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Occupancy Group for Storm Shelter???

Papio Bldg Dept

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Jan 24, 2011
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Location
Papillion
I have a 540 SF, Type V-B, Storm Shelter attached to detached private residential garage building (10 garages @ 2,700SF).

The RDP is defining the storm shelter as a group U occupancy. Is this consistent with your experiences, or should it be some other occupancy group (e.g., A-3/B/etc.)?
 
I don't really see how you could assign any other occupancy to it. I think the charging statement at 312.1 describes this application exactly.
 
Papio,

See Section 303.1 from the 2006 IBC, Exception #3.

3. A room or space used for assembly purposes that is less than 750 square

feet (70 m2) in area and is accessory to another occupancy shall be

classified as a Group B occupancy or as part of that occupancy.

A Residential parking garage is classified as a S-2 (see Section 311.3)

Did your RDP provide a designed occ. load ?

.
 
"private residential garage building"

I was going off this in the OP, which would place the main use in a U, private garage.
 
A 2,700 sq ft Private Garage

Add 540 sq ft shelter you now exceed the allowable area for a "U" occupancy

Any Fire Walls? Above ground or below ground shelter. What is the shelter for? Short term, a few hours such as tornados or long term such as winter blizzards, flooding or hurricanes.

I am with Brudgers and I would be looking at an "A" for egress, You can cram a 100 people in pretty easily
 
See Section 406.1.2 - Area Increase, in the 2006 IBC for separation

requirements over 3,000 sq. ft.

As "mtlogcabin" stated, a fire rated wall would need to be constructed

for the area over the 3,000 sq. ft. threshold, of the existing detached

residential parking garage and the new storm shelter.

I WOULD however, want a high occ. load.

.
 
I haven't seen plans yet...trying to calculate Building Permit Fees and such for the application. I am assuming the storm shelter construction will provide a firewall condition, but that will be reviewed later (5,500SF = U OCC/V-B).

It appears to qualify for the 303.1, exception 3, making it a B occupancy, or as part of the accessory occupancy, which would be a U then?

I am considering A-3/B.
 
trying to calculate Building Permit Fees and such for the application
Percentage of the construction cost?

Very simple, don't care about constuction type or occupancy classifications.

It's consistant and easy for everybody.
 
Wouldn't it be an R-3 or accessory to it??

What is the occupancy of a garage attached to a house ????
 
Well, we all obviously have differing opinions on the "occupancy classification", I think we all agree that the OL should be based on worst case scenario, at 5 sf per occupant. I would think by design, a storm shelter would probably meet the requirements for a 2-hr separation to create a separate building. But again guessing, based on assumptions. (I know)
 
Even if a size exception or accessory use/same use as principle building is declared, the life safety (egress etc) elements need to be constant with the occupant load count of 1 per 5sf for an assembly space (unless they are going to furnish with beds/tables and chairs. . . .)
 
One other thing to consider if a high occ. load is used is the plumbing fixture

count. More occupants = more fixtures. 540 sq. ft. is not that large!

.
 
mtlogcabin said:
Percentage of the construction cost?Very simple, don't care about constuction type or occupancy classifications.

It's consistant and easy for everybody.
Unfortunately we use the ICC's Building Valuation Data (BVD) tables to calculate permit fees. This method determines a cost/sf based upon the construction type and occupancy group and then multiplies by the square footage to determine a construction cost valuation. This valuation is then multiplied by an area modifier to determine Building Permit Fees and Plan Review Fees.

With recent changes in the economy, labor costs have dropped significantly, and contractor's valuations no longer match up as they did two years ago.

It was consistant, but never easy for anybody.
 
globe trekker said:
One other thing to consider if a high occ. load is used is the plumbing fixturecount. More occupants = more fixtures. 540 sq. ft. is not that large!

.
The RDP does not believe that they need plumbing fixtures as it is for emergencies only. I had to fight, kick and scream to get an accessible route/entrance on the Civil/Utilities Permit. 540 square feet is only 108 occupants. I doubt they will even show the space as conditioned when they fully submit.
 
fatboy said:
Well, we all obviously have differing opinions on the "occupancy classification", I think we all agree that the OL should be based on worst case scenario, at 5 sf per occupant. I would think by design, a storm shelter would probably meet the requirements for a 2-hr separation to create a separate building. But again guessing, based on assumptions. (I know)
Thanks for your input. I am still considering all of the following occupancy groups: A3/B/S2/U.

Do you know if the 2012 or 2009 addresses storm shelter occupancy?
 
So if this house was being built brand new, and showed the storm shelter as part of the garage, would the entire project be reviewed under the Irc??

And permit fee based on the value of the house including storm shelter
 
cda said:
So if this house was being built brand new, and showed the storm shelter as part of the garage, would the entire project be reviewed under the Irc??And permit fee based on the value of the house including storm shelter
It is a 43 unit (R-2) apartment building with a detached 10 stall parking garage (S-2) & 540 SF storm shelter (A-3). It is reviewed under the IBC. When a storm shelter is provided (we have no ordinances, zoning or building requirement), we will review under the ICC 500.

If we were reviewing a house, the attached garage would be considered an S-2 (for valuation purposes only) in most cases because it would exceed the accessory definition allowing it be defined as an accessory or U occupancy. The garage and house would be reviewed under the IRC, and the storm shelter, when provided, under the ICC 500. A storm-shelter in an R-3 is typically going to meet the 10% sf rule, and would be classified as accessory.

Are there other or better ways to do this? Most likely, but this is what our administration approved through council. It is what it is I guess.
 
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