatings and solar screens for your windows
- Find and seal air leaks around the home, including around where utilities enter the building (HVAC, plumbing, electrical, etc.)
- Add trees and plants around the home
- Install thermal curtains, interior drapes and shades
- Add exterior shading, such as awnings, shutters, louvers, overhangs, vertical fins, and natural shade.
- Ventilate your attic, bathroom, and kitchen
- Increase natural ventilation
- Consider replacing inefficient, heat-generating appliances with energy-efficient ones
- Replace heat-generating incandescent light bulbs with more efficient LEDs or fluorescents.
- Caulk and seal air leaks under headers and sills
- Add attic insulation
- Seal your ductwork leaks (if you DIY it, use mastic sealant instead of duct tape)
- Test air leaks around your fireplace and install dampers and/or glass doors if you don’t have them already
- Install backdraft dampers on exhaust fan openings
Retrofits and renovations can get expensive. While redesigning your home with passive solar strategies in mind will certainly improve your building’s efficiency, it’s more complicated than swapping out one thing for another.
Discuss building efficiency strategies with your HVAC technician before you start planning expensive and potentially unnecessary building designs.
If you are thinking about replacing your heating and/or cooling system, keep in mind system efficiency.
Heating system efficiency is rated by the annual fuel utilization efficiency (AFUE). Cooling system efficiency is rated by the seasonal efficiency is rating (SEER). The higher the number, the better the performance. Learn what to know before buying a new HVAC system.
For more tips on landscaping for energy efficiency and other ways to reduce heating and cooling costs, contact the experts at Pacific Heating & Cooling.
You can reach us 24/7/365 at (253) 292-3995.
Since 1984, we’ve been proudly serving our communities in Federal Way, Graham, Spanaway, University Place, Steilacoom, Sumner, Lakewood, Puyallup, Tacoma and Gig Harbor.