Baseboard & Trim Calculator (Linear Feet)
Calculate baseboard or crown molding linear feet from room perimeter, minus openings.
What this calculates
Trim is sold by the linear foot in standard lengths (8, 12, 16 ft). To buy the right amount, calculate room perimeter, subtract doorways, and add waste for miter cuts. This calculator handles both baseboard and crown molding.
Formula & how it works
Perimeter = 2 × (length + width). Subtract sum of door widths. Add waste % (10-15% typical) for miters and mistakes. Pieces = ceil(linear_ft / stock_length).
Worked example
12 × 14 room, two 3 ft doors, 12 ft stock, 12% waste. Perimeter 52 ft − 6 ft = 46 ft × 1.12 = 51.5 ft → 5 pieces of 12 ft stock.
Frequently asked questions
Why more waste for trim?
Miter cuts at corners produce waste triangles. Inside corners are easier than outside; crown is wastier than baseboard.
Match grain/run?
Buy 10-20% extra of the same lot for stain match. Hardwood trim varies bath-to-batch.
Cope vs miter?
Coped inside corners hide gaps better than mitered. Miters are faster but less forgiving on out-of-square walls.
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