Examples of Where to Insulate

• In unfinished attic spaces, insulate between and over the floor joists to seal off living spaces below. ^*
  • 1A - Attic access door
• In finished attic rooms with or without dormer, insulate:
  • 2A - Between the studs of "knee" walls;
  • 2B - Between the studs and rafters of exterior walls and roof;
  • 2C - Ceilings with cold spaces above;
  • 2D - Extend insulation into joist space to reduce air flows.
• All exterior walls, including:
  • 3A - Walls between living spaces and unheated garages, shed roofs, or storage areas;
  • 3B - Foundation walls above ground level;
  • 3C -Foundation walls in heated basements, full wall either interior or exterior.
• Floors above cold spaces, such as vented craw spaces and unheated garages. Also insulate:
  • 4A - Any portion of the floor in a room that is cantilevered beyond the exterior wall below;
  • 4B - Slab floors built directly on the ground; ^**
  • 4C - As an alternative to floor insulation, foundation walls of unvented crawl spaces;
  • 4D - Extend insulation into joist space to reduce air flows.
• Band joists.
• Replacement or storm windows, and caulk and seal around all windows and doors.

*Well-insulated attics, crawl spaces, storage areas, and other enclosed cavities should be ventilated to prevent excess moisture build-up.

**For new construction, slab on grade insulation should be installed to the extent required by building codes, or greater.

Courtesy of the DOE