Separation between different types of construction

[dooleybob41]

The 2000 edition of NFPA 101 contains the following:

8.2.1* Construction. Buildings or structures occupied or used in accordance with the individual occupancy chapters (Chapters 12 through 42) shall meet the minimum construction requirements of those chapters. NFPA 220, Standard on Types of Building Construction, shall be used to

determine the requirements for the construction classification. Where the building or facility includes additions or connected structures of different construction types, the rating and classification of the structure shall be based on either of the following:

1. Separate buildings if a 2-hour or greater vertically-aligned fire barrier wall in accordance with NFPA 221, Standard for Fire Walls and Fire Barrier Walls, exists between the portions of the building

Exception: The requirement of 8.2.1(1) shall not apply to previously approved separations between buildings.

2. The least fire-resistive type of construction of the connected portions, if no such separation is provided

I've been unable to find in the 2012 IBC a section that has requirements similar to the red and green text sections above. Can anyone point me to similar requirements in the IBC?

 

[cda]

Chapter 6?

602.1 General. Buildings and structures erected or to be erected, altered or extended in height or area shall be classified in one of the five construction types defined in Sections 602.2 through 602.5. The building elements shall have a fire-resistance rating not less than that specified in Table 601 and exterior walls shall have a fire-resistance rating not less than that specified in Table 602. Where required to have a fire-resistance rating by Table 601, building elements shall comply with the applicable provisions of Section 703.2. The protection of openings, ducts and air transfer openings in building elements shall not be required unless required by other provisions of this code.

602.1.1 Minimum requirements. A building or portion thereof shall not be required to conform to the details of a type of construction higher than that type which meets the minimum requirements based on occupancy even though certain features of such a building actually conform to a higher type of construction.

And

503.1 General. The building height and area shall not exceed the limits specified in Table 503 based on the type of construction as determined by Section 602 and the occupancies as determined by Section 302 except as modified hereafter. Each portion of a building separated by one or more fire walls complying with Section 706 shall be considered to be a separate building.

And

706.1 General. Each portion of a building separated by one or more fire walls that comply with the provisions of this section shall be considered a separate building. The extent and location of such fire walls shall provide a complete separation. Where a fire wall also separates occupancies that are required to be separated by a fire barrier wall, the most restrictive requirements of each separation shall apply.

 

[Dr. J]

There isn't.

This is one of the major differences between IBC and NFPA 101.

NFPA 101 allows a Fire Barrier to create a separate building. It takes a Fire Wall (structurally independent) to create a separate building in IBC. CDA's quotes are the evidence of that.

Even under NFPA 101 there is a subtle requirement for "vertically-aligned", meaning that in a multi-story building, the top of the lower floor's Fire Barrier must align with the bottom of the upper floor's Fire Barrier, but at least all the Fire Barriers can bear on the floor - a Fire Wall must be structurally independent.

 

[RLGA]

I agree with Dr. J. Only a fire wall can create separate buildings to allow the use of different construction types.

 

[cda]

I agree with Dr. J. Only a fire wall can create separate buildings to allow the use of different construction types.

Can you downgrade the existing construction type to the new ,,, if all the other variables work and nothing has to be done to the existing??

Kind of like the number 2 in 101

2. The least fire-resistive type of construction of the connected portions, if no such separation

 

[dooleybob41]

Not in this instance. Both buildings are existing and the least fire-resistive type of construction (Type V) is not now allowed for healthcare building construction. In fact it may never have been allowed (building was constructed in 1969) but I don't have a copy of the code from that time period to verify (and it doesn't matter, it is what it is). I think a contractor cut corners and didn't get caught.

 

[Dr. J]

Are you worried about I code AHJs or NFPA AHJs?

CMS/TJC/State enforce NFPA 101. NFPA 101 ch 19 does indeed allow EXISTING Type V construction, however it must be fully sprinklered, and is limited to 1 story for V(000) or 2 stories for V(111). This IS a retroactive provision. CMS/TJC WILL cite you if it is not sprinklered or over 1/2 stories . You also need the 2 hour Fire Barrier being discussed, or else Type V restrictions apply to the entire building. But at least it is possible to be perfectly legal this way as far as NFPA is concerned.

The I code enforcers (typically the local guys) is a different issue. Now we get in to the classic discussion of "was it ok when built" and "what triggers a code upgrade". Typically the I code enforcers do not have any retroactive authority until you want to do work triggering a code upgrade (then you are screwed). There is always some level of negotiation, but that should not even start unless the building is fully sprinklered.