Story compliance

[CGH]

Story compliance.

I have an existing project that is Construction Classification VB with a proposed change of occupancy from [M] to proposed non-sprinklered.

Existing building originally built as a 2-story residence with cellar and “attic” and is now considered Historic.

The height from the finish “attic” floor to the exterior ridge of the hip roof is approx. 14ft.

The “attic” space will be used for storage and to terminate new elevator shaft approx. 5 ft from finish “attic” floor.

Building complies for height and area but according to The 2020 BCNYS table 504.4 a non-sprinklered building is limited to 2 stories for a occupancy. Designer states that the “attic” is not a “story” and does not have “habitable” space.

For # of stories compliance, what constitutes a “story?” Does this “attic” or this space above the second floor that is approx. 14ft high counts as a story? Please explain rationale, thanks.

 

[RLGA]

I'm confused about the change of occupancy. You say "from [M] to proposed non-sprinklered," but non-sprinklered what? Group B? Group R? Was it sprinklered before?

 

[CGH]

I'm confused about the change of occupancy. You say "from [M] to proposed non-sprinklered," but non-sprinklered what? Group B? Group R? Was it sprinklered before?

Proposed use is a bank. This building currently has no sprinklers.

 

[CGH]

Proposed use is a bank. This building has no sprinklers.

 

[Sifu]

The IRC has provisions that might allow the attic to not be considered a story if all the criteria are met. However you can't use the IRC for a bank. I don't think there is a similar allowance in the IBC. The dimensions you give may not tell the whole story but it sounds like your attic space would be large/tall enough to be converted to habitable space if so desired. I am thinking it is a story, just as any unused or unoccupied floor would be in a building but I am very interested in the responses of the experts on the forum, as my AHJ has a lot of similar homes/historic properties that are converting to commercial use.

 

[Mr. Inspector]

2015 IBC definition:

STORY ABOVE GRADE PLANE. Any story having its
finished floor surface entirely above grade plane, or in which
the finished surface of the floor next above is:
1. More than 6 feet (1829 mm) above grade plane; or
2. More than 12 feet (3658 mm) above the finished
ground level at any point.

i always went by if the floor surface was finished. There is no definition of what a finished floor is. Not sure if it means the floor is finished being built or something like hardwood, tile or carpet?

 

[Tim Mailloux]

2015 IBC definition:

STORY ABOVE GRADE PLANE. Any story having its
finished floor surface entirely above grade plane, or in which
the finished surface of the floor next above is:
1. More than 6 feet (1829 mm) above grade plane; or
2. More than 12 feet (3658 mm) above the finished
ground level at any point.

i always went by if the floor surface was finished. There is no definition of what a finished floor is. Not sure if it means the floor is finished being built or something like hardwood, tile or carpet?

If they are going to use the Attic for storage I would assume it has some sort of floor, I would then probably consider it a story.

 

[ChrisCampbell]

I believe the definition you need to consider here is "Story":

STORY. That portion of a building included between the upper surface of a floor and the upper surface of the floor or roof next above (see "Basement," "Building height," "Grade plane" and "Mezzanine"). A story is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters.

If the attic in question has a finished floor, will be used for storage and has a 14' height, my guess is that most AHJs across the country would call it a story. It certainly appears to meet the definition above.

 

[e hilton]

If they are going to use the Attic for storage I would assume it has some sort of floor, I would then probably consider it a story.

Unless the floor is solely for equipment access. HVAC maintenance.

 

[cda]

Story compliance.

I have an existing project that is Construction Classification VB with a proposed change of occupancy from [M] to proposed non-sprinklered.

Existing building originally built as a 2-story residence with cellar and “attic” and is now considered Historic.

The height from the finish “attic” floor to the exterior ridge of the hip roof is approx. 14ft.

The “attic” space will be used for storage and to terminate new elevator shaft approx. 5 ft from finish “attic” floor.

Building complies for height and area but according to The 2020 BCNYS table 504.4 a non-sprinklered building is limited to 2 stories for a occupancy. Designer states that the “attic” is not a “story” and does not have “habitable” space.

For # of stories compliance, what constitutes a “story?” Does this “attic” or this space above the second floor that is approx. 14ft high counts as a story? Please explain rationale, thanks.

How will the attic be accessed ??

stairway

or

pull down?

 

[cda]

Under IBC

if stairs to attic

and

used for storage, seems like a floor

Than there is that pesky fire code, people forget about:::

315.3.4 Attic, Under-Floor and Concealed Spaces

Attic, under-floor and concealed spaces used for storage of combustible materials shall be protected on the storage side as required for 1-hour fire-resistance-rated construction. Openings shall be protected by assemblies that are self-closing and are of noncombustible construction or solid wood core not less than 13/4 inches (44.5 mm) in thickness. Storage shall not be placed on exposed joists.

Exceptions:

1. Areas protected by approved automatic sprinkler systems.
2. Group R-3 and Group U occupancies.
3. 
   

Seems if you have to meet ifc that only makes a case for story stronger

 

[CGH]

I believe the definition you need to consider here is "Story":

STORY. That portion of a building included between the upper surface of a floor and the upper surface of the floor or roof next above (see "Basement," "Building height," "Grade plane" and "Mezzanine"). A story is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters.

If the attic in question has a finished floor, will be used for storage and has a 14' height, my guess is that most AHJs across the country would call it a story. It certainly appears to meet the definition above.

Thanks for this explanation.

 

[CGH]

How will the attic be accessed ??

stairway

or

pull down?

Stairway.

 

[CGH]

Stairway.

 

[CGH]

Under IBC

if stairs to attic

and

used for storage, seems like a floor

Than there is that pesky fire code, people forget about:::

315.3.4 Attic, Under-Floor and Concealed Spaces

Attic, under-floor and concealed spaces used for storage of combustible materials shall be protected on the storage side as required for 1-hour fire-resistance-rated construction. Openings shall be protected by assemblies that are self-closing and are of noncombustible construction or solid wood core not less than 13/4 inches (44.5 mm) in thickness. Storage shall not be placed on exposed joists.

Exceptions:

1. Areas protected by approved automatic sprinkler systems.
2. Group R-3 and Group U occupancies.
3. 
   

Seems if you have to meet ifc that only makes a case for story stronger

ok.

 

[CGH]

ok.

 

[Tim Mailloux]

So we got a stairway up to the attic, its got a floor and will be used for storage. I would say not only do you have yourself 3 story builing on your hands but you might also be looking at a mixed use building (Business & Storage).

 

[CGH]

So we got a stairway up to the attic, its got a floor and will be used for storage. I would say not only do you have yourself 3 story builing on your hands but you might also be looking at a mixed use building (Business & Storage).

Didn't think of that . I will check the square footage to see if it can be classified as accessory to the Business, thanks.

 

[CGH]

I will check the square footage to see if it can be classified as accessory to the Business, thanks.

 

[Tim Mailloux]

I will check the square footage to see if it can be classified as accessory to the Business, thanks.

Accessory to the B on the floor below?

 

[Mr. Inspector]

So by the definition of story every attic is a story even when the rafters are less then 6' above the finished floor? I don't think so.

What does it mean by finished floor? The group of inspectors I work for defines it as the floor having some kind of finish. If it meant that the floor is finished being constructed it would just say floor, you wouldn't have a floor at all if it wasn't finished being constructed. If it just meant any kind of floor it would not say a finished floor.