• In this video, This Old House general contractor Tom Silva explains how to replace a basement window.


    1 Remove the sash from existing basement window.
    2 Use reciprocating saw to cut through the window frame.
    3 Pull out the old window frame from wall opening.
    4 Use hammer and cold chisel to chip away mortar from sides of opening, if necessary.
    5 Slide new window into the opening.
    6 Use shims to center new window in the opening.
    7 Secure window by screwing up through its frame and into the mudsill.
    8 From outside, apply caulk along the sides and top of the window frame.
    9 Spray urethane foam under the sill to seal the bottom of the window.
    10 Apply a coat of exterior-grade primer to all bare wood window parts, followed by two paint topcoats.
    See products and services from this episode
    • Difficulty: Easy to moderate
      Difficulty increases when new window is larger than the opening
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      Video Directory

      Selected Topic/Section

      Tools List

      • hammer
      • 100-foot tape measure
        Tape measure
      • utility knife
        Utility knife
        used to trim shims
      • cold chisel
        Cold chisel
        used to chip away old mortar from window opening
      • chisel
        Caulking gun
      • caulk gun
        Whisk broom
        used to sweep away debris
      • push broom
        used to drive screws
      • drill
        Reciprocating saw

      Shopping List

      1. Basement window

      2. Butyl caulk

      used to seal around window

      3. Expandable urethane foam

      used to seal under window

      4. Wood shims

      used to hold window centered in opening

      5. 2 ½-inch decking screws

      used to fasten window

      6. Exterior-grade primer and paint