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Calcimator

Door Casing Calculator

Casing set count and material from door count.

About this calculator

Total Linear Feet is pure geometry -- door count times per-door casing length, itself built from door height, door width, casing width, reveal, and sides per door -- with no reference anywhere to Cost Per Linear Ft or Waste Factor. Cost Per Linear Ft and Waste Factor only enter downstream, when Linear Ft (with waste) and Material Cost are computed, so Cost Per Linear Ft stays completely inert against Total Linear Feet across its entire declared range, and so does Waste Factor. That split matters for reading the two footage outputs correctly: Total Linear Feet is the raw geometric quantity with no waste allowance, while Linear Ft (with waste) applies the Waste Factor multiplier on top -- the two will only ever match at 0% waste.

Sides Per Door (1 for one-sided/closet doors, 2 for both sides) doubles every per-door quantity when set to 2, including Total Miter Cuts and Casing Sets, since the calculator treats each side as an independent casing set. Door Height and Door Width both feed directly into the leg and header lengths that make up one casing set's linear footage, so raising either always raises Total Linear Feet, monotonically across their full declared ranges, with the header length also picking up a contribution from Casing Width and Reveal through the mitered-return allowance at each corner.

Inputs

ft
ft
in
in
%

Results

Total linear feet

164.47

Linear ft per door32.89
Linear ft (with waste)180.92
Total miter cuts40
Casing sets10
Material cost$361.85
How to Use This Calculator
  1. Enter Number of doors, Door height (ft), and Door width (ft).
  2. Set Casing width (in), Reveal (in), and Sides per door.
  3. Adjust Cost per linear ft ($), Waste factor (%) as needed.
  4. Review the Total linear feet result.
  5. Use Linear ft per door and Linear ft (with waste) to inform your decision.

How the result changes with Number of doors

Number of doorsTotal linear feet
2.598.68
3.75131.58
7.5263.16
13427.63

What each input means

Number of doors
Total doors needing casing.
Door height (ft)
Height of the door opening (standard is 6 ft 8 in = 6.67 ft).
Door width (ft)
Width of the door opening (standard is 2 ft 8 in = 2.67 ft).
Casing width (in)
Width of the casing profile in inches.
Reveal (in)
Setback from jamb edge to casing edge (typically 3/16 in).
Sides per door
1 for one-sided (closet) or 2 for both sides.
Cost per linear ft ($)
Price per linear foot of casing material.
Waste factor (%)
Extra material for cuts and waste.

What each result means

Linear ft per door
Casing material needed per door (both sides if applicable).
Total linear feet
Total casing material for all doors.
Linear ft (with waste)
Total footage including waste factor.
Total miter cuts
Number of 45-degree miter cuts at header corners.
Casing sets
Total casing sets (2 legs + 1 header each).
Material cost
Estimated cost for casing material.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Number of doors = 5, Door height (ft) = 6.67, Door width (ft) = 2.67, Casing width (in) = 2.25 = 8 input(s) provided
  2. Calculate Total linear feet
    Total linear feet = lfPerDoor * doorCount
    164.47 = 164.47
  3. Calculate Linear ft per door
    Linear ft per door = lfPerSide * sidesPerDoor
    32.89 = 32.89
  4. Calculate Linear ft
    Linear ft = totalLinearFt * (1 + wastePct / 100)
    180.92 = 180.92

Engine last updated . Checked against 2 independently-derived tests — how we verify calculators. Built by Paul Gunder, a software engineer, not a licensed financial, medical, or legal professional.

Frequently Asked Questions

Does raising the cost per linear foot change how much material I need?

No -- Cost Per Linear Ft only affects Material Cost, never Total Linear Feet or Linear Ft (with waste). The quantity of casing material needed is determined entirely by door dimensions, casing width, reveal, sides per door, and door count; price per foot only converts that quantity into a dollar figure.

Why are Total Linear Feet and Linear Ft (with waste) different numbers?

Total Linear Feet is the raw geometric quantity computed from door dimensions and casing specs, with no allowance for cutting waste. Linear Ft (with waste) applies the Waste Factor percentage on top of that raw figure -- the two values are identical only when Waste Factor is set to 0%, and diverge more as the waste allowance increases.

How much does setting Sides Per Door to 1 instead of 2 actually save?

It roughly halves Total Linear Feet, Total Miter Cuts, and Casing Sets, since the calculator treats each side of a door as an independent casing set (2 legs + 1 header). One-sided casing is typical for closet openings where the back side isn't finished; standard passage doors usually need both sides cased.

What drives the header length in each casing set?

Header Length starts from Door Width and adds twice the Casing Width plus twice the Reveal, to account for the mitered return at each top corner where the header meets the legs. A wider casing profile or a larger reveal setback both push header length -- and therefore Total Linear Feet -- up slightly beyond what door width alone would suggest.

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