# Interior and basement stairs

> Building and fixing stairs inside the house. Ask with your Sheet attached: homeowners who’ve done it and verified pros answer, and anyone can read it.

## Before you ask

The floor-to-floor height, the opening, and the headroom.

- **Attach your Sheet** so people see your sizes and the math.
- **Your town is enough.** Never your address; check photos for house numbers and plates.
- **Is it safe?** A safety question here goes to pros verified in general contracting or carpentry, unless you pick another trade. Only they can call it safe or unsafe.

## Build interior or basement stairs

Inside stairs, 8′ 9″ rise: 14 risers of 7-1/2″, 13 treads, 4 stringers (2×12 × 16′) and 11′ 4-1/2″ of floor space.

What people get wrong:

- **Measuring the rise before the finish floors.** New flooring at the top or bottom makes the first or last step taller or shorter than the rest — measure finished floor to finished floor.
- **Forgetting to drop the stringer.** The bottom step ends up 3/4″ taller than the rest.
- **Headroom checked only at the top step.** The tightest spot is under the opening’s edge: measure 6′ 8″ straight up from the nosing line there.

[The worked example, every line's math and the code notes](https://studsheet.com/sheets/istairs) · [Your own sizes in the app](https://app.studsheet.com/p/istairs)

## More in Stairs

- [Deck and porch stairs](https://studsheet.com/forum/deck-stairs): Stringers, landings and outside steps
- [Concrete steps](https://studsheet.com/forum/concrete-steps): Pouring and facing concrete steps
- [Steel and spiral stairs](https://studsheet.com/forum/steel-and-spiral-stairs): Steel, spiral and floating stairs
- [Railings and guards](https://studsheet.com/forum/railings): Deck, stair and balcony railings: wood, metal and glass
- [Every group](https://studsheet.com/forum#every-group)

## How the community works

- **Open to read** from anywhere, no account needed.
- **Sign in with your email** to ask, answer and vote. No password.
- **The best answers rise:** votes, “worked for me” and a solved mark. Verified pros carry a badge.

Questions? Write to [support@studsheet.com](mailto:support@studsheet.com).