Trim Linear Footage and Miters
The trim to order for a room, and how many stock lengths that comes to.
Example
You enter
- Room perimeter (ft) 70
- Total door-opening width (ft, no trim below) 6
- Waste allowance (%) 10
- Trim stock length (ft, default 16) 16
You get
- Net (ft) 70.4
- Pieces 5
- Miter (deg) 45
Details, formula, and sources
Trim = (perimeter - door openings) x (1 + waste%), pieces = ceil(net/stock); corners are 45-deg miters (base/casing) or a crown compound cut. 70 ft perimeter, 6 ft openings, 10% waste, 16 ft stock -> 70.4 ft, 5 sticks; a 38-deg crown corner is ~31.6 miter / 33.9 bevel cut flat. Verify on a scrap.
net = (perimeter - openings) x (1 + waste%); pieces = ceil(net / stock); crown miter = atan(sin(spring) tan 45), bevel = asin(cos(spring) sin 45); else 45-deg miter.
Trim linear-footage takeoff and the crown-molding compound-cut angles, finish-carpentry practice, by name.
The linear-footage takeoff and the compound-miter trigonometry are public; the stock length and spring angle are user-supplied.
Estimate. AHJ and licensed professional govern.
Field names used by the API: perimeter_ft, openings_ft, waste_pct, stock_len_ft, net_ft, pieces, miter_deg
- Linear footage (perimeter - openings) x (1 + waste%), pieces = ceil(net / stock)finish-carpentry practice
- Corner cuts 45-deg miter for base/casing; crown miter/bevel from the spring anglecompound-miter geometry
- Verify on site cut a scrap and measure the actual wall anglesscope of this tile