Carpentry Math: Board Feet, Rafters, Stairs, Framing & Material Takeoffs

What you'll build

What you will be able to do

Each lab ends with a concrete result that you build yourself and the checker confirms, cell by cell.

• Turn six plan lengths from Cedarline Builders' garage-workshop drawings (in decimal feet) into inches, round them to the nearest 1/16 inch and split them into the feet, inches and sixteenths you read on a tape.
• Price Cedarline Builders' lumber list: board feet per piece and per line, the cost of each line, and the order total with sales tax and delivery.
• Count the studs, plates and header stock for the five walls of Cedarline Builders' garage workshop.
• Compare six roof pitches for the 24 ft wide garage: the pitch angle, the rafter length from plate to ridge, the length with the overhang, and a chart of how the rafter grows with the pitch.
• Lay out five stairs for the garage workshop: the number of risers for an illustrative maximum riser height, the actual riser height, the treads and total run, and a check against tread and comfort limits.
• Take off the sheathing and drywall for the garage workshop: net areas after openings, whole sheets with a 10 % waste factor, the cost per surface and the total.
• Take off a 20 × 12 ft deck: joists at 16" o.c., board rows with a gap, boards from 12 ft stock, screws per joist crossing, whole boxes and the material cost.
• Turn Cedarline Builders' takeoff into a price for the garage workshop: labour cost per category, price with overhead and profit, the resulting margin, and a stacked column chart of materials vs labour.