Expert: Stephen Major - 6/4/2007

Question
QUESTION: Is there some formula that can be used to calculate the number of steps and their dimension. We turned a garage into a family foom and have steps that go down into a basement. From the new family room floor to the bottom of the basement we have to have uniform steps. Where do I start to measure and what is the formula? Any help would be appreciated. Thanks

ANSWER: Michelle,

There isn't a "formula" per se, but there  is a straighforward procedure.  If you can answer a few questions I will walk you through this.  

Plese give me the vertical height from floor to floor.

Will any thick flooring (like hardwood) be added to either level after the stairs are built?  If so, where and how thick.

What are the stair treads made of, and how thick will they be?

Is there any headroom obstruction, doorway, hallway, etc. that will limit the length of the stair run (horizontally)?  Or, how much length do you have available horizontally?

--Steve Major

---------- FOLLOW-UP ----------

QUESTION: Hi Steve,
The vertical height is 9' 3 1/4"
There will be no thick flooring, we'll just leave them bare until we pass inspection. After will probably be a thinner type carpet. I know the minimum riser according to our construction guy is 8 1/4". We will probably use 3/4" pine for the riser and tread.
The length horizontally is 10' 11".
The first step onto the landing (which hasn't been built yet has to be 7 1/2" because of a ledger board that sticks out. We could have it smaller than 7 1/2". We already have a railing up leading onto the landing, and are trying to stay within the confines of that. I understand the short the rise the more comfortable the ascent. Any help would be appreciated. Thanks.  

Answer
Michelle,

I received your dimensions.  Thanks.  For some reason I also got this last message from you six times, so I'll delete the other five.

Since a picture is worth a thousand words, I drew up a few quick sketches (4 slides in PDF format).  Please go to our website at:

http://www.stephenmajor.com/michelle.html

and click on the link.

Best of luck with this.  I'm sorry I can't give you a whole course in stairbuilding here (there's a lot to it, especially if you want it to come out right).  But hopefully the sketches will help.

--Steve Major