When Can I Use NFPA 13R?

MeyerFire University | FX101.09

By Joe Meyer, PE

RESOURCES

• Notes Page

RELATED VIDEOS:

• FX101.08 - When Can I Use NFPA 13D?
• FX101.10 - When Must I Use NFPA 13?

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TRANSCRIPT

When can I use NFPA 13R? 

13R is the standard for the installation of sprinkler systems in low rise residential occupancies.  

Now call me crazy but I think the committee wanted us to know where to use 13R with the title that they gave us.  

13R is intended for residential occupancies that are not particularly large or tall. 

The goal of NFPA 13R is to help detect and control residential fires which can then improve life safety and help prevent property damage. The purpose as listed in the standard itself and it talks both about life safety and preventing property damage. 

The end result of a 13R system is that it’s intended to prevent flashover where the fire originates and improve the chance for building occupants to get out of the building safely. 

Just like in NFPA 13D, the first limit for using this standard is the applicable building code. The second limit for using the standard is what is defined in NFPA 13R itself. However specifically with 13R systems, there’s a bit of a twist. 

A very important fair warning here is that this specific topic has been changing a lot in the past couple of code cycles and will likely continue to change in the next few code cycles. The use of NFPA 13 versus 13R is an active and ongoing hot topic for our industry. What we put together here today is what we know at this point in time based on the requirements of the 2021 International Building Code and what is in the 2019 version of NFPA 13R. 

The further we get in time from these specific editions, the more important it will be to go back and look up the applicable building code and latest building codes to see what the currently required system is when we talk about this topic. 

Again, this is changing all the time and the example I'm presenting today could be out of date very quickly. You can still follow these steps to see what is required for your project and your standard, but just be cognizant that this is an ever changing topic. 

One quick side tangent to consider that I've heard from experienced engineers who have been involved in litigation is that the building code and the standards don’t necessarily shield professionals from their responsibility for prudent engineering practice. 

I'm not a lawyer and I don't even pretend to play one on TikTok, so if you want to explore this in more detail I would definitely speak with an attorney. 

What I do know is that when an applicable building code or standard changes and it becomes more stringent overtime, we as a responsible design professional need to consider what is in that latest edition. Again, even though it’s not necessarily applicable to our project but we need to know what's in that latest edition and what it's telling us that might soon be required for future projects, let's say that the applicable building code is a 2018 IBC. 

For our building, we can use an NFPA 13R system, but in the latest building code which is 2021 edition, it would require us to use a 13 system. And this isn't necessarily true, but just as an example, go with me here. An NFPA 13 is a standard that offers a higher level of protection than 13R. 

In similar situations in the past, engineers have gotten sued and have lost lawsuits where they have only provided what the building code or the standard requires at a minimum and not what the latest industry standard is or what the standard of practices. This is just something to be aware of. 

What does this all mean for us today? 

Well, when it comes to making decisions on the standard that we use for our buildings, especially when it comes to 13 and 13R, check your applicable building code and do the code research, but then also check the latest building code and the latest standard for their limitations and what would be required if you're using the latest editions. 

If we know that in a very short period of time that a more robust system will soon be required, then it may be time to have that conversation with the building owner and let them know what the latest standards are requiring. 

Again, in this situation, it's not necessarily required, but it could be a good idea knowing what future code cycles will bring thinking about resale, the building or changing occupancy in the future. Now may be the time to go with a more robust system. 

In these situations when there are differences, again, the building code and the standard don't necessarily protect professionals. 

So for NFPA 13R, when can we use it? 

Let’s first look at the limits under the building code. As an example today we’re gonna be using the IBC 2021 edition without any local modifications. 

If we open the International Building Code 2021 edition and go to Section 903.3.1 for the installation standards, this is which sprinkler standard to use, we’ll get a clear picture of how these standards are applied. 

According to the building code, NFPA 13R is only allowed in group R occupancies, which are residential occupancies, which have to be four stories or less that’s above grade, the floor level of the highest story is   above the lowest level of fire department access, so where your firetruck pulls up, that lowest level measured all the way to your high story has to be 30 feet or less. And the lowest story of the building is 30 feet or less below the lowest level of fire department access. So again, the difference in a subgrade, a basement of a basement can't be 30 feet or low, 30 feet or lower than that fire department access. 

The IBC then goes on to make provisions talking about balconies and decks and corridors within the means of egress and addicts. And these requirements can differ from 13R itself. 

The international Building Code in this space is overriding the requirements of 13R. 

But these are the limits that are in the International Building Code which explicitly applies for 13R systems. 

But as we say on TV, wait, there's more! 

Let's say our building meets all of these limitations and could go 13R. Are we then good to use 13R under the building code? 

 Well, as engineers like to say, it depends. 

You see the difference between 13R and 13 is that 13R is the standard for residential occupancies that allows systems to be installed that are slightly more budget-friendly. They allow sprinklers to be omitted in areas that 13 might not allow. They allow a sprinkler density that’s half of light hazard out of NFPA 13, and even allow for your sprinklers to be calculated when you have a bunch of small compartments. 

So in short, 13R is less stringent than 13. 

The building code recognizes this. 

There are plenty of benefits and code kickbacks that come only with using an NFPA 13 system. The benefits and code kickbacks only come with using a 13 system, that more robust system. 

We know that sprinklers work very well. We have a great history of success in battling fires with automatic sprinklers. They're like having thousands of little firefighters with their hoses ready that go to work 24 hours a day, 365 days a year, and are ready to take the heat on as soon as you kick up the room to 200 degrees. 

We know sprinkler systems out of NFPA 13 offer major benefits to life safety and property protection. That can't be understated. 

The creators of the building code know this too. I say creators, the committees, the volunteers, our collective group of knowledge, we know this to be true too. 

The committees offer their very own incentive program where we can dangle all the benefits of a fully sprinklered building in front of architects and developers and building owners by offering some discounts in other areas. 

What are these kickbacks? 

Well, with a 13 system, we can build buildings taller with more stories, with larger floor areas, with reductions and fire resistance ratings, reduction in draft stopping requirements. We allow for more hazardous material storage. We allow unlimited area buildings in some cases. And we allow more openings and buildings and really a host of other kickbacks too. 

I also want to be very clear this isn't your local like back-alley tax-evader, that sitting in the dark, you know, doing a handshake. This is all above board. 

The building code spells it out for us what all these kickbacks are. 

Now it's not always easy as a checklist to go from top to bottom and say, I think we've got some organizations that have put together some good material on that. 

But what I'm trying to say is, you know, the building code does offer a reasonable number of benefits when you go to a fully sprinklered building, that's under NFPA 13 specifically. The thing is, though, if you're going to collect the dough, you got to provide the real deal. 

If you weren't born in the 80s, what I'm trying to say is that if you're gonna take advantage of all of the code kickbacks that come with NFPA 13 fully sprinkler building, the building actually has to be sprinklered with a 13 system. 

That should be obvious and go without saying, but these two parties are usually different. 

The architects and the code consultants are in one corner making decisions and going about their code analysis over here. But that's usually a separate group, then your sprinkler design team who may be under the contractor who's also trying to determine whether they can use the 13R system, especially when it comes to bidding. 

13R can have a substantial savings and contractor can win jobs if they go to 13R, but because they're two different parties that aren't necessarily talking, this area gets a little bit of tricky. You can't take all of the code benefits from a 13 system and still use 13R, it's one or the other. And that's the hard part. If you're a sprinkler contractor, it's not always easy to tell just by looking at the job, whether an architect or code consultant has used all the benefits of an NFPA 13 fully sprinklered building in their building code analysis. 

Sometimes, life safety plans will make it very clear whether NFPA 13 was used for any of these kickbacks. But sometimes, it's really in the weeds and requires a lot of looking at each code assumption piece by piece. 

My personal opinion is that if you're a sprinkler contractor who is bidding a job and you’re unsure whether an architect or code consultant used benefits for a 13 system, you really have to go ask them. Get it in writing whether and NFPA 13 system is required or whether an NFPA 13R system would be allowed based on the code approach for the building. 

Now, regardless of what IBC 903.3.1 would allow, if the architect or code consultant needs an NFPA 13 system in order to make the building code compliant than a 13 system is what is required. 

And again, this is not always obvious at face value. It really isn't the sprinkler contractor's responsibility to have to verify every single assumption that the architect makes just to comply with the building code. Sprinkler contractor should not be expected to be experts in the building code. They should be expected to be experts in sprinklers. 

My advice for this is if you come across a situation where you're designing or estimating or bidding a project, or unsure whether 13R can be used, submit an RFI to the design team and get it clarified so that it's very clear to all parties exactly what is being required in one for the building. 

If you're on the consulting side and you're working with an owner, educate them on what it means to have an NFPA 13 versus a 13R system. There have been major losses for buildings and even total building losses where entire addicts have been consumed in fires that resulted in total building tear downs that used an NFPA 13R system. If everyone is able to evacuate the building and the fire was relatively contained to the attic, then some might consider that an NFPA 13R success by the definition of the standard. Many building owners would probably feel differently though. Educating owners on the differences between 13 and 13R where you get protection, where you're not getting protection is kind of a prudent benefit of having a consultant on the job. That's what we're here for. That's what we need to educate.  

So, what have we determined so far? 

First is that if we're going to use an NFPA 13R system, the applicable building code has to allow it. 

Second is that we need to be sure the design team for the building did not use any code allowances for a 13 fully sprinklered building. If they did, then and NFPA 13 system needs to be provided. 

If our project still passes both those criteria where we could use a 13R system, then we have to check the standard itself. 

NFPA 13R limits itself to residential occupancies up to four stories in height and that are in buildings that do not exceed 60 feet above grade. 

So, we've talked about the building code, the use of code allowances for an NFPA 13 system, and we’ve talked about NFPA 13R requirements. 

That can be pretty straightforward if we have a clear single occupancy building. But what about when we get into institutional occupancies like and I1 or I2, or a building that is in our occupancy but has an accessory occupancy? Or what about a separated building, or a mixed occupancy building, or podium construction? 

These get a bit more complex. 

There are code paths for each of these and these tend to be much more complex applications which we will explore in more detail in the content ahead. 

I'm Joe Meyer, this is MeyerFire University.