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Basement stair height clearance

K

kjmass1

Registered User
Joined
Dec 20, 2021
Messages
21
Location
Boston, MA
My stairs to the basement only have 72" height clearance (1940s). If I wanted to make my basement finished/livable square footage, do the stairs need to comply or are they grandfathered in? No way I could get 80" without dropping basement floor. Is that a hard rule or judgement call by inspector?
 
How would you gain clearance by dropping the floor? Seems like you would need to enlarge the opening in the first floor.
 
e hilton said:
How would you gain clearance by dropping the floor? Seems like you would need to enlarge the opening in the first floor.
Click to expand...
Yeah I guess that wouldn’t help. Stairs are under first floor stairs so I think I’m pretty locked in there.
 
kjmass1 said:
Is that a hard rule or judgement call by inspector?
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I would do an onsite visit 1st to determine if there was a possibility of creating more headroom clearance, 72 inches is just not enough IMHO. I have agreed to 78" a couple of times but never lower than that
 
Go in and have a sit down with the building department.

Lots of 100 year house in our parts. I wrote a policy years ago, that if it required substantial structural modification, that I would accept existing stair conditions. Usually involved a site visit by me.

Then it was a judgment call on my part. (carpenter by trade)

R104.10 Modifications. Where there are practical difficulties
involved in carrying out the provisions of this code, the
building official shall have the authority to grant modifications
for individual cases, provided the building official shall
first find that special individual reason makes the strict letter
of this code impractical and the modification is in compliance
with the intent and purpose of this code and that such
modification does not lessen health, life and fire safety or
structural requirements. The details of action granting modifications
shall be recorded and entered in the files of the
department of building safety.
 
fatboy said:
Go in and have a sit down with the building department.

Lots of 100 year house in our parts. I wrote a policy years ago, that if it required substantial structural modification, that I would accept existing stair conditions. Usually involved a site visit by me.

Then it was a judgment call on my part. (carpenter by trade)

R104.10 Modifications. Where there are practical difficulties
involved in carrying out the provisions of this code, the
building official shall have the authority to grant modifications
for individual cases, provided the building official shall
first find that special individual reason makes the strict letter
of this code impractical and the modification is in compliance
with the intent and purpose of this code and that such
modification does not lessen health, life and fire safety or
structural requirements. The details of action granting modifications
shall be recorded and entered in the files of the
department of building safety.
Click to expand...
Thanks, this is very helpful. My inspector is very by the book, but reasonable.

Do you know who determines whether a basement is considered “finished/habitable/living” by tax assessment? (square footage is pricey here, I want it on the books) My inspector said I can finish it however I like, but certain things wouldn’t be to code. Does that mean it’s non-conforming, unfinished space by definition?

Or does the assessor not really care about that and if a basement has been renovated, they’ll call it finished square footage?
 
If you do alterations to your basement and leave the stairway alone the code does not require anything for the stairway.
You only need a permit for what you are changing.
 
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Does the main floor joist allow for 45° angle pieces of floor joist, sometime that will work if you modify the floor joist? I'm sure you checked that.

_____________l__l
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Rick18071 said:
If you do alterations to your basement and leave the stairway alone the code does not require anything for the stairway.
You only need a permit for what you are changing.
Click to expand...
What’s considered an alteration to the stairs? Carpet? New railings or replacing treads? Or just don’t change the layout.
 
Rick18071 said:
If you do alterations to your basement and leave the stairway alone the code does not require anything for the stairway.
You only need a permit for what you are changing.
Click to expand...
True enough but some padding is a good idea.
 
I would say yes, the stairs need to be brought to current code. The reason is that you are intensifying the use in the basement by making it habitable. If you can provide a second exit out of the basement, then the existing non-compliant stair can remain.
 
Robert said:
I would say yes, the stairs need to be brought to current code. The reason is that you are intensifying the use in the basement by making it habitable. If you can provide a second exit out of the basement, then the existing non-compliant stair can remain.
Click to expand...

The stairs have 80”+ almost everywhere, but a couple treads hit 78/79ish.

I have a 32” x 72” exit door that proceeds out under a deck and could also combine 2 windows to get the egress square footage. They are at 40” height.

https://imgur.com/a/7bHic30
 
TheCommish said:
Has the slab setted?
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For some reason, the middle area of the basement had another 3-4" slab poured on top of the existing one, and isn't level. It's weird, I know.

I'm getting an estimate to get that broken up and re-poured. I'm not going to like the estimate but I think that's the best way so it's not so tight with the clearances, and could hang drywall+strapping no problem.
 
steveray said:
In CT the State gives a pass on stair headroom to 6'1" for finishing an existing basement.....Ask you local inspector what they do...
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I have finished a basement a couple weeks ago here in Fairfield-CT and they didn't allowed me to use a stairway because 1 step was 6'3"... I had 10 steps that were ok, just 1 wasn't compliant.
 
Icaro Vasconcelos said:
I have finished a basement a couple weeks ago here in Fairfield-CT and they didn't allowed me to use a stairway because 1 step was 6'3"... I had 10 steps that were ok, just 1 wasn't compliant.
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It would almost be better if they were all 6’3”. People pay attention to the first couple of steps and then muscle memory take over. Visitors will bump their head. A well lit stairwell and a padded bump should make the difference in most cases but 6’3” is a real head knocker..
 
I would love to see the section in the IRC that would require someone to bring the basement stairway up to code or required a MOE when finishing a existing basement. Please provide it. I can only find a requirement for a Emergency Escape and Rescue Opening for when adding a bedroom in a existing basement.
 
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