A building envelope consists of the walls, windows, foundation and roof and isolates the building’s climate from the exterior climate. The U.S. DOE claims that a building’s envelope accounts for “approximately 30% of the energy consumed in residential and commercial buildings and plays a key role in determining levels of comfort, natural lighting, ventilation, and how much energy is required to heat and cool a building.” Retrofitting a building’s envelope or designing a new building with the envelope in mind is essential to the building’s energy efficiency.  

Benefits

• Increases indoor comfort
• Reduces energy bills
• Reduces carbon emissions
• Increases productivity of building users
• Can be subsidized with government rebate programs.

Challenges

• Can decrease ventilation, increasing the risk of trapping harmful gasses within the building.
• Expensive upfront cost.