Second Stairway/ladder
Question on building code. We have a loft in our family room that has access from the second floor (but stairway is on the other side of the house). Brainstorming ideas for a stairway/ladder type access for it from the family room. Does the code for rise/run apply to a second stairway? Or can we do something steeper to not eat up as much room? If it is more storage area vs habitable space, does that change things?
Trying to figure out what bounds we need to work in on this. Thanks!
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Josh,
What code are you under?
We are under the IRC 2018
Josh, different building inspectors interpret it differently, but most I've worked with say that if the loft meets the definition of a habitable space then it needs an egress stair. This is the definition of a habitable space: https://codes.iccsafe.org/content/IRC2018/chapter-3-building-planning#IRC2018_Pt03_Ch03_SecR304.1. If there is less than 7' of headroom over a 70 sq.ft. area, it's not considered habitable.
This section says that habitable rooms need egress stairs: https://codes.iccsafe.org/content/IRC2018/chapter-3-building-planning#IRC2018_Pt03_Ch03_SecR311.4.
If you need an egress stair but the room area is less than 200 sq.ft, you could use an alternating tread stair: https://codes.iccsafe.org/content/IRC2018/chapter-3-building-planning#IRC2018_Pt03_Ch03_SecR311.7.11. They are awkward to use but could be worse, and take up about half the floor area of a conventional stair. Or you could use a spiral stair.
Josh,
As long as you already have a code compliant egress stair, we have always been allowed a secondary non-conforming one. If the IRC is silent on that possibility you should definitely run it by your inspector.
Thanks for the help! Wanted to know a little bit about what our options are before talking to the inspector.