How Tom Dasilva puts up crown molding

Russell Bateman
1 November 2003

Tom Dasilva of This Old House fame uses the following concepts to install crown molding. This is not Tom pictured here, but good illustrations I ripped off from another web site. See this excellent article at

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  • Use a C-clamp to fasten a ledger board to the the chop saw across the front in such a way as to keep the molding from slipping. Consider the horizontal base of the saw to be the ceiling during cutting. This is tantamount to cutting the molding "upside-down" in the saw.

  • Outside corners are always mitered. Using chop saw, cut molding in mock upside-down position at a 45° angle.

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  • To do runs, always start at left* cutting left end to fit previous structure as discussed below. Measure and cut to run the right end into the next corner (since the next piece after that will be coped).

  • Miter left-hand end and cope to the clean edge made by the miter saw. Cope steeply enough that the coped thickness will not prevent the edge from fitting tightly into the piece to which it is being joined. Coping like this, instead of attempting merely to miter, is what compensates for inexact angles. This sole technique will enable you to install crown at many different angles.

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  • To join molding in mid run (not at a corner or fitted joint), do not cut straight, but cut molding at 45° angle to its face and cut the next length at the complementary 45° to join.

  • Variation: Backing trim can be added a) to enhance the look of your crown molding and b) to more easily provide something to nail to:
  • * Or from the right depending on your political views or whether you are right- or left-handed.