Allow Omission for 55.4 sqft Bathrooms?

1/10/2022

I have a four-story hotel project to design that has bathrooms in the guest suites. These bathrooms measure out to 55.4 sqft per the architectural drawings of the bathrooms.

I am getting pushback from individuals as I don't feel this complies with NFPA 13-2016 Section 8.15.8.1.1's exception, and therefore it would require sprinklers.

I interpret the 55 sqft threshold as 55.00 sqft, or am I interpreting this incorrectly and should allow sprinklers to be omitted as long as the square footage does not break into the 56-sqft threshold?

The exception also states 5.1 square meters, which converts to 54.89 sqft, which to me, reinforces my 55.00 sqft threshold.

What are your thoughts and feedback?

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26 Comments

Anthony

1/10/2022 07:38:00 am

Code is code, it is the law.

Have them make the room 1/2 a sqft smaller and you can call it a day. Perhaps a 0-6'' x 1'-0 built in shelf? Fur out the wall the shower is on 3'' further?

If you are and AHJ and are allowing a variance I think it is a very reasonable one. However, sounds like someone trying to cut corners, probably a good time to take the magnifying glass out and check out the rest of the project to see where things may have been "missed."

Jim

1/10/2022 11:02:18 am

It's not the law.

sean

1/10/2022 01:30:39 pm

his intent is correct.

When the building code is adopted it is adopted into the local laws, and these new laws reference standards.

So to meet the law you need to meet the code and the standard

Alex

1/10/2022 08:06:26 am

I agree with Anthony. This is one of many cases that arise where people look to stretch the code "just this one time". Sadly, if you give way here, next time they will look for the heads to be just 8' off the wall.

I would hold true and push back on the architect to decrease the SQFT somehow.

Alex

Jesse

1/10/2022 08:09:39 am

2016 NFPA 13R says sprinklers SHALL not be required in bathrooms where the bathroom area does not exceed 55-sq. ft.

So the inverse would also be true: Sprinklers SHALL be required in bathrooms where the bathroom area exceeds 55-sq. ft.

In your case, the bathroom does in fact exceed 55 sq. ft. So you'll need to protect this bathroom unless they make it smaller.

Eric D.

1/10/2022 08:10:21 am

So as an AHJ and plan reviewer, 55 is 55. If it breaks the 55 SF mark (55.001), then sprinklers are required. Look at the past few days where sprinklers were not installed in buildings in Philly and NYC...high loss of life. If the architect wants to redesign the bathroom and reduce the SF to under 55 (as printed in black and white in the code/standard), then that is up to them. But if they leave it over 55 SF, then sprinklers must be dropped in to comply with the requirements.

Wes

1/10/2022 08:15:49 am

Just my opinion, but I think this is somewhat sloppy work by the architect.

I once had a code consultant say never to build a highest-occupied floor above 72-feet if you don't want to be a highrise.

Why 72-feet, and not the 75-feet threshold that code states? It's too easy for grade to change, or for details to get missed, or for the 'rounding' effect, or a sequence of small decisions to get awfully close to the 75-foot benchmark where the entire project has to be scrutinized.

If you're looking to meet the intent of code, then don't leave room for controversy or extra scrutiny. Make it clearly compliant. Don't make a 54-sqft bathroom, make it 52-sqft so there isn't any room for interpretation. Otherwise - comply with the more stringent requirement.

It's less of a factor of whether the 0.4 sqft fundamentally makes a difference. Does it? Probably not. But code has to draw a line somewhere. Don't get sloppy with design and this wouldn't have been an issue.

Wes

1/10/2022 08:17:00 am

Also, it's Monday morning and I really should finish my coffee before getting asked about cutting corners...

Brian Willis Spurrell

1/10/2022 08:24:48 am

Codes are written and adopted as minimum requirements key word being minimum. In Canada the National Building Code does not allow the omission of any room on the top floor.

Todd Wyatt

1/10/2022 08:27:28 am

A hotel is classified by the IBC as a Group R-1 Residential occupancy classification. Per 903.2.8 Group R, "an automatic sprinkler system installed in accordance with 903.3 shall be provided throughout all buildings with a Group R fire area." 903.3.1.1.2 Bathrooms lists an exception to sprinklers in Group R bathrooms "that do not exceed 55 square feet in area ... provided the walls and ceilings ... are of noncombustible or limited-combustible materials with a 15-minute thermal barrier rating."

NFPA 13R can be used in a Group R occupancy IF it meets the (3) condition per 903.3.1.2 (4 stories or fewer above grade plane, highest story = 30 feet or less above lowest level of fire department vehicle access, lowest story = 30 feet or less below lowest level of fire department vehicle access). The number of stories is based on the grade plane.

The IBC is the Code that determines the scoping requirements (including exceptions) for automatic sprinkler systems. NFPA 13 is the referenced standard identifying how sprinklers are to be installed, maintained, and inspected but NFPA 13 is not a scoping standard for sprinklers.

sean

1/11/2022 04:26:23 pm

NFPA 13R additionally can only be used if the area increase for sprinklers has not been used.

Glenn Berger

1/10/2022 08:36:09 am

Double check the area of the bathrooms with respect to face of finished walls. If still greater than 55 feet, then sprinklers are required.

Matthew Willis

1/10/2022 08:48:11 am

Also,

Do NOT fall into the scaling trap. Use the Floor Plans to get actual dimensions of the room. Let the math guide you.
If the math leads you to over 55, then sprinklers are required.
As others have stated, our codes and standards represent the MINIMUM requirements to apply.

How would defending this sound in a court of law when the wording is very clear....

R/
Matt

Joe F.

1/10/2022 10:45:15 am

I agree with Wes above, don't cut it so close. Even if the bathrooms are designed as 55 sq. ft. when the bathrooms are physically framed it is inevitable that some of the bathrooms grow in size in inch or two due to framing errors, and you will end up with an unsprinklered bathroom that is >55 Sq. Ft. There needs to be room for error. Arch should design the bathrooms to 54 Sq. Ft. or less if they want to eleminate sprinklers.

1/10/2022 12:30:29 pm

For all of those stating to follow the letter of the code (which I do as well), the requirement is for bathrooms inside dwelling units exceeding or greater than 55 sf.

sean

1/10/2022 01:34:31 pm

I don't know your role or the role of the other individuals but this is a good time to document it.

Lets day you are the PM or Foreman and the designer is saying it will be fine, when the inspector gets out on site and says hey these are more than 55sq.ft. what will happen then.

I would also say while the AHJ could agree to do anything the contractor would still be liable for the design, saying the fire marshal let me is not a great defense

Jack G

1/10/2022 03:56:39 pm

Be careful. There is always a note on all architectural set if drawings , that the dimensions are within 1,5 inches and can vary.
I ran into that in a hotel, when I field checked the floors, prior to installation to verify the partition locations, the bath rooms were an inch or so larger each direction which put them about .36 over the 55 sq. Ft.
Owner was ticked adding 144 heads in bathrooms. CM was ticked. Carpenters were the culprit. But followed the plan.
Always field check. Always field check the spaces subject to “ not requiring sprinklers >”
After 57 years, not many surprises to me.

Jon N

1/10/2022 08:24:55 pm

I have read the previous posts and I must admit that, as an AHJ, I am torn on this. Yes; 55 ft. is 55 ft. but don't forget that the administrative chapters of virtually every code requires "reasonable" enforcement or states that the code is intended to provide a reasonable level of fire (or life) safety.

I have been blessed to have been on several code committees over the years and have seen first-hand where sometimes these code thresholds are "committee numbers". They are not based on any science (i.e. it is impossible for a 55 sq. ft. room to have a fire - NOT!). It was probably an arbitrary number that someone calculated was necessary based on a reasonably-sized space to accommodate typical bathroom needs (sink, tub, toilet, cabinets, etc.).

I teach beginner fire code officials to measure things with a tape measure or ruler, not a micrometer. Exactly how do you measure a space - do you measure it at the floor? Do you measure it at waist level? Do you measure it at the ceiling? Most people seem to measure it based on floor area. My guess is that the room size varies based on whether it is measured at the floor or at the ceiling (a perfectly straight vertical wood stud wall seems very rare nowadays). If the measurement is taken at the floor (floor area), a simple solution is to install "quarter-round" trim around the inside of all of the walls.

Whew; by installing quarter-round trim you just made things so much safer from fire (that was intended as a cynical remark and to add a bit of humor).

As an AHJ if this were brought to my attention, would I question it? YES. Would I have found it on my own during plan review or inspection? PROBABLY NOT. If I were aware of it, would I ask the architect or general contractor how they intend to address it? YES. Would I lay awake nights worrying about it like I do over the dozens of egress violations and egregious sources of ignition that we see every day? NO!

Jessica Lutz

1/11/2022 10:19:51 am

55 sqft is the limit...period.

Construction tolerances always need to be considered.

Never design to the exact threshold...always give yourself a safety factor, a cushion, or a way out when slight changes happen during actual installation.

Munny Khan

1/11/2022 01:20:23 pm

I would definitely err on the side of caution and add a head anyways.

It sounds like a philosophical/mathematical questions, what is greater than 55? 56. What is greater than 55.0? 55.1. Maybe that should be clarified?

I also like the reference to the metric equivalent. Begs the question: From which is the value derived?

Chris Hall

1/11/2022 02:46:33 pm

I pulled the SQFT from an enlarged bathroom plan with dimensions. I feel like they should be sprinkled as I interpret it as 55.00sqft, but at this point I feel like it is really splitting hairs. I told our other designer to proceed with heads in the bathroom unless the architect/owner can come back and tell us that the bathrooms will all be under 55sqft. I know for a fact there are some hotels in this area that have bathrooms over 55sqft that aren't sprinkled. But I had nothing to do with them, and skirting code isn't for me. In a way to add to the "splitting hairs" when we pull the sqft with Autosprink on the CAD drawings it shows it as 55sqft.

Jay

1/11/2022 04:28:37 pm

NFPA 13 speaks to not using a level of precision greater than intended.

NFPA 72 elaborates on this and says
1.6.5 *
The values presented for measurements in this Code are expressed with a degree of precision appropriate for practical application and enforcement. It is not intended that the application or enforcement of these values be more precise than the precision expressed.

A.1.6.5
Where dimensions are expressed in inches, it is intended that the precision of the measurement be 1 in., thus plus or minus 1∕ 2 in. The conversion and presentation of dimensions in millimeters would then have a precision of 25 mm, thus plus or minus 13 mm.

Anonymoose

1/11/2022 06:41:15 pm

55 SF = 2 significant digits
5.1 SM = 2 significant digits

55.4 SF = 3 significant digits

Your reference to 5.1 threshold actually implies that going beyond 2 significant digits is not the intent of the standard.

That being said, getting the architect to put their name on the 55 SF number is always good for your future liability.

Eric Young

1/12/2022 11:17:38 am

Let's say a fitter installs sprinklers 10 feet apart. Going back, we measure and find one head is actually 10.042 feet from the next. The pipe was not screwed in as far as the others. Is it over-spaced? Well, yes! Time to re-cut that pipe? No.
I believe we round off to the nearest value using the significant digits of the value given; in this case the nearest square foot. 55.4 rounds down to 55, not up to 56. If NFPA gave 7920 square inches as the limit, your 55.4 square feet becomes 7977.6 square inches, which rounds to 7978 square inches- that would be over the limit by 58 square inches, so it is fortunate NFPA set the limit using square feet.
Unfortunately, NFPA is a bit grey on the topic except where they talk about SI conversions- maybe there is some insight to be gained by studying that.

Chris Hall

1/12/2022 09:04:00 pm

And those are good points, and part of why I sent the question in. The significant number comment intrigued me because that’s a good point, and made me think about how the .4sqft overage technically would round down if you are going off of the figure as a whole number.

sean

1/12/2022 09:50:44 pm

while eric's thought experiment is nice, I don't think it holds up.

many measurements in nfpa 13 are expressed as a minimum of X, or a maximum of X, not less than X, etc.

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Allow Omission for 55.4 sqft Bathrooms?

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