Math at work · carpentry, worked out

The Framing Square

The math on a job site, one step at a time: feet, inches and sixteenths, board feet, stair risers and stringers, roof pitch and rafters, squaring a corner, studs on center, materials with waste, concrete by the yard and miter angles. Fractions on their own are on the Fraction Bar, plain unit changes on the Measuring Tape.

For learning and planning practice. Check your local building codes and the manufacturer’s numbers (coverage, yields, spans) before you build. The code numbers on this page are typical values, not the law where you live.

Lessons board feet stair rise and run rafter length how much concrete all Math at work lessons

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The work

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    Every tape-measure number is kept exact, as a fraction; where a length is rounded to the nearest 1/16 inch, the step says so.