Category
Framing & Carpentry calculators
The carpentry side of a build: how many studs to order for a wall, how much lumber a project needs in board feet or linear feet, and how to lay out a staircase that meets IRC code on the first try. Volumetric and dimensional take-offs, with a configurable waste factor that matches industry practice.
All Framing & Carpentry calculators
Staircase Calculator
Riser height, tread depth, stringer length and IRC code check for straight stairs.
Board Foot Calculator
Board feet for any quantity of dimensional or hardwood lumber, with optional cost.
Wall Stud Calculator
Count studs, plates and openings for a framing wall at 12, 16 or 24 OC.
Plywood Calculator
Plywood, OSB or sheet good count for any area in 4×8, 4×10 or 4×12 sheets.
Nominal vs actual lumber sizes
A “2×4” is not actually two inches by four. After kiln-drying and surfacing, a nominal 2×4 measures 1½″ × 3½″. For framing layout and stud counts that does not matter — spacing and wall length are what drive the numbers. For board-foot pricing on softwood, industry convention uses nominal dimensions; for hardwood sold by volume at the sawmill, use the actual rough dimensions (4/4 = 1″, 5/4 = 1¼″, 8/4 = 2″).
16″ vs 24″ on center
Wall studs at 16″ on centre is the residential standard for load-bearing walls in IRC jurisdictions. 24″ OC is permitted with 2×6 advanced-framing (OVE) on exterior walls and on non-load-bearing partitions. 12″ OC appears in heavy-load applications (multi-storey above grade, point-load transfer walls).
Staircase code, in one paragraph
IRC 2021 §R311.7 sets the residential limits: maximum riser 7¾″, minimum tread 10″, minimum width 36″ clear of handrails, minimum headroom 6′-8″, and maximum variation between any two risers of ⅜″. Stairs with four or more risers require a handrail at 34 – 38″. Our staircase calculator flags any value that exceeds these limits before you cut a single stringer.