Separated occupancy floors A-3 and B , max story area

[blugosi]

I have an existing A-3 two story occupancy (19th century historic building) connected on two levels to an existing three story addition built in 1924 (also historic building) which has office space supporting the main occupancy and I am trying to evaluate its compliance with IBC.

Unfortunately, the existing construction type floor area limits are much less than the actual floor areas of both occupancy floors, even after retrofitting sprinklers.

We can separate the A-3 from the B occupancy with 1 hour fire barrier per the requirements of table 508.4. Even if I treat them as separate occupancy , the sum of the ratios of the building area of each separated occupancy divided by the allowable building area of each separated occupancy exceeds 1, so that doesn't help much.

Would upgrading the fire rating of the fire barrier between the two occupancy floor areas allow me to evaluate each side of the barrier interdependently in terms of floor area?

What would be a proper path to address this? Upgrading the construction type is not easy mostly due to thin concrete slabs.

 

[Paul Sweet]

Is the Existing Building Code adopted where this project is?

 

[steveray]

Depends on what you are trying to do.....Why do you think you need to meet todays code or why are you assessing it to todays code?

 

[blugosi]

All parts of the existing building have been built before any Fire Code was applied.
It does not fully meet any Greek Fire code, old or new, regarding structural fire ratings, egress arrangements etc.
There is now a project to add more floor-space, as well as modify existing areas.
The AHJ agreed to review deviations from the Greek Fire Code as long as they are properly justified, and if the final fire protection strategy meets the IBC or NFPA 5000 requirements, it will be accepted.
Otherwise it will all be subjective.
I hope this clarifies things.....

 

[blugosi]

Is the Existing Building Code adopted where this project is?

Not directly, and I am not sure it makes sense taking the EBC into account because, if I am not mistaken, the EBC applies on buildings which met the Code applicable when they were built.
In my case, the building never complied with any Fire Code because there wasn't any in Greece back in the day.

 

[Yankee Chronicler]

Not directly, and I am not sure it makes sense taking the EBC into account because, if I am not mistaken, the EBC applies on buildings which met the Code applicable when they were built.
In my case, the building never complied with any Fire Code because there wasn't any in Greece back in the day.

If there was no code in effect, the building complied with all applicable codes at the time of construction.

When you say "add more floor space," are you referring to expanding the building footprint horizontally, adding a story or stories, or infilling vertical openings/atriums?

 

[blugosi]

If there was no code in effect, the building complied with all applicable codes at the time of construction.

When you say "add more floor space," are you referring to expanding the building footprint horizontally, adding a story or stories, or infilling vertical openings/atriums?

I understand your argument, but existing travel distances are up to 740 feet, non sprinklered , and more similar examples.

I cannot recommend something so far away from the common fire protection principles simply because when it was built there was no Code.

Schools visit the area, I would not send my 6yo kid to such an excursion.

The expansion is horizontal, doubling the original footprint and adding two basements.

 

[Yankee Chronicler]

Since you are in Greece, I don't know what your codes are. Has Greece adopted the ICC family of codes? If so, how extensively were they amended during adoption?

Stripping away legalese, the fundamental principal underlying the IEBC is "don't do anything that makes it less safe than it is today." Under the IEBC, additions must comply with requirements for new construction under the IBC. Alterations depend on the IEBC compliance method chosen by the applicant.

 

[blugosi]

Since you are in Greece, I don't know what your codes are. Has Greece adopted the ICC family of codes? If so, how extensively were they amended during adoption?

Stripping away legalese, the fundamental principal underlying the IEBC is "don't do anything that makes it less safe than it is today." Under the IEBC, additions must comply with requirements for new construction under the IBC. Alterations depend on the IEBC compliance method chosen by the applicant.

As far as I know, the ICC codes are not adopted in any European country, and they will probably never will.
However, in most European countries there are provisions for deviations from the local Fire Codes.
In Greece and other countries, the criteria are subjective and the responsibility always lies with the EOR.
If things go south, unless the EOR proves that his proposal did not reduce the level of safety compared to meeting the prescriptive code, he is the one to take the fall.
If however the EOR demonstrates that the deviation still meets a respectable international code, such as the one used successfully in the USA, the judge is not expected to claim that the American Code is not safe.

I can have the addition meet Code, i.e. go for Type IB construction which permits unlimited floor area for sprinklered building.
Going back to my original question, how do I approach the existing building (part A-3 part B) since the A-3 occupancy seamlessly merges into the addition? What could I do if IBC/IEBC were applicable?

 

[arwat23]

Not directly, and I am not sure it makes sense taking the EBC into account because, if I am not mistaken, the EBC applies on buildings which met the Code applicable when they were built.
In my case, the building never complied with any Fire Code because there wasn't any in Greece back in the day.

Assuming you have no Historical Building Codes, the building complies with the applicable codes at the time it was constructed. Any alteration or addition will need to comply with the IEBC or other codes applicable to existing buildings.

An addition or change in occupancy would trigger fire separation requirements (assuming fire separation is required for the occupancies). However, I don't really know how the historical building classification alters this, if at all.

Here in California, our Historical Building Code can limit the requirements for life-safety if the alteration or addition is for historical purposes (i.e., rebuilding a portion of the building that was removed previously). If the addition is not for historical purposes (i.e., additional floor space for more functionality), then the addition needs to comply with the IEBC and IBC.

IEBC Ch 11 requires the addition to comply with new construction requirements, so you'll probably need fire separation. I believe the existing portion of the building only needs to meet the requirements of Ch11 unless those existing spaces are being altered.

 

[blugosi]

Assuming you have no Historical Building Codes, the building complies with the applicable codes at the time it was constructed. Any alteration or addition will need to comply with the IEBC or other codes applicable to existing buildings.

An addition or change in occupancy would trigger fire separation requirements (assuming fire separation is required for the occupancies). However, I don't really know how the historical building classification alters this, if at all.

Here in California, our Historical Building Code can limit the requirements for life-safety if the alteration or addition is for historical purposes (i.e., rebuilding a portion of the building that was removed previously). If the addition is not for historical purposes (i.e., additional floor space for more functionality), then the addition needs to comply with the IEBC and IBC.

IEBC Ch 11 requires the addition to comply with new construction requirements, so you'll probably need fire separation. I believe the existing portion of the building only needs to meet the requirements of Ch11 unless those existing spaces are being altered.

Makes sense. The addition can easily meet code. The existing building will undergo significant alterations such as change of use from office and storage to assembly. If there were no modifications, I would not touch it and I would have no liability for it since it has been approved sometime in the 1950s when we still had a king and queen.
If I separate the new from existing with 1 hour fire barrier and 45 minutes rated doors, wouldn't that still need to comply with 508.4? How can I go around that obstacle?

 

[arwat23]

Makes sense. The addition can easily meet code. The existing building will undergo significant alterations such as change of use from office and storage to assembly. If there were no modifications, I would not touch it and I would have no liability for it since it has been approved sometime in the 1950s when we still had a king and queen.
If I separate the new from existing with 1 hour fire barrier and 45 minutes rated doors, wouldn't that still need to comply with 508.4? How can I go around that obstacle?

Separation between the old and new would need to comply with IBC 508.4. No way around as far as I'm aware.

Change in occupancy of the existing building could require compliance with IBC Ch 9 (IEBC 1011.2). Refer to IEBC 1011 for requirements when there's a change of occupancy classification. Means of egress will also need to be upgraded to comply with Ch 10 of the IBC based on your description (IEBC 1011.5.1).

I recently had a project in an existing building where we have a change of occupancy. New M occupancy on the ground floor (area of work) and existing R occupancy above (not in contract). We had two choices: either we provide a 2-hour separation or add sprinklers.

Edit: Correction - change in occupancy classification of a historic building should comply with IEBC 1204.

 

[Yankee Chronicler]

Can you introduce an actual fire wall to separate the addition from the existing building? Under the IBC, that would allow you to treat the addition as a separate building, so its area would not be added to the area of the existing building.

 

[blugosi]

Can you introduce an actual fire wall to separate the addition from the existing building? Under the IBC, that would allow you to treat the addition as a separate building, so its area would not be added to the area of the existing building.

Do you mean a three hour fire wall extending from the bottom of the building to the top?
Self supporting?
That I am not sure I can do because it would probably require demolishing existing bearing walls.
If this is the case, I need to take this up with our structural engineer…..
Adding some protection to the existing wall to bring it up to 180 minutes fire rating might be feasible.

 

[Mr. Inspector]

Do you mean a three hour fire wall extending from the bottom of the building to the top?
Self supporting?
That I am not sure I can do because it would probably require demolishing existing bearing walls.
If this is the case, I need to take this up with our structural engineer…..
Adding some protection to the existing wall to bring it up to 180 minutes fire rating might be feasible.

You could simply build a new wall next to and outside of the existing wall to make a 3-hour fire wall.

 

[steveray]

This work for you?

1011.6.1.1​

In other than Groups H, F-1 and S-1, fire barriers and horizontal assemblies constructed in accordance with Sections 707 and 711, respectively, of the International Building Code shall be permitted to be used in lieu of fire walls to subdivide the building into separate buildings for the purpose of complying with the area limitations required for the new occupancy where all of the following conditions are met:

1. 1.
   The buildings are protected throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 of the International Fire Code.
2. 2.
   The maximum allowable area between fire barriers, horizontal assemblies or any combination thereof shall not exceed the maximum allowable area determined in accordance with Chapter 5 of the International Building Code without an increase allowed for an automatic sprinkler system in accordance with Section 506 of the International Building Code.
3. 3.
   The fire-resistance rating of the fire barriers and horizontal assemblies shall be not less than that specified for fire walls in Table 706.4 of the International Building Code.

Exception: Where horizontal assemblies are used to limit the maximum allowable area, the required fire-resistance rating of the horizontal assemblies shall be permitted to be reduced by 1 hour provided that the height and number of stories increases allowed for an automatic sprinkler system by Section 504 of the International Building Code are not used for the buildings.

 

[steveray]

I think there is some confusion as the term "addition" was used, but it is an existing addition if I understand correctly....Which makes adding a fire wall much more complicated....

 

[Yankee Chronicler]

I think there is some confusion as the term "addition" was used, but it is an existing addition if I understand correctly....Which makes adding a fire wall much more complicated....

I understood the question to include creating a new addition as well as performing alterations and partial chance of use/occupancy within the existing building.

 

[steveray]

I understood the question to include creating a new addition as well as performing alterations and partial chance of use/occupancy within the existing building.

I have an existing A-3 two story occupancy (19th century historic building) connected on two levels to an existing three story addition built in 1924 (also historic building) which has office space supporting the main occupancy and I am trying to evaluate its compliance with IBC.

 

[Yankee Chronicler]

Oops.

Sorry. I blame it on my meds ...