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Window Sill Installation Instructions

How To Install Window Sills

The length and depth of the window sill must be specified by the client. The max length of a window sill is 120″, and the depth is typically between 4″ and 10″. If a window sill needs to be longer than 120″, it will have a seam and be sent in two parts.

Thickness is typically between 9/16″ and 5/8″. Finished edge(s) will have a slight radius, and the window sill ends will have straight, cut edges. When ordering, you must specify which ends are needed to be finished.

Window Sill Installation Instructions

  1. Clean ledge to your personal preference.
  2. Measure length of ledge.
  3. Measure length of window sill and trim window sill if necessary. If a trim is needed, we recommend cutting the window sill with a masonry blade on a skill saw; it can be dry cut.
  4. Place window sill on ledge to verify fit and look, pull window sill out.
  5. Lay line of adhesive material on ledge.
  6. Place window sill on ledge.
  7. Caulk around edges. Remove excess caulking.
  8. Clean window sill with warm, soapy water, or other cleaning product if preferred.

NOTE: Dark colored window sills will need to be polished to maintain luster.