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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Does a fire pump on an NFPA 13D system require backup power?

It seems like it should, but 13D does not say that it has to and does not reference NFPA 20.

Thanks in advance.

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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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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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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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We have a house (single family home) that will require an NFPA 13D system, but it is not going to be connected to city water.

There is a well onsite. The well completion report does not provide a pressure or flow output.

Can the well be used as part of the hydraulic calculations? What data would be necessary to incorporate it?

If not, I'm assuming that both a pump and tank would be needed here for the 13D system?

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My understanding is that when using residential concealed sprinklers in a single-family (residential) home, there is an exception to beams - that we space as if they are not present.

This is in the living room (image below). I think the plan reviewer is looking for sprinklers within each bay. My reading of the code was that concealed sprinklers cannot be lowered, so I disregarded the beams.
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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 single-family home NFPA 13D system.

What is the proper way to calculate a 13D system? Is this a 2- or 4-sprinkler calculation?

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There always seems to be controversy about residential sprinklers in the garage.

I recently came across a section in the 2018 IRC under Section 309.5 and it states that private garages shall be protected by fire sprinklers (must be residential or quick response, designed to 0.05 gpm/sqft density) where the exterior wall has been designed based on Table 302.1(2) Note A.

This table addresses minimum fire resistance ratings for exterior walls. Note (a) allows fire separation distance for non-rated exterior walls and projections to be reduced to 0-feet, unlimited openings and penetrations, with a setback, where residential subdivisions are all sprinklered.

While looking at that table, I am not sure how to verify on the sprinkler plans if the garage meets that design method.
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I have started asking the contractor to add a note on the plans regarding the design method and if they use this table and note to design the wall then sprinklers are required in the garage.

How would you interpret this section for compliance?

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13, 13R, 13D: Calculations and High Ceilings

I was reading through NFPA 13 (2016 ed.) and caught Section 8.10.2.2:
Residential Sprinklers shall not be permitted to be used on ceilings with slopes greater than 8 or 12 or ceiling heights greater than 24 feet unless specifically listed for this purpose.

This got me curious about how it affects NFPA 13R and 13D, checking into those I didn't see any restrictions where residential sprinklers stop being allowed at the ceiling height, however the maximum 24-ft ceiling was noted in NFPA 13D (2019) 10.2.1 and NFPA 13R (2019) 7.1.1.3.1 in regards to design sprinklers.

So am I correct in assuming that if you have a residence with a 24'-1" foot ceiling in the family room (say there's a loft second floor), that you now have to calculate and design the space per NFPA 13 rather than 13R or 13D (as that ceiling height is outside of the scope of 13R and 13D)?

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When are standard response sprinkler heads a better choice than quick or fast response heads (5mm vs. 3mm bulb)?

Are there applications where it would be preferable to have a slower response time?

As far as I know, quick and standard response heads cost the same, come with the same k-factors, and the same temperature ratings.

Why would the slower one be chosen? When would you choose a Tyco TY-B instead of a TY-FRB?

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Is there a minimum distance clearance required or recommended from the fire sprinkler and the top of a stacked washer dryer in small closet?

What is the reason for the clearance needed?

I heard that 4” is needed for the clearance rather than the standard 18” in a public area.

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Does the 'small room rule' apply to NFPA 13D sprinkler systems?

I could not find any mention of it in 13D. If 13D does not allow it, why not?

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Per NFPA 13D 2019 Edition Section 8.2.1.3, "Concealed Sprinklers shall be permitted to be installed in beams not greater than 4 in. (100mm) in depth."

Semi-recessed heads can be permitted to be installed in beams up to 14in.

Why do concealed sprinklers installed in beamed applications have a 4 inch limitation? 

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Where exactly does a hydraulic calculation need to end? 

When we run a hydrant flow test, there's a static/residual hydrant and a flow hydrant. I regularly run my hydraulic calculations from the building, through the service main, to a street main, and then up the tee'd branch that serves a hydrant so that my source point is exactly at the elevation of the static/residual hydrant. I do this so that I make sure to account for the proper elevation of the water supply.

Most other hydraulic calculations I see will end wherever the building's service main intersects with the street's supply. Is this correct? Wouldn't that place the source at an elevation lower than what the hydrant indicated is available?

Wondering what the proper way is that I should be precisely calculating systems. Thanks in advance.

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Why does a townhouse which is 4-story require an NFPA 13R system?

The IRC is specifically geared toward one-and two-family dwellings up to 3 stories, but the IBC allows 13D systems in R-3, R-4 condition 1 and townhouses (903.3.1.3).

Is there another prevailing code reference that overrules this allowance?

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I have an inspector who wants me to prove that calculating run or through tees is appropriate for 13 Residential systems.

I showed them that run tees are in 13D, he thinks they should be calc'd in 13? How do I prove something is not in a code?

Any help would be appreciated.

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Does the proximity to a residence and the number of windows make a difference in which system is used (NFPA 13 vs 13R vs 13D)?

​What are those requirements that make it change?

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Residential single-family dwelling is getting an NFPA 13D sprinkler system with a pump and water storage tank. 

Is the test line required to be routed to the exterior, or can it be run back to the water storage tank? I've seen it both ways but don't see an applicable code section.

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