Stair Tread Calculator
Calculate board feet of lumber or number of pre-made treads for your staircase. Compare costs for oak, pine, poplar, and composite stair treads.
Lumber Requirements
Cost Estimate — Oak
How It Works
Enter the number of treads, width, depth, nose overhang, and select your material. The calculator computes the total board feet of lumber needed and estimates cost by material type.
Board feet is the standard lumber measurement: (width × depth × count) ÷ 144. The nose overhang is added to the tread depth since you need that extra material.
Pre-made treads are sold individually and come in standard widths. They are often more convenient but may cost more than milling your own from raw lumber.
Composite treads are priced per tread since they are not sold by the board foot. They are ideal for exterior or high-traffic applications.
Frequently Asked Questions
What is the standard stair tread depth?
The IRC requires a minimum tread depth of 10 inches (measured from nosing to nosing). A standard 2×12 board is 11.25" deep, which with a 1" nose overhang gives a 10.25" effective tread depth — comfortably above code minimum.
How much does a stair tread overhang (nosing)?
The tread nosing typically overhangs the riser by 3/4" to 1-1/4". The IRC requires between 3/4" and 1-1/4" of nosing projection. A 1" overhang is the most common choice for residential stairs.
What is the best wood for stair treads?
Red or white oak is the most popular hardwood for interior stair treads due to its durability, attractive grain, and resistance to wear. Pine is a budget-friendly option for carpeted stairs. For exterior stairs, pressure-treated lumber or composite materials are best.
How do I calculate board feet for stair treads?
Board feet = (width in inches × depth in inches × number of treads) ÷ 144. Include the nosing overhang in the depth measurement. For example, 13 treads at 36" wide × 12.25" deep (11.25" + 1" nose) = 38.6 board feet.