We have a 4-story apartment building with commercial units on the first floor, residential on all floors above.

The architect is providing a 2-hour separation at the 2nd floor deck (concrete on a metal deck), and is requesting NFPA 13 for the 1st floor and NFPA 13R for the units above.

The AHJ came back and requested NFPA 13 for the corridors and elevator lobbies on floors 2-4 to avoid separation of elevator lobbies from corridors, but still keep the draft/smoke control doors at the hoistways.

Can NFPA 13 and 13R be mixed on the upper levels?

Is this approach valid from a code-standpoint?

Is there validation or different approaches that would need to take place to make this happen?

Thanks in advance.

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We have an NFPA 13R (2019), 4-story apartment. It's Group R-2, Class V-A construction, with open interior breezeways hallways in "garden style". Combined, all floor levels are ~60,000 sqft (~15,000 sqft per floor).

The design includes one 320 sqft storage room and about four 55 sqft storage closets in the interior breezeway per floor that tenants can rent if they choose.

All storage rooms and closets have gypsum ceilings.

From what I can tell, NFPA 13R-2019 doesn't really address storage like this, so I'd assume to revert back to NFPA 13 in order to protect? Is that a correct approach?

Due to the combustible construction - would that trigger coverage above and below ceilings in these spaces?

And then - am I permitted to tie into an NFPA 13R system, or would this even need a separate riser?

We could have two scenarios - one with rooms 2-hour fire resistance rated from the R-2, and another where it's incidental and not separated.

Thanks in advance for your input.

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We have a rehab of a two story with a walk out basement where they are going to expand the basement level and make it mercantile with the two upper floors being R-2.

This is Type V-B construction and they are proposing to 1-hour horizontal to separate the mercantile from the R use. They are wanting to use the standpipes as their sprinkler risers.

My question is three-fold:
1. Can they sprinkler the entire building with 13R, or
2. Can they omit sprinklers completely in the mercantile if they separate from the R use by 1-hour (the mercantile by itself would not require sprinkler protection,
3. Can they sprinkler the mercantile with 13 and the R use 13R without a rated separation?

I am an AHJ and only wanting to require what the Code requires. I am having trouble deciphering the requirements.

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In the stairway, on the 2nd floor only of 4-story wood-framed condo (NFPA 13R), do we require a sprinkler on the “extended landing” ?

In the attached image Blue is the sprinkler in question, red are the required sprinklers.

The main floor requires coverage because it has two entrances / exits from the stairway. The upper floor has full protection of the entire area. The 3rd floor does not require protection as the 4th floor does not have a extended landing. So this only applies to the 2nd Floor.

Thanks in advance.

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Does NFPA 13D require trapped air to be removed in a sprinkler system?

In the 2016 NFPA 13, Section 7.1.5, Air Venting - a single air vent for a sprinkler system, with a connection conforming to 8.16.6, shall be provided in each wet pipe system utilizing metallic pipe.

I am using CPVC with anti-freeze in most residential systems.

Is there a code requirement for a vent for what I'm doing?

Thanks in advance.

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Do you include a loss in your flow-through tees (the straight run) on CPVC for NFPA 13R or NFPA 13 Systems?

We're finding a loss through one software provider's default setting, whereas another by default does not include a loss on the flow-through CPVC tees. We'd like to find the correct approach.

Thanks in advance.

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​I am in the process of bidding an existing building.

Here is the rundown: the ground level has parking. Above that is a 3-hour horizontal separation between the parking and the first floor. Then there are three stories of apartments above the separation.

I’m looking at this as two separate buildings and am proposing NFPA 13 for the parking and NFPA 13R for the apartments above.

What concerns should I have about hanging from old wood?

Like very old wood, almost petrified?

I'm doing an NFPA 13R job for an old historic building that has been moved. I don't know how old, but it uses full dimension wood. The 2x's look like they measure 2-inches thick.

I'm wondering what hanging to this old dry wood is going to be like?

Do they need to predrill? Are screws better?

Any ideas appreciated!

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With the use of CPVC, what are the limits to how much can be exposed?

I had thought that we needed to have all of the pipe concealed, and I can't see in code how this is addressed.

We have a project with a temperature-controlled and insulated attic (the mechanical engineer has confirmed it will be kept above 40 degrees F year-round) in a warm climate. This is in an NFPA 13R apartment building.

Is CPVC allowed to be run exposed through the combustible attic space?

The attic is not sprinkler protected (NFPA 13R system, 3-story, apartments, smaller-sized project). Thanks in advance.

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Can non-residential sprinklers be used in a NFPA 13R design?

NFPA 13R lists that residential sprinklers are permitted for use but does not list they are required to be used.

My understanding is that sprinklers used in NFPA 13 for light hazard would exceed or meet sprinkler requirements within NFPA 13R

On this premise, would installing a sprinkler for light hazard occupancy be exceeding NFPA 13R minimums, and thus be acceptable?

We have a dry sprinkler system we are installing in a small existing dormitory built with combustible construction.

We are using a NFPA 13R design approach which avoids sprinklering the attic space, with local AHJ approval. We need to have concealed sprinklers under request of the owner based on the occupancy, but there are not residential concealed dry pendent sprinklers, and the contractor is pushing to install recessed dry residential sprinklers.

Thanks in advance.

​

The installation contractor and I have had an argument about how sprinklers should be spaced and calculated in a 13R system.

I have argued that per NFPA 13R Section 7.1.1.3.1, we should calculate 3 sprinklers in the greatest hydraulic demand area. This area is furthest from the riser and the calculation permits 16x16-ft spacing for the area that has the most sprinklers.

Section 7.1.1.3.1:
For each of the following situations, the number of sprinklers in the design area shall be all of the sprinklers within a compartment, up to a maximum of four sprinklers, that require the greatest hydraulic demand:

The contractor wants to remove a sprinkler in a single room and move a sprinkler 10 feet off of the exterior wall, but in NFPA 13R makes no mention of a single sprinkler proof calculation that could justify such a move.

There is no mention of a single sprinkler calculation in NFPA 13R permitting a spacing of 20x20, and so all sprinklers on the project can be only 16x16 if the greatest hydraulic demand is permitting it.

In NFPA 13D, it makes no mention of a single sprinkler calculation either, but does refer to single sprinkler operations in A.10.1. I did not feel comfortable designing a sprinkler system that was not up to code standards and need an outside opinion on this matter. Thanks in advance.

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In the 2015 International Building Code, Section 101.2:

The provisions of this code shall apply to the construction, alteration... of every building or structure in any appurtenances connected or attached to such buildings or structures.

Exception: Detached one- and two-family dwellings and multiple single-family dwellings (townhouses) not more than three stories above grade plane in height with a separate means of egress, and their accessory structures not more than three stories above grade plane in height, shall comply with the International Residential Code.

The debate: Why in the world are we going to allow them to label this design as residential?

The townhouse exception is seemingly being used pretty loosely around the building department.

In our college community, these structures meet the requirements of a townhouse, but with obvious intent to be student housing.

After looking at code....I cant say I blame these designers. I see no way to combat their argument. They meet all the code requirements to avoid the extra costs of a 13R system and only have to add an additional layer of gyp to comply!?

If I am missing something, please let me know! Maybe I just need to accept them as townhouse?

It sure doesn't "feel" right. 

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We are a sprinkler contractor running into a new situation for an apartment building. The apartment is designed under NFPA 13R.

We have an inspector requesting that we firestop a draft stop from the corridor into an apartment.

Can you point us in the right direction whether this is required?

I'm dealing with a situation now where we are completely renovating an old mixed-occupancy property and the plans were drawn and approved with a 2-inch incoming service for both the residential domestic water and the fire suppression system.

Now that the fire sprinkler contractor is ready to install, and the fire chief reviewed plans for the 2-inch pipe, the fire chief says he won't approve it unless we install a minimum of 4-inch incoming pipe from the main.

The architect says the city already approved the pipe size. Fire Marshal says no.

Anyone have code/insight to support either way?

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I am designing a fire sprinkler system for a 5-story residential apartment building.

The building is Type V wood truss construction with 16" open web wood trusses.

The floor/ceiling assembly is a one-hour fire-resistance-rated construction (UL listed). Sheetrock is attached directly to the bottom of the joists with wood subfloor on top. The ceiling is inaccessible (concealed).

The question of sprinkler above the ceiling has come up. I don't see a need for them. There is 6" sound batting above the ceiling.

The Fire Marshal does not allow NFPA 13R design. It an NFPA 13 design.

Is this space required to be protected?

Any input would be helpful, thanks in advance.

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I have a project with four separate apartment buildings with 4-units in each building.

All buildings identified as R-3 Occupancy, Type V-B Construction, single story. There are demising walls between each unit that are 1-hour fire-resistance-rated including a 1-hour draft stop between each unit.

The Architect has noted on the approved plans, "Fire Sprinklers Per NFPA-13D".

My question #1: would NFPA-13D be allowed in these 4-unit buildings?

These are not townhome style zero lot line buildings built independent to one another. I think the project should be designed according to NFPA-13R.

Question #2: One building has a unit designated as a "Laundry room and folding room". I think this single unit should be designed according to NFPA-13 under Ordinary Hazard Group-1, correct?

Thanks in advance for your feedback!

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Assuming that it's been approved by a structural engineer, is there any code or standard restrictions that would prevent running CPVC branch pipe through a built-up floor beam?

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I cannot find a residential sprinkler that will allow for sloped ceilings greater than an 8/12 pitch.

How can we approach this and still provide proper protection in a residential property?

Most log cabins have ceilings with a pitch up to 12/12. Thanks in advance.

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I have a Type V-A Group R-2 apartment building whose code summary indicates as having four stories atop two levels of basement, all of the same construction and occupancy, and requiring a 13R system type.

I’m no expert in the building code, but it's my understanding that in order to have a building taller than four stories and still use 13R, a 3-hour horizontal assembly would be required having Type I construction below such assembly and up to four stories above; this building looks to be Type V throughout six levels with no horizontal assembly.

The large building is vertically separated into four individual buildings by 2-hour fire walls but I see no horizontal separation.

Is there a way this proposed 13R sprinkler system can be code compliant (IBC 2015)?

Thanks in advance.

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In Section 19.4.1.3(3) of NFPA 13-2019 Edition, discusses that rooms or compartments 800 sqft or less (small rooms) should be calculated based on delivering 0.10 gpm/sqft over the room or the compartment by using the area of the room divided by the number of sprinklers in the room.

I believe I've overcalculated remote areas in the past.

My project now is an apartment building designed according to NFPA 13. Using residential type sprinklers with non-sprinklered combustible concealed spaces. According to Section 19.4.1.2 I need to calculate a minimum of eight sprinklers.

In the past I've calculated the eight sprinklers using the actual spacing based on the S x L rules with a 0.10 gpm/sqft density.

One room example - room dimension of 24 x 12 is 288 sqft. Two sprinklers spaced in a compartment 8'-0" off one wall and 6'-0" from adjacent wall. Using the S x L rule: 16' x 12' = 192 sqft x 0.10 gpm/sqft = 19.2 gpm each.

Or, according to Section 19.4.1.3 (3), would I divide the room size 288 sqft by 2 sprinklers, which is 144 sqft per sprinkler, regardless of the actual sprinkler distance from the walls? This second scenario would result in a 14.4 gpm required flow.

Or, was the code option (3) assuming the sprinklers are evenly centered within the compartment.

Thanks in advance for your input and clarification.

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Can you run sprinkler pipe underground after the riser has entered the building?

The building we're working on is an apartment building that is being sprinklered to NFPA 13R (2016 Edition). The apartment is 4-story and has open air breezeways. There are dry sidewalls protecting the breezeways.

The owner wants to run pipe under the slab in the open air breezeways instead of providing a heated path for sprinkler pipe across the breezeway. I have strongly recommended against this, but have gotten pushback from the owner and contractor regarding this pipe arrangement.

Is this underground arrangement allowed?

I believe there are some cases where this is acceptable but not many. Thanks in advance!

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I have a mixed-occupancy, 100-year old 1-story house within a metro area. There is existing office space up in the front of the building, and a one-bedroom apartment in the back.

We are adding a camelback addition to the building. The existing office space will remain as is and we will have two 3-bedroom apartments in the back. The camelback will be set back 20-feet from the front of the house. The height of the building will be 30-feet. 

Can I use 13R or 13D in the residential units? 

Do I need any sprinkler in the commercial office space upfront?

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I purchased a house with fire sprinkler system that is 30 years old. The previous owner had the sprinkler disconnected about 10 years ago when a furnace repairman stepped on one of the sprinkler pipes. The damage was repaired but the water line to the sprinkler system was not reconnected (not sure why).

I was wondering if it would be okay to have it reconnected now?

It is a 30-year old system and has been inactive for 10 years.

Do the pipes become brittle are there other concerns in reconnecting?

Thanks for you help.

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I'm reviewing a apartment building that meets the requirements for an NFPA 13R system.

My questions: A pump is going to be required for this project and they are proposing to use a booster pump on the incoming waterline at the property line to reach the required pressure for domestic and fire demands.

Is a combined domestic/fire pump like this allowed?

It would be a private pump.

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In NFPA 13R, sprinklers may be omitted from bathrooms and closets provided they meet the area and size requirements, and are constructed with limited or non-combustible materials (gypsum/drywall).

Should sprinklers be installed in bathrooms and closets on the top floor regardless of area/size and construction to prevent a fire on the top floor from getting into the ceiling space and spreading?

I have seen other designers do this but I can't find any formal requirements for this approach.

Has anyone else ever done this? Would it matter if the ceiling and roof assembly were fire rated?

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