How to Measure Window Sills

The sill of the window is simply the bottom of the window frame. A window sill can exist in one of four states: finished drywall, unfinished with the window framing studs exposed, finished using a nice window sill material or finished with old, deteriorating window sill finishing material. A new window sill is very easy to install, but before installing a window sill, the sill area has to be measured so the window sill material can be sized to fit the area correctly.

Things You'll Need

• Shop vac or vacuum
• Tape measure

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Instructions

1. • 1

     Remove the old window sill material and all associated debris from the window sill area, if required. Use a vacuum or a shop vac to be sure all small bits of debris are removed.

   • 2

     Stretch a tape measure from the window frame to the edge of the wall to find the depth of the window sill.

   • 3

     Stretch a tape measure from one side of the window opening to the other to measure the length of the window sill.