Heating and Cooling System


Your home's centralized heating and cooling system uses lots of energy. Consider making it more efficient with a Smart Thermostat and duct upgrades. Ducts distribute the heated and cooled air throughout your house. Typically, 20-30% of the air the moves through the ducts is lost due to leaks and holes. Note that you might not have ducts in your home if you don't have air conditioning or use a wall heater. 


  • Save money: Sealed and insulated ducts will ensure that all the heated and/or cooled air reaches spaces in your home instead of leaked out of ducts. Energy efficiency measures could help you save 20-40% on your cooling costs.
  • Comfort: A well functioning air-conditioning system gives you precise temperature control and a more efficient system will allow you to stay comfortable in your home. 

Where to begin:

  • Purchase a Smart Thermostat: A Smart Thermostat allows you to control your heating and cooling system from your phone, create a heating and cooling schedule and more via an easy to use interface. Alameda Municipal Power offers discounted Smart Thermostats through their Marketplace. Click here to learn more. 
  • Seal your ducts.
    • Before you insulate your ducts, you must seal them. To seal your ducts, first inspect them and look for major holes or rust. If the damage is too bad, consider installing new ducts.
    • After inspecting the ducts, turn on your cooling system to detect leaks. You can do this with a smoke pen or a stick of incense. 
    • Mark the areas that need to be sealed.
    • Seal all leaks, joints, and seams with mastic sealant. Do not use duct tape, as it will not last. 
  • Insulate your ducts.
    • Once your ducts are sealed it is time to insulate them. Consider hiring someone to install the insulation. However, if you choose to do it yourself. Follow the steps below.
      • First choose your insulation. The insulation for your system must be rated R-6 and be heat resistant. 
      • Using a box knife, cut the insulation to the proper size and foil tape it around your ducts. Wear safety goggles to avoid getting fiberglass in your eyes.
      • Wrap the insulation snugly around the duct and use foil tape to secure the ends. Make sure to also foil tape the seams. 
      • Repeat until all the ducts are covered, and so that the seams and the joints of insulation are secure.
    • Purchase new ducts.
      • If your ducts are old, consider replacing them. You will need to hire a contractor for this step. Consider a BayREN approved contractor so that you can take advantage of Bay REN's rebates. Click here for more information.