Your home’s walls play a role in letting heat escape during winter and allowing heat in during summer. If your home has ductwork that carries treated air, it should be air-sealed and insulated to maintain the desired temperature inside the ducts. 

To assess your walls and ductwork, as well as the rest of your home, you can schedule a complimentary Home Energy Assessment with Mass Save®. Their experts will offer energy-saving products for self-installation, suggest upgrades, and if necessary, arrange for weatherization professionals to seal and insulate your home. 

Though a standard home energy assessment doesn’t include a blower door test, it might be worth investing $300 to $600 for this test. It can reveal more ways to improve your home’s energy efficiency. 


Insulation is essential because it slows down heat movement through the walls, roof, and floors of your home. This helps minimize heat loss in the winter. When working with a professional contractor to enhance wall insulation, they’ll likely also air-seal any gaps prior to installing insulation.

A few changes that may be made:
  • If parts of your walls lack proper insulation, you can add more. Dense-pack cellulose is a common climate-friendly insulation type that’s blown into your walls. 
  • If your home has knee walls, insulating them prevents heat from leaking from your living space into the roof area. A home energy expert can add insulation between the studs of a knee wall and place rigid foam board insulation on the exterior-facing side.


If your home has centralized ducts outside the conditioned space (like in the attic, basement, etc.), sealing and insulating them enhances your HVAC system’s efficiency. About 20% of air moving through ducts is usually lost due to leaks and poorly constructed ducts. Mass Save’s weatherization professionals can seal and tape leaky ducts to decrease wasteful air loss. 

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