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Mixed Use Occupancy Fire Sprinkler Requirements

brizoun1

Registered User
Joined
Jan 14, 2020
Messages
18
Location
Missouri
We are in the process of building a 6000 square feet two story building. The first floor, 3000 square feet, will have a classification as Business Group B consisting of office space. The upstairs is classified as Residential R-3. A one hour fire rated ceiling will separate the first and the second story and a one hour fire rated wall will separate the two dwellings upstairs. What areas need to be sprinkled and what NFPA sprinkler system can I use? NFPA 13, 13R, or 13D? I appreciate your input.
 
Normally when you have an R,,,

You sprinkle the entire building

I am thinking full NFPA 13 for first floor and 13R for 2nd
 
And still say 13 on first 13R on 2nd



1.1* Scope. A.1.1 NFPA13D is appropriate for protection against fire hazards only in one- and two-family dwellings and manufactured homes. Residential portions of any other type of building or occupancy should be protected with residential sprinklers in accordance with NFPA 13 or in accordance with NFPA 13R
 
Check your book to see if same wording


903.2.8 Group R

An automatic sprinkler system installed in accordance with Section 903.3 shall be provided “””””. throughout all buildings with a Group R fire area. “””””

My book has the same wording, but if I continue reading I it leads me to think that only the top floor needs sprinkled. 903.2.1 says an automatic sprinkler system installed in accordance with Section 903.3.1.3 shall be permitted in Group R-3 occupancies. 903.3.1.3 says automatic sprinkler systems installed in one and two family dwellings, group R-3, group R-4 Condtion 1 and townhouses shall be permitted to be installed throughout in accordance with NFPA 13D. The reason why I was thinking the R-3 portion is the only portion that needs sprinkled is because of the way 508.1, Mixed Use and Occupancy reads. Each portion of a building shall be individually classified in accordance with section 302.1. Where a building contains more than one occupancy group, the building or portion thereof shall comply with the applicable provisions of Section 508.2, 508.3 or 508.4, or a combination of these sections. Since we are using 1 hour fire partitions and walls shouldn't this be considered to have separated occupancies? If so, according to section 508.4.1 Occupancy Classification, separated occupancies shall be individually classified in accordance with Section 302.1. Each separated space shall comply with this code based on the occupancy classification of that portion of the building. Group B occupancy doesn't require fire sprinklers but R-3 does. That's what led me to believe I only needed an NFPA 13D system on the second floor.
 
And still say 13 on first 13R on 2nd



1.1* Scope. A.1.1 NFPA13D is appropriate for protection against fire hazards only in one- and two-family dwellings and manufactured homes. Residential portions of any other type of building or occupancy should be protected with residential sprinklers in accordance with NFPA 13 or in accordance with NFPA 13R

If I'm understanding separated occupancies correctly 508.4 the two dwellings on the second story shall be classified as type R3 completely independent from the first floor and shall comply with the codes based on the R3 occupancy only.
 
For 13D

I posted the scope

Your building is outside of the scope of 13D,,,

So it cannot be installed.
 

That's an identical situation as mine. I'm just trying to get clarification on this matter and it helped reading that thread. My whole dilemma is that my building inspector approved the plans with no provisions for a fire sprinkler system. He even issued the building permit. Our financing was secured and construction had already began and then we receive a letter in the mail stating we have to have a sprinkler system installed. I feel like it was his mistake that he overlooked it not having a sprinkler system, therefore we shouldn't have to add one at this point. Adding $35,000.00 to install a sprinkler system puts us way over budget and that's not feasible. I'm curious how this would be handled in other jurisdictions.
 
That's an identical situation as mine. I'm just trying to get clarification on this matter and it helped reading that thread. My whole dilemma is that my building inspector approved the plans with no provisions for a fire sprinkler system. He even issued the building permit. Our financing was secured and construction had already began and then we receive a letter in the mail stating we have to have a sprinkler system installed. I feel like it was his mistake that he overlooked it not having a sprinkler system, therefore we shouldn't have to add one at this point. Adding $35,000.00 to install a sprinkler system puts us way over budget and that's not feasible. I'm curious how this would be handled in other jurisdictions.


Read the fine print.

Yes we did review your plans, but if we missed something, you still have to build it to every section of the code.

Mosts cities will not let something like that slide.

On the other side whoever drew the plans for you, should know all aspects of the code, and designed it to code.
 
@ ~ @ ~ @

brizoun1,

FWIW, ...I agree with **cda** !.........Also, it may be time to

speak with your lawyer to see which direction you will need to
go regarding plan design errors.


You may want to have a discussion with the municipal Fire Chief
to confirm the sprinkler system throughout both floors, or s/he
may have another option.

@~ @ ~ @
 
As stated perversely throughout is the whole building, not the use
NFPA 13 2007


upload_2020-1-15_8-44-1.png


upload_2020-1-15_8-46-5.png
Review of a set of plan does not give permission to violate any coded sections
IBC 2101
upload_2020-1-15_8-30-48.png
Second, do not pit the Fire Chief against the Building Department, if the authority is in the Building Commissioner the FC probably only has review authority, like wise if in the community the FC has the authorly, the BC may have limited responsibility
 
@ ~ @ ~ @

I drew the plans myself on a computer program. When I presented them to the inspector he accepted them saying he didn’t require engineered drawings as long as the builder was okay with a basic floorplan. He had me write on the plan that the building would include a one hour fire rating between floors. He never mentioned anything about a fire sprinkler needing to be added.


brizoun1,

FWIW, ...I agree with **cda** !.........Also, it may be time to

speak with your lawyer to see which direction you will need to
go regarding plan design errors.


You may want to have a discussion with the municipal Fire Chief
to confirm the sprinkler system throughout both floors, or s/he
may have another option.

@~ @ ~ @
 
Uses get separated by fire barriers, not fire partitions....I'm in the throughout camp.....we have had previous discussions on 13R throughout the building when the R drives the sprinkler requirement....
 
@ ~ @ ~ @

brizoun1,

FWIW, ...I agree with **cda** !.........Also, it may be time to

speak with your lawyer to see which direction you will need to
go regarding plan design errors.


You may want to have a discussion with the municipal Fire Chief
to confirm the sprinkler system throughout both floors, or s/he
may have another option.

@~ @ ~ @


I drew the plans myself on a computer program. When I presented them to the inspector he accepted them saying he didn’t require engineered drawings as long as the builder was okay with a basic floorplan. He had me write on the plan that the building would include a one hour fire rating between floors. He never mentioned anything about a fire sprinkler needing to be added.
 
I drew the plans myself on a computer program. When I presented them to the inspector he accepted them saying he didn’t require engineered drawings as long as the builder was okay with a basic floorplan. He had me write on the plan that the building would include a one hour fire rating between floors. He never mentioned anything about a fire sprinkler needing to be added.
Are you trained in building design and code interpretation (architect/engineer/etc.)?
 
Are you trained in building design and code interpretation (architect/engineer/etc.)?

Absolutely not, and I never claimed to be. I drew the floor plans to give to an architect to have engineered drawings designed. The inspector accepted the basic floor plan so an architect was never solicited.
 
Absolutely not, and I never claimed to be. I drew the floor plans to give to an architect to have engineered drawings designed. The inspector accepted the basic floor plan so an architect was never solicited.


Is this a one horse town?? One inspector
 
To create a separate fire area for the "R" will require a 2 hour horizontal separation and 2 hour supporting construction. You are then only required to sprinkle the "R" occupancy
TABLE 707.3.10
FIRE-RESISTANCE RATING REQUIREMENTS FOR
FIRE BARRIERS, FIRE WALLS OR HORIZONTAL
ASSEMBLIES BETWEEN FIRE AREAS

It will probably be cheaper to provide a sprinkler throughout the entire building
 
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