Reason Why Townhouses Are Exempt from IBC?

12/28/2022

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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23 Comments

Pete H

12/28/2022 06:50:22 am

The student dwellings have separate paths of egress from each individual unit? They don't have to go to a common hallway for egress?

Frankly, if they managed to do that (which most colleges won't, especially for second floor dormitories or apartments), yeah, it can fit as a townhouse. Just because it's on a campus and students live there doesn't change that. It's residential and the purpose of fire protection is to suppress the fire long enough for evacuation, as a 13D system is designed to do (as a 13d system is still required.)

IRC (2018 ed.) Sec. R313:
R313.1 Townhouse automatic fire sprinkler systems
An automatic residential fire sprinkler system shall be installed in townhouses
Exception: AN automatic residential fire sprinkler system shall not be required where additions or alterations are made to existing townhouses that do not have an automatic residential fire sprinkler system installed.
R313.1.1 Design and Installation
Automatic residential fire sprinkler systems for townhouses shall be designed and installed in accordance with P2904 or NFPA 13D.

(This also applies to one and two-family dwellings)

Aaron Easter

12/28/2022 12:16:50 pm

Yes, all of these townhouses are getting 13D systems. I guess I am just wondering why the one down the street is an R2 and installing a 13R system.
If the only difference is a higher degree of separation and separate utilities (some, not all), why are would a contractor/designer choose to have a more expensive suppression system installed?

12/28/2022 01:52:55 pm

....ans yes, it meets all the ICC requirments for Townhouse and is NOT on campus or owned by the campus. The intent of the structure is 100% for student use.

Todd E Wyatt

12/28/2022 08:16:25 am

This "exception" simply points us to the International Residential Code (IRC) for Code compliance ... it does not eleviate the Code requirements for this building type IF it meets all of the requirements (e.g. 3 stories or less above grade plane, separate Means of Egress) and it meets the definition of "townhouse" (A single-family dwelling unit constructed in a group of three or more attached units in which each unit extends from the foundation to roof and with open space on at least two sides.) and "dwelling unit" (A single unit providing complete, independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking and sanitation).

12/28/2022 12:24:59 pm

Correct. It seems like there are systems ran off domestic water pressure (13D) that really should have the R2 label. When I imagine a townhouse, I see attached structures (3 or more) that are able to be sold individually. The code does not require that! All of these dwellings can be on the same lot. In all fairness, I do view a duplex as residential. 3 story buildings with each dwelling being 3 stories high just “seems” to be in a different category. By code, I it isn’t. Maybe the answer is just to accept it.

In addition to those IRC requirements you mentioned, there are also some separation differences and some utility hook-up restrictions.

Darin Golden

12/29/2022 08:53:36 am

The answer for an AHJ is to always accept the adopted regulations whether you agree with them or not. Don’t fall into the trap of what you think it should say or should require. Code is developed through a consensus process that is highly debated and yes, at times politicized. If you think it should say something different, get on a committee and convince your peers and/or submit proposals.

Jay

12/28/2022 08:46:49 am

I would look at the use rather than only the construction features. Like when a structure was originally constructed and occupied as a single family home (governed by IRC) but has now been rezoned and is used as a dentist office or mercantile, which causes the structure to be governed by the IBC, even though it still looks like a one-family dwelling. Unfortunately the IRC doesn't define single family or even one-family dwelling. But I would refer to the definition of dormitory in IBC "....for persons not members of same family..."
See NFPA 101 definition of one-family dwelling and application in occupancy chapter, "....occupied by members of a single family with not more than 3 outsiders..."
I would also refer to local and state zoning/regulations regarding whether or not people occupying a one-family dwelling need to be related by blood, marriage, or adoption.

12/28/2022 12:31:14 pm

I agree with you here….BUT. This means I as a reviewer would be researching and questioning things that are outside of my scope:
Who exactly will live here after the building is CO’d? I know they will be students.
Are you renting the rooms or the entire unit?

There is nothing in code to stand on. They meet all townhouse requirements, though these buildings will not be “single family”. They will most likely rent rooms individually.

Paul Pinigis

12/28/2022 09:13:03 am

Townhouses are exempt from the IBC simply because they fall under the purview of the IRC. You argue that this is student housing, but Is student housing somehow not residential? If these dwellings are built as townhouses, and used for residential purposes, how is conformance with the IRC less than adequate in your view?

12/28/2022 12:40:48 pm

That is the same thing the Building Official has said in our conversations.

1. Allowing them to install a 13D vs 13R knowing that the unit will likely not have a “single family” occupying the sleeping units. Maybe I am overreacting.

2. The 3 story structures protected by 13D systems with one supply from the main and no FDC to oust pressure, makes me feel uneasy.

Maybe I am overreacting. It does meet the code’s description of a townhouse, I just feel that ICC allows for a bit too much flex. I wondered if I was missing something that could use to label these as requiring what I feel is needed: 13R.

Why would anyone who designs these types of buildings use the R2 design? It would be more expensive and restrictive correct? The only thing they gain is the ability to connect some (not all are required separate in a townhouse) utilities. Right?

12/29/2022 08:48:34 am

1. There’s not much difference between a 13D and 13R system when installed in Group R3 Townhomes and Group R2 Apartments/Condos. Both have similar size compartments so the up to 4 head calc in a 13R usually maxes at a 1-2head calc on the second or third floor making it the same as what a 13D would be called at. Also, both standard allow a combination feed so their isn’t much, if any cost difference in these types of structures.

2. Townhomes have all utilities separated. You are required to have air gaps in vertical walls between townhomes that no utility can pass through. The only exception is electrical from the same unit to feed along the wall for outlets. This exception is not a thru and thru penetration. Having separate utilities is not a cost saving measure. For this reason, most builders design Group R-2 buildings where units only share vertical walls and then market them as Townhomes but they are not true townhomes per IRC. Group R-3 townhomes are generally built as such so builder can sell them for a higher value than condos and the owner owns all the utilities and their maintenance.

Your building official may be allowing amid of IBC and IRC provisions which is why it’s appealing to the builder. I’ve had this happen a few times and when confronted with IRC code provisions, builders quickly change to Group R-2. We do have surrounding jurisdictions that classify these occupancies wrong and knowingly or unknowingly allow the selecting of cost saving combination of code provisions.

sean

12/31/2022 08:41:51 pm

single family is not an occupancy type.

townhomes vs an apartment building are completely different designs. apartments typically will allow for higher density

1/4/2023 08:24:05 am

Thanks for the info Darin. That gives me some peace of mind. It just seems odd that on campus it’s an R2 no matter, but across the street off campus, builder can decide. It does meet code though!

Sean, “single family” is in the definition of a townhouse. I know they are designed differently. The concern was allowing them to design to IRC vs IBC.

Jesse

12/28/2022 10:09:37 am

I'm afraid I don't see the issue here. Would it not be residential??

12/28/2022 12:42:30 pm

It is but there are things they avoid in taking the townhouse exception.
(See my responses to others input)
Maybe I am overreacting.

Will Warlick

12/28/2022 10:29:20 am

Dormitories built under the IRC seems wrong. The code recognizes a higher hazard specific to dormitories. See 2018 IBC 420.10 (dormitory cooking facilities) for example. The code assigns a specific occupancy group classifications to dormitories: R-2 or R-3. It also defines dormitories, and provides other specific requirements for this use (see 2018 IBC 806.2 and Table 1004.5, and IFC 308.4.1, 403.10.2.3, 805.4, 807.2, 807.5.6, 808.2, 904.13 and 906.1, and IPC Table 403.1).
Note that the definition of dormitory distinguishes it from a single-family dwelling. So, if you carefully follow IBC 101.2 and the definition of townhouse, the townhouse-style buildings used as dormitories might still need to be regulated under the IBC. They are not a “single-family dwelling unit.”
A problem with the relying on this definition is that a building could fall into a grey area: if a college owns and builds the residential building, it would be pretty clear that it is a dormitory. (The code actually makes this distinction in IBC 1107.4#4: “dormitory housing provided by places of education.”) But if a private investor builds it, they could claim its use will be as single-family dwellings. Is there a provision in the code for ongoing regulation of who rents the townhouses?
Unfortunately, the code is vague, and I agree that it doesn’t feel right to have dormitories built as IRC townhouses.

12/28/2022 12:50:34 pm

This is EXACTLY what I am trying to convey to my building official. These are all private investors and they will almost surely rent by room not unit.

I was hoping that I was missing something that I could stand on to deny a townhouse exception, but I cannot ask for specifics on their intent!: “this is for single family use only right?”

Maybe I am overreacting and the 13D system will protect these 3 story water main pressure supplied systems? I sure would like to see FDC possibilities on these structures.

Chad

12/28/2022 01:35:56 pm

That not a life safety issue... on paper. We cannot out regulate greed in the name of safety because the politicians will not allow it.

You are in a losing battle. Can you stand up an inspections program that has you inspecting all rentals every 1, 2 or 3 years? You can find that they are deadbolting individual bedrooms and make a case they are a problem that way and fight against slum lords that way. But again, perhaps, the politicians will not allow that either.

12/31/2022 08:38:45 pm

how they rent them has no bearing on the code.

the IBC only has a req. for dorms when it is built like an R2 and owned but the high education institute.

what is your role?

1/4/2023 08:18:57 am

That is a bit of my issue. The college would be required to label these R2, but off campus used in the exact manner gets the townhouse exemption. I was happy to read Darin Holden’s response to another thread above. 13D and 13R capabilities are similar.

I am the Fire Planning Officer and commercial inspector. Inspect what I review. New to profession. 8 months off the truck.

Patrick Drumm

1/26/2023 10:02:33 am

I don't think it is overreacting because these allowances can have implications down the line. Imagine if you lived in Rhode Island. The Building Code allows these townhomes to be treated as Residential. The section below eliminates the requirement for sprinklers in the residential code, but gives the owner the option. Not many owners opt to spend that money...

R313.1 Delete sections R313.1 and 313.2 and substitute the following

"R313.1 General.
Automatic fire sprinkler if installed at the applicant’s option will be in conformance with Appendix RP"

Appendix RP is a Rhode Island modified allowance for NFPA 13D system.

Robert Hughes

12/28/2022 02:03:36 pm

Safety is no longer first.
It is the Almighty Dollar, first and foremost.
Even NFPA has more stringent protection for property than for life.

Joshua Perez

8/30/2023 12:51:18 pm

If this is a sprinkler issue - let's remember there are plenty of jurisdictions that have stripped the requirement of an automatic suppression system from their adopted version of the IRC. Kentucky for example, does not require suppression in single or two family residential occupancies.

Run with the 13D.

Reason Why Townhouses Are Exempt from IBC?

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