how wide are stairs

Typical residential stairs are usually 36 to 42 inches wide in the U.S., and many building codes set 36 inches as the minimum. Wider stairs are common for comfort, furniture moving, and a more open feel.

Quick Scoop

• Minimum common code width: 36 inches.

• Typical residential range: 36 to 42 inches.

• Wider, more comfortable stairs: 48 inches or more is often used in larger homes.

• Some UK new-build stairs: about 800 to 860 mm wide.

What it means

If you’re asking for a house staircase, a good rule of thumb is that 36 inches is the floor, 42 inches feels more comfortable. For public buildings or accessibility-focused designs, stairs are often wider than standard home stairs.

Simple example

A narrow basement stair might be built at 36 inches, while a main staircase in a modern home might be 42 to 48 inches so two people can pass more easily and large items are easier to carry.

Bottom line

If you need one number, use 36 inches minimum and 36–42 inches typical for residential stairs.