• Welcome to The Building Code Forum

    Your premier resource for building code knowledge.

    This forum remains free to the public thanks to the generous support of our Sawhorse Members and Corporate Sponsors. Their contributions help keep this community thriving and accessible.

    Want enhanced access to expert discussions and exclusive features? Learn more about the benefits here.

    Ready to upgrade? Log in and upgrade now.

Accessory Storage???

JigglyPuff

JigglyPuff

REGISTERED
Joined
Mar 30, 2021
Messages
16
Location
Twin Cities
So I have an existing 2 story building that I'm working on. First floor are apartments (R-2 occupancy) and a restaurant (A-2 occupancy). Second floor are apartments (R-2 occupancy). The apartments will remain as is but we are turning the restaurant into a bunch of Offices (B occupancy).

My client would like to turn two of the offices into Storage rooms that will be for the apartments' use only. From a code perspective, can I call these storage rooms an Accessory Storage and if so, are they an accessory to the B or R-2 occupancy?


Per the 2020 Minnesota Building Code:
311.1.1 Accessory storage spaces
A room or space used for storage purposes that is accessory to another occupancy shall be classified as part of that occupancy.
 
For them to be accessory the aggreagate area of both storage rooms needs to be 10% or less of the area of the occupancy they are accessory to. As an example if your first floor R2 occupancy totals 5000sf, you would be limited to 500sf total area of accessory storage.
 
Tim Mailloux said:
For them to be accessory the aggreagate area of both storage rooms needs to be 10% or less of the area of the occupancy they are accessory to. As an example if your first floor R2 occupancy totals 5000sf, you would be limited to 500sf total area of accessory storage.
Click to expand...
Got it. I should be good. The total R-2 square footage is 13,000sf. The two storage rooms added up equals 192sf.
 
This was a change in the 2018 IBC that I thought was needed; however, I wish they would have used a term other than accessory. As Tim mentions, the use of accessory would send most people to Section 508.2 for accessory occupancies. However, that is not the intent of Section 311.1.1.

To be considered an accessory occupancy per Section 508.2, spaces considered as accessory occupancies are required to be classified individually. As an example, if a Group S-1 is considered an accessory occupancy per Section 508.2, then it is still classified as a Group S-1 but is not required to be separated from other occupancy groups or be limited in height per Table 504.4.

If a storage occupancy is considered "accessory" per Section 311.1.1, then it is not classified as a Group S occupancy, but rather as a part of the occupancy group to which it is considered "accessory."

I much prefer the use of ancillary in situations like this to avoid confusion with accessory occupancies.
 
RLGA said:
This was a change in the 2018 IBC that I thought was needed; however, I wish they would have used a term other than accessory. As Tim mentions, the use of accessory would send most people to Section 508.2 for accessory occupancies. However, that is not the intent of Section 311.1.1.

To be considered an accessory occupancy per Section 508.2, spaces considered as accessory occupancies are required to be classified individually. As an example, if a Group S-1 is considered an accessory occupancy per Section 508.2, then it is still classified as a Group S-1 but is not required to be separated from other occupancy groups or be limited in height per Table 504.4.

If a storage occupancy is considered "accessory" per Section 311.1.1, then it is not classified as a Group S occupancy, but rather as a part of the occupancy group to which it is considered "accessory."

I much prefer the use of ancillary in situations like this to avoid confusion with accessory occupancies.
Click to expand...
Agreed, that would have been much better for the code langauge. Sounds like a code change proposal for the next code cycle??
 
RLGA said:
This was a change in the 2018 IBC that I thought was needed; however, I wish they would have used a term other than accessory. As Tim mentions, the use of accessory would send most people to Section 508.2 for accessory occupancies. However, that is not the intent of Section 311.1.1.

To be considered an accessory occupancy per Section 508.2, spaces considered as accessory occupancies are required to be classified individually. As an example, if a Group S-1 is considered an accessory occupancy per Section 508.2, then it is still classified as a Group S-1 but is not required to be separated from other occupancy groups or be limited in height per Table 504.4.

If a storage occupancy is considered "accessory" per Section 311.1.1, then it is not classified as a Group S occupancy, but rather as a part of the occupancy group to which it is considered "accessory."

I much prefer the use of ancillary in situations like this to avoid confusion with accessory occupancies.
Click to expand...
Question for folks on this thread--does the square-footage of storage spaces considered accessory per Section 311.1.1 count towards the 10% max aggregate of accessory occupancies per 508.2.3? I'm surprisingly not finding any rock-solid clarification of this anywhere in the code or online. I know they took the 100 sf limit off the storage as accessory in the 2019 code, but it isn't clear if it is still part of the 10 percent limitation in 508.2.3,
 
rdh3t said:
Question for folks on this thread--does the square-footage of storage spaces considered accessory per Section 311.1.1 count towards the 10% max aggregate of accessory occupancies per 508.2.3? I'm surprisingly not finding any rock-solid clarification of this anywhere in the code or online. I know they took the 100 sf limit off the storage as accessory in the 2019 code, but it isn't clear if it is still part of the 10 percent limitation in 508.2.3,
Click to expand...
My interpretation: Section 508.2.3 applies to spaces classified as Group S occupancies per Section 508.2.1. Storage spaces that comply with Section 311.1.1 are not classified as Group S.

Thus, they would not be included in the 10% limitation per Section 508.2.3.
 
RLGA said:
My interpretation: Section 508.2.3 applies to spaces classified as Group S occupancies per Section 508.2.1. Storage spaces that comply with Section 311.1.1 are not classified as Group S.

Thus, they would not be included in the 10% limitation per Section 508.2.3.
Click to expand...
Awesome, thanks for the clarification, that is my interpretation as well. The rubber will meet the proverbial road when I resubmit the permit docs in a week. I'll make a note to circle back here and give an update to let folks here know if it was sucessful in my AHJ (Napa County). Thanks again!
 
steveray said:
But if they are accessory to the R2, do they need 1hr separation from the B?
Click to expand...
If the accessory storage areas are part of the dwelling units, then yes per the dwelling unit separation requirements. If they are storage rooms separate from the dwelling units but are for use by the residents, then it depends on whether you are using accessory (Section 508.2), separated, or nonseparated occupancies. If using the separated occupancies method, then yes, an occupancy separation would be required since the storage rooms are classified as Group R-2 if Section 311.1.1 is used, and no if the nonseparated or accessory (Section 508.2) occupancies method is used.
steveray said:
And do they need to be sprinklered if the R is?
Click to expand...
Per Section 903.2.8 (2018 IBC), a sprinkler is required throughout all buildings with a Group R. So, yes, a sprinkler would be required whether or not the storage rooms are classified as Group R-2 per Section 311.1.1.
 
Reviving this old thread -because my scenario is still clear as mud

A building (M) with 2 large storage areas (well over 10% of the building area) that if separate would be classified as S-2 (Porcelain and Pottery) -would I be able to apply section 311.1.1 or would that not qualify as accessory to the main occupancy?
 
VAC said:
Reviving this old thread -because my scenario is still clear as mud

A building (M) with 2 large storage areas (well over 10% of the building area) that if separate would be classified as S-2 (Porcelain and Pottery) -would I be able to apply section 311.1.1 or would that not qualify as accessory to the main occupancy?
Click to expand...
Are the storage areas (for porcelain and pottery) connected to the primary occupancy (Group M)? Does the porcelain and pottery have a direct relationship to the mercantile sales area (i.e. is the storage area for overflow/restocking?

If the answer to both of the questions above is yes, then I would say that the storage areas, although exceeding 10% of the building area (and thus unable to follow 508.2), may comply with 311.1.1 and be classified as part of the M occupancy.

This would be similar to a grocery store. The occupancy for the whole store is Group M; although, the back-of-house storage area for holding delivery and overflow prior to stocking may exceed 10% of the floor area.
 
classicT said:
Are the storage areas (for porcelain and pottery) connected to the primary occupancy (Group M)? Does the porcelain and pottery have a direct relationship to the mercantile sales area (i.e. is the storage area for overflow/restocking?

If the answer to both of the questions above is yes, then I would say that the storage areas, although exceeding 10% of the building area (and thus unable to follow 508.2), may comply with 311.1.1 and be classified as part of the M occupancy.

This would be similar to a grocery store. The occupancy for the whole store is Group M; although, the back-of-house storage area for holding delivery and overflow prior to stocking may exceed 10% of the floor area.
Click to expand...
Thank you. I understand.
The storage space(s) are not accessory to the store. They are 2 rooms accessible from a common (back) corridor with the store, but unrelated.
So in that case, separation (508.4) would be required... correct.
Thanks again!
 
VAC said:
Thank you. I understand.
The storage space(s) are not accessory to the store. They are 2 rooms accessible from a common (back) corridor with the store, but unrelated.
So in that case, separation (508.4) would be required... correct.
Thanks again!
Click to expand...
Correct, that is how I would look at it. Not accessory/ancillary to the store, then separation per 508.4.
 
You must log in or register to reply here.
Back
Top