A framing lumber calculator counts the studs, plates, headers, blocking and sheathing a wall needs from its length, height, stud spacing and openings, and a framing material calculator or lumber estimator does the same for the floor and the roof: joists, rim, subfloor, rafters or trusses. A free framing calculator gives the count; a house framing cost calculator prices it, and for a contractor the price is the count at the yard's sheet with waste, the crew's hours at a loaded rate, the crane or the lift, overhead and markup. The estimate template on this site is that second half, and a lumber calculator for wall framing is its first input.
Walls: studs, plates, headers and blocking
Studs are the wall length divided by the spacing, rounded up, plus one, plus the extras every corner, intersection and opening adds: the king and jack studs at each side of a window or door, the cripples above and below, the corner assemblies. Plates are three times the wall length for a double top plate and a bottom plate, in the lengths that avoid short joints. Headers are sized from the opening span and the load, and blocking by the row. Count per wall and sum, because the offcuts do not travel.
Floors and roofs: joists, sheathing and the rest
Joists are the floor length divided by the spacing plus one, in the span length, with rim joist by the perimeter and blocking or bridging by the row; subfloor and wall sheathing are areas divided by the sheet with a waste allowance for cuts; rafters follow the same count as joists with the length from the run and the pitch, or trusses are pieces from the plan. Hangers, straps, nails and adhesive scale from those counts and are a line, not a rounding.
From the count to the cost
Price the count at the yard's current sheet by species and grade with a waste allowance the crew has measured, add the crew's hours from its own record per square foot of wall, floor and roof at a loaded rate, charge the crane or the lift by the day, then apply the overhead percentage and the markup. Pro on this site keeps the lumber estimate with the job, so the board feet bought and the board feet used become the next job's waste allowance.
Questions people ask about framing lumber calculator
How many studs does a wall need?
Length divided by spacing, rounded up, plus one, plus the king, jack and cripple studs at each opening and the extra studs at each corner and intersection; count per wall and sum.
What waste allowance should a lumber estimate carry?
One the crew has measured on its own jobs by comparing the yard ticket with the framing done; cut-heavy roofs and walls with many openings waste more than plain runs.
Is a house framing cost calculator the contractor's tool or the owner's?
Either can use the count; the contractor's version prices it at the yard's sheet with the crew's hours, overhead and markup, which is what the template on this site does.