When changing from a SFD to a group E

[Sifu]

Existing SFD is undergoing a C of O to a group E. The proposal is to classify it as a group E. No longer a residence. It is VB, 2018 IEBC. IEBC t1011.6 provides the hazard categories, but the table does not include SFD's. Easy enough to consider the SFD a group R, but I am assuming the table considers the occupancies listed to be IBC classifications and since IBC group R's require sprinklers I am not sure it is valid to say the hazard category of an SFD and a group E is the same level since the SFD is not sprinklered. The issue is the SFD is < 10' from the adjacent property line, and the exterior wall is not rated.

In other words, if this was a sprinklered group R changing to a non-sprinklered group E, the table considers them equal in hazard and no FRR for the exterior wall is required, but since the previous occupancy is not in the table (as an SFD) is the new group E occupancy required to follow IBC t602, which requires 1-hr exterior walls where within 10' of the property line?

 

[steveray]

I don't really think that the IEBC takes into account sprinklers for that purpose....?

 

[Sifu]

It seems the issue for converting an SFD to a "commercial" use has been discussed in this regard before, but I am not in my office and can't access any notes I might have. This seems odd because there is so much of that activity. My first reaction was to call it an R and move on, but then I started questioning that approach. Even if sprinklers are not considered, there is still no mechanism for an IRC regulated structure to convert to an IBC structure in the IEBC as far as I can tell.

Is there any evidence or documentation that the requirements associated with an IBC occupancy were/are not considered when determining hazard equivalency?

 

[walker.t]

but the table does not include SFD's. Easy enough to consider the SFD a group R

I think your single-family residence is considered Group R-3 per 310.4: “Primarily permanent” and “Buildings that do not contain more than two dwelling units.”

 

[steveray]

It seems the issue for converting an SFD to a "commercial" use has been discussed in this regard before, but I am not in my office and can't access any notes I might have. This seems odd because there is so much of that activity. My first reaction was to call it an R and move on, but then I started questioning that approach. Even if sprinklers are not considered, there is still no mechanism for an IRC regulated structure to convert to an IBC structure in the IEBC as far as I can tell.

Is there any evidence or documentation that the requirements associated with an IBC occupancy were/are not considered when determining hazard equivalency?

I think your single-family residence is considered Group R-3 per 310.4: “Primarily permanent” and “Buildings that do not contain more than two dwelling units.”

It's a change from R3 to E.....which is an increase in MOE and H&A hazard, but not exterior wall....

 

[steveray]

BTW....The new E only allows 1 story NS VB......

 

[Sifu]

The previous use had no IBC classification. If we use the definitions of IBC 310.4 it works for me based on the description in 310.4 but in the IBC an R3 would have required sprinklers, which are not provided. I assume codes expect the provisions of existing buildings to have met the requirements for the previous occupancy when they put those tables together, but maybe that is incorrect. If I go R3, then t1011.6 requires no changes to the exterior walls. Without an alternative to R3, then I really have nothing to go on.

Now,

If we do consider it an R3, t1011.5 would consider the change to an E as a more hazardous condition and send us to the IBC. IBC t504.4 would limit the E occupancy to 40' and the area to 9,500sf². Number of stories is not addressed. Do I assume they meant height, area and number of stories because they use the general term "height and area"?

So the E occupants have no more hazard from the adjacent space than it did when it was an R3, even though there are a lot more of them and they are children. But the E occupants now have a greater exposure to hazards from the story above based on the new use. With all the critical thinking the IEBC apparently did here, did they accidentally omit the "number of stories" from 1011.5? My maybe erroneous assumption may have been that the E occupancy is limited to the 1st story, but that number of stories isn't addressed.

 

[steveray]

It had a use R3....it was allowed to comply with the IRC...

[A] 101.2 Scope​

The provisions of this code shall apply to the construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal and demolition of every building or structure or 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 2021 International Residential Code portion of the 2022 Connecticut State Building Code.

310.4 Residential Group R-3
Residential Group R-3 occupancies where the occupants are primarily permanent in nature and not classified as Group R-1, R-2, R-4 or I, including:

• Buildings that do not contain more than two dwelling units, with not more than six lodgers or boarders per dwelling unit

And story "height" is included as it blanketly sends you back to Ch. 5....Not 504.3 or 504.4.....

1011.6.1 Height and Area for Change to a Higher-Hazard Category​

Where a change of occupancy classification is made to a higher-hazard category as shown in Table 1011.6, heights and areas of buildings and structures shall comply with the requirements of Chapter 5 of the International Building Code for the new occupancy classification.

 

[Sifu]

It had a use R3....it was allowed to comply with the IRC...
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 2021 International Residential Code portion of the 2022 Connecticut State Building Code.

And story "height" is included as it blanketly sends you back to Ch. 5....Not 504.3 or 504.4.....

1011.6.1 Height and Area for Change to a Higher-Hazard Category​

Where a change of occupancy classification is made to a higher-hazard category as shown in Table 1011.6, heights and areas of buildings and structures shall comply with the requirements of Chapter 5 of the International Building Code for the new occupancy classification.

Maybe this is a distinction without a difference, but SFD's are not allowed to comply with the IRC, they are required to comply with the IRC. When the sprinkler requirements are amended out of the IRC, they are not amended out of the IBC automatically. Among all the other code requirements between an IRC and IBC dwelling, that is one of the big ones. And I think it is important if we are going to lump them under the same umbrella.

Also, I am just not seeing in the same black and white as you. Both the CT code and the IBC say specifically "heights and areas". The IEBC:
"heights and areas of buildings and structures shall comply
with the requirements of Chapter 5 of the International Building
Code for the new occupancy classification"

The intent may be that stories are included, but they specifically call out heights and areas, but not stories. A comma and the word "stories" were an easy add.

 

[mtlogcabin]

but in the IBC an R3 would have required sprinklers, which are not provided.

Depends on when it was built. You could build 16 unit apartments without sprinklers at one time

 

[Sifu]

Depends on when it was built. You could build 16 unit apartments without sprinklers at one time

I know, and that is an area that hasn't even been approached yet. Since they didn't even bother to reference the IEBC or provide any IEBC pathways or direction I am flying blind. Ongoing problem as can be read in my other rants. It was absolutely permitted as an unsprinklered IRC-SFD, no matter when it was built, because sprinklers have never been required for IRC SFD's in this AHJ. It could have been an approved R3 if built before the IBC required sprinklers...back before the IBC in general, but the IEBC was written with the IBC in mind, so I assume it assumed any R3 was sprinklered and factored that in. But I am often wrong when I make assumptions about other peoples assumptions.

My head hurts again.

 

[walker.t]

The intent may be that stories are included, but they specifically call out heights and areas, but not stories. A comma and the word "stories" were an easy add.

I agree, I’d prefer to see a reference to “stories” as well. With that said, it seems that the intent is likely that “height and area” should be read as “height, number of stories, and area” based on a a statement in the 2018 IBC Illustrated Handbook:

From 2018 IBC Illustrated Handbook section on IBC Section 504.
Tables 504.3 and 504.4 allow greater heights where an automatic fire-sprinkler system is installed throughout the building. [emphasis added]

Notice this doesn’t say “allow greater heights and number of stories,” just “heights” - but both are increased for the use of sprinklers. I know this is just one brief reference but maybe it gives us a clue as to the intent.

Also notice that the title for Section 503 is “General Building Height and Area Limitations” yet the section discusses number of stories. If I had been proofreading that I would have taken my red pen and added “number of stories.”

Building Codes Illustrated by Frank Ching repeatedly uses “building height in feet” and “building height in number of stories” which always bugged me, “story” cannot be a unit of measurement of vertical distance (in other words, a unit of “height”) because there’s no standard story height. I don’t consider Ching to be the final authority on the interpretation of the building code, but these statements in his book seem to align with the statement in the Illustrated Handbook.

It gives me heartburn to see that they didn’t add the word “stories,” it does seem like an easy add.

 

[steveray]

Maybe this is a distinction without a difference, but SFD's are not allowed to comply with the IRC, they are required to comply with the IRC. When the sprinkler requirements are amended out of the IRC, they are not amended out of the IBC automatically. Among all the other code requirements between an IRC and IBC dwelling, that is one of the big ones. And I think it is important if we are going to lump them under the same umbrella.

Also, I am just not seeing in the same black and white as you. Both the CT code and the IBC say specifically "heights and areas". The IEBC:
"heights and areas of buildings and structures shall comply
with the requirements of Chapter 5 of the International Building
Code for the new occupancy classification"

The intent may be that stories are included, but they specifically call out heights and areas, but not stories. A comma and the word "stories" were an easy add.

If you look at the IBC before Towns screw it up...

[A] 101.2 Scope.​

The provisions of this code shall apply to the construction, alteration, relocation, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures.
Exception: Detached one- and two-family dwellings and 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 this code or the International Residential Code.

 

[Yankee Chronicler]

Basic question: It's an existing building -- which IEBC method are they using for code compliance?. Unless your jurisdiction didn't adopt the International Existing Building Code, the place to begin is the IEBC. For starters, the applicant MUST tell you whether they are using the Prescriptive Method, the Work Area Method, or the Performance Method for compliance. The choice of compliance method will dictate some of the chapters that have to be looked at. You then refer to the IBC only when and where the IEBC sends you there.

Chapter 3 applies for all methods, and for a change of occupancy Chapter 10 applies to all methods.

 

[Yankee Chronicler]

Since they didn't even bother to reference the IEBC or provide any IEBC pathways or direction I am flying blind.

IMHO there's no need or reason for you to fly blind. If your jurisdiction has adopted the IEBC, the applicant is required to state which method of code compliance they are following. If they don't even reference the IEBC, they can't be following the code, so just reject the plans and tell them to try again. You are neither required nor allowed to try to get inside the the applicant's or the designer's head and make assumptions regarding what path they're following (or not) through the codes.

 

[Sifu]

Chapter 3 applies for all methods, and for a change of occupancy Chapter 10 applies to all methods.

Agree for ch. 3, but if they choose the prescriptive method then I am not sure. Chapter 5 for prescriptive has it's own section for C of O, so they can use that which kicks "the building" back to the IBC, with an allowance for the BO to show some leniency.

I think, but am not entirely sure, ch. 10 applies to a C of O when using the work area method. The following section seems to say it applies anytime, as you said, but then how do we implement this if they choose prescriptive?

1001.1 Scope. The provisions of this chapter shall apply
where a change of occupancy occurs, as defined in Section
202.

 

[Sifu]

If you look at the IBC before Towns screw it up...

[A] 101.2 Scope.​

The provisions of this code shall apply to the construction, alteration, relocation, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures.
Exception: Detached one- and two-family dwellings and 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 this code or the International Residential Code.

This is the exception in my PDF collection of the 2018 IBC. There is no path to use the IBC. However, I see my pdf is a 1st printing, and I see that in the printed book I have, a 2nd printing, and the pdf commentary it contains the section you pasted. This allowance was added in the 2018 IBC, but after I paid all that money for the complete collection. I should know better, I always tell AHJ's to never buy codes until at least the 2nd printing. (There are several inconsistences between my 2021 IBC first printing and the 2nd printing.)

Exception: Detached one- and two-family dwellings and
multiple single-family dwellings (townhouses) not more
than three stories high with separate means of egress and
their accessory structures shall comply with the International
Residential Code

But, I see it now. I have never seen an SFD designed to comply with the IRC unless they exceed the story height, but you are correct (only remember once or twice that has happened). Since most AHJ's have amended out sprinklers for an IRC designed SFD, this becomes important. If an IBC designed SFD were approved as an R3 it would need to be sprinklered without some exception having been made. This is not the case for the SFD in question, it was not an R3 by design, so the question remains: Do the hazard tables apply if the SFD was not, and can't be what [I think] the table had in mind for an IBC R occupancy?

As many AHJ's are moving now to adopt new codes, I wonder if this should be considered. Should the amendment to not sprinkle an IRC SFD come with a disclaimer that the use of the IEBC could be in question when converting an SFD to an IBC occupancy? I find it difficult to discount the use of sprinklers as unimportant when considering the hazard levels.

 

[Yankee Chronicler]

Now I'm confused. (Nothing new there.)

I thought by SFD you meant Single Family Dwelling. Then you wrote:

I have never seen an SFD designed to comply with the IRC unless they exceed the story height,

Single family dwellings aren't covered by the IBC, so if a single family dwelling isn't covered by the IRC, what code would it be designed under? Or are you using "SFD" to mean something else?

If they are using the Prescriptive Method, Chapter 5 mentions the IBC, but that doesn't mean Chapter 10 doesn't apply. There's nothing in Chapter 10 (the code or the Commentary) to exempt the Prescriptive Method from Chapter 10. Basically, the Prescriptive Method boils down to just using the IBC anyway, so it's sort of a moot point. My experience is that most designers seem to use the Work Area method, but they usually don't say that and they generally have no idea when it changes from Level 1 to Level 2 to Level 3. In the last three years, we have only seen one project that used the Performance Method (the points scale for equivalent safety), and they got that wrong on the first submittal.

 

[Sifu]

Now I'm confused. (Nothing new there.)

I thought by SFD you meant Single Family Dwelling. Then you wrote:



Single family dwellings aren't covered by the IBC, so if a single family dwelling isn't covered by the IRC, what code would it be designed under? Or are you using "SFD" to mean something else?

If they are using the Prescriptive Method, Chapter 5 mentions the IBC, but that doesn't mean Chapter 10 doesn't apply. There's nothing in Chapter 10 (the code or the Commentary) to exempt the Prescriptive Method from Chapter 10. Basically, the Prescriptive Method boils down to just using the IBC anyway, so it's sort of a moot point. My experience is that most designers seem to use the Work Area method, but they usually don't say that and they generally have no idea when it changes from Level 1 to Level 2 to Level 3. In the last three years, we have only seen one project that used the Performance Method (the points scale for equivalent safety), and they got that wrong on the first submittal.

I wrote IRC, but meant the IBC. The only time I have seen a SFD (Single Family Dwelling) designed to the IBC was when the SFD was more stories than permitted by the IRC. That was many years ago, before the exception expressly allowed the use of either code. It was allowed by the CBO. I can't remember if it was sprinklered.

 

[mtlogcabin]

Reject the plans as submitted until they provide the design method they have chosen for the project.
You are wasting your time and causing undo stress for yourself.

By doing this you will be training them, which will help you for any future submittals they may have.

 

[mtlogcabin]

Exception: Detached one- and two-family dwellings and
multiple single-family dwellings (townhouses) not more
than three stories high with separate means of egress and
their accessory structures shall comply with the International
Residential Code

IMHO the exception in the IEBC with regards to when the IRC would be applicable for a change of use is if it is one of the exceptions listed below in the IRC.

R101.2 Scope.
The provisions of this code shall apply to the construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, removal and demolition of detached one- and two-family dwellings and 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.

Exception: The following shall be permitted to be constructed in accordance with this code where provided with a residential fire sprinkler system complying with Section P2904:

1. Live/work units located in townhouses and complying with the requirements of Section 419 of the International Building Code.

2. Owner-occupied lodging houses with five or fewer guestrooms.

3. A care facility with five or fewer persons receiving custodial care within a dwelling unit.

4. A care facility with five or fewer persons receiving medical care within a dwelling unit.

5. A care facility for five or fewer persons receiving care that are within a single-family dwelling.

 

[steveray]

This is the exception in my PDF collection of the 2018 IBC. There is no path to use the IBC. However, I see my pdf is a 1st printing, and I see that in the printed book I have, a 2nd printing, and the pdf commentary it contains the section you pasted. This allowance was added in the 2018 IBC, but after I paid all that money for the complete collection. I should know better, I always tell AHJ's to never buy codes until at least the 2nd printing. (There are several inconsistences between my 2021 IBC first printing and the 2nd printing.)

Exception: Detached one- and two-family dwellings and
multiple single-family dwellings (townhouses) not more
than three stories high with separate means of egress and
their accessory structures shall comply with the International
Residential Code

But, I see it now. I have never seen an SFD designed to comply with the IRC unless they exceed the story height, but you are correct (only remember once or twice that has happened). Since most AHJ's have amended out sprinklers for an IRC designed SFD, this becomes important. If an IBC designed SFD were approved as an R3 it would need to be sprinklered without some exception having been made. This is not the case for the SFD in question, it was not an R3 by design, so the question remains: Do the hazard tables apply if the SFD was not, and can't be what [I think] the table had in mind for an IBC R occupancy?

As many AHJ's are moving now to adopt new codes, I wonder if this should be considered. Should the amendment to not sprinkle an IRC SFD come with a disclaimer that the use of the IEBC could be in question when converting an SFD to an IBC occupancy? I find it difficult to discount the use of sprinklers as unimportant when considering the hazard levels.

1011.2 gets you sprinklers when warranted and also the area table as you are tied to that and it's story and area increases for NS and S.....For a change of occupancy...

And you would at least get sprinklers on the second floor IMO...

[F] 903.2.3 Group E​

An automatic sprinkler system shall be provided for Group E occupancies as follows:

1. Throughout all Group E fire areas greater than 12,000 square feet (1115 m2) in area.
2. The Group E fire area is located on a floor other than a level of exit discharge serving such occupancies.

 

[mtlogcabin]

903.2.3 only applies to new buildings. The IEBC has to send you to Chapter 9 in the IBC before it is applicable.
Chapter 5 leaves it up to the building official to make the call or accept an alternative. How big is this building and what will be the occupant load would be governing factors when using Chapter 5 IMHO.

[F] 903.2 Where required.
Approved automatic sprinkler systems in new buildings and structures shall be provided in the locations described in Sections 903.2.1 through 903.2.12.

 

[steveray]

903.2.3 only applies to new buildings. The IEBC has to send you to Chapter 9 in the IBC before it is applicable.
Chapter 5 leaves it up to the building official to make the call or accept an alternative. How big is this building and what will be the occupant load would be governing factors when using Chapter 5 IMHO.

[F] 903.2 Where required.
Approved automatic sprinkler systems in new buildings and structures shall be provided in the locations described in Sections 903.2.1 through 903.2.12.

Yes....IEBC 1011.2 (and maybe others) gets you back to the IBC
1011.2.1 Fire Sprinkler System
Where a change in occupancy classification occurs or where there is a change of occupancy within a space where there is a different fire protection system threshold requirement in Chapter 9 of the International Building Code that requires an automatic fire sprinkler system to be provided based on the new occupancy in accordance with Chapter 9 of the International Building Code. The installation of the automatic sprinkler system shall be required throughout the building or within the area of the change of occupancy and areas of the building not separated horizontally and vertically from the change of occupancy by one of the following: