Building Code and Building Construction - Questions and Answers
Or when you want to know how construction is supposed to be done.

|
AskCodeMan.com
|

Custom Search

Fire sep. in townhouse

Fire sep. in townhouse

New postby Marc M on Wed Nov 04, 2015 2:26 pm

Hey Jerry, I'm sitting for the CA J1 ICC test which is based on the 2013 CRC which was recently added, which is to say there are no study materials for this test yet. That said, I've been studying the 2015 IRC ( based on what the ICC staff suggested) but honestly, I thing the 2012 is a better choice.. your opinion..

So my question is based on the 2013 tables 302.1(1) and 302.1(2) the fire separation between townhouses with and without fire suppression is both 1 hour?
The 2015 has it at 2 w & 1 w/o fire sprinklers..

The 2012 IRC has the exact same charts..

Then there are two family dwellings which I can clearly see as a 2 and 1 hour sep..

So am I confused because of the terms two family dwelling vs. townhouse?
Am I correct that the fire sep with and without fire sprinklers are both 1 hour?
Im just stuck and dont feel I can move fwd without figuring this out.. thanks
Pics are all backwards..bottom to top
let me know if you need any more images
You do not have the required permissions to view the files attached to this post.
Marc M
 
Posts: 173
Joined: Sat May 09, 2009 10:24 am

Re: Fire sep. in townhouse

New postby Jerry Peck - Codeman on Wed Nov 04, 2015 9:03 pm

Marc,

First, a clarification, then a partial answer (need clarification for additional answers).



Marc M wrote:So my question is based on the 2013 tables 302.1(1) and 302.1(2) the fire separation between townhouses with and without fire suppression is both 1 hour?
The 2015 has it at 2 w & 1 w/o fire sprinklers..

The 2012 IRC has the exact same charts..


The clarification: I want to make sure I am reading that correctly - that the tables in the 2012 IRC, 2015 IRC, and 2013 CRC are the same.

So am I confused because of the terms two family dwelling vs. townhouse?


The answer to that part of the question is based on the definitions of a townhouse.

From the IRC 202 Definitions:
- TOWNHOUSE. A single-family dwelling unit constructed in a group of three or more attached units in which each unit extends from foundation to roof and with a yard or public way on at least two sides.

The residential code addresses three types of buildings:
- single-family (detached) (stand-alone dwelling unit)
- two-family (attached) (i.e., 'duplex')
- townhouses (attached) (i.e., '3 or more')

There are also different types of walls for separation of townhouses as the separation wall between townhouses is supposed to be constructed such that the building (each townhouse is a separate "building") on one side of the separation wall should be able to burn down or fall down without affecting the attached townhouses on either/both/one side (depends on how the townhouses are laid out).

Remember the old townhouses where they were 'quads' and each unit had a 'front and a side' but did not 'go all the way through front-to-back'? I have not seen new ones of those built in quite some time as most people want 'front and back' instead of a 'front and a side which opened up to 'one area'. Let's say one is outside grilling and the grill gets out of hand and blazing ... and the structure catches on fire - there is no other way out than past that blazing, burning area. Those meet the "with a yard or public way on at least two sides" part of the definition of a "townhouse" in the strictest sense.
Jerry Peck - CodeMan
AskCodeMan.com
Construction Litigation Consultant - Retired
Construction and Code Consultant - Semi Retired
User avatar
Jerry Peck - Codeman
Site Admin
 
Posts: 1199
Joined: Fri Dec 12, 2008 12:06 pm

Re: Fire sep. in townhouse

New postby Marc M on Wed Nov 04, 2015 11:02 pm

Hey jerry thanks for the help..

So yes, all three code books show the same table. What got this started was when i read a flash card and it said that the non sprinklered home is 2 hr and the sprinkler home is 1 hour. So i went looking for that so i could read it myself and cannot find that language...perhaps you can?

Got the townhouse def. I wasn't sure if they were suggesting that they were one in the same because its CLEARELY written that a 2 family dwelling is 1 hr with sprinklers and .5 hr w/o.Although its still not 2 & 1.      

R302.3 Two-family dwellings.
Dwelling units in two-family dwellings shall be separated from each other by wall and/or floor assemblies having not less than a 1-hour fire-resistance rating when tested in accordance with ASTM E 119 or UL 263. Fire-resistance-rated floor-ceiling and wall assemblies shall extend to and be tight against the exterior wall, and wall assemblies shall extend from the foundation to the underside of the roof sheathing.

Exceptions:

1. A fire-resistance rating of 1/2 hour shall be permitted in buildings equipped throughout with an automatic sprinkler system installed in accordance with NFPA 13.
You do not have the required permissions to view the files attached to this post.
Marc M
 
Posts: 173
Joined: Sat May 09, 2009 10:24 am

Re: Fire sep. in townhouse

New postby Marc M on Wed Nov 04, 2015 11:52 pm

Just found this in 2015...
I wonder how come there are different numbers in the table?
You do not have the required permissions to view the files attached to this post.
Marc M
 
Posts: 173
Joined: Sat May 09, 2009 10:24 am

Re: Fire sep. in townhouse

New postby Jerry Peck - Codeman on Thu Nov 05, 2015 11:04 am

Marc,

That flash card you showed - is that the front and back of the same card?

If it is ... you have your work cut out for you to decipher what ICC is asking - the question is asking about "In a nonsprinklered townhouse" and the answer on the back answers about "where the building is sprinklered" ... might as well ask 'what color are apples' and the answer is 'oranges are orange'.

I have attached two sections from the 2013 CRC, one for townhouse separation and one for two-family dwelling separation. Note that townhouses are defined as "in which each unit extends from foundation to roof" and two-family dwellings are not required to extend from foundation to roof because two-family dwellings may be separated by "by wall and/or floor assemblies".

Townhouse separation is required to be fire-resistance-rated wall assemblies meeting the requirements of Section R302.1 for exterior walls, and that R302.1 references Table R302.1(1) for nonsprinklered andTable R302.1(2) for sprinklered.

The requirements are confusing until what is says is understood - and re-understood each time I forgot what it says after reading them again - but this is what it says:

(From the 2012 IRC (because I can copy and paste from it) (underlining is mine)
- R302.2 Townhouses.
- - Each townhouse shall be considered a separate building and shall be separated by fire-resistance-rated wall assemblies meeting the requirements of Section R302.1 for exterior walls.

R302.2 refers us to R302.1
- R302.1 Exterior walls.
- - Construction, projections, openings and penetrations of exterior walls of dwellings and accessory buildings shall comply with Table R302.1(1); or dwellings equipped throughout with an automatic sprinkler system installed in accordance with Section P2904 shall comply with Table R302.1(2).

- - - TABLE R302.1(1) EXTERIOR WALLS
- - - - <5 feet separation requires 1 hour fire-resistance rating for each townhouse
- - - TABLE R302.1(2) EXTERIOR WALLS—DWELLINGS WITH FIRE SPRINKLERS
- - - - 1 hour fire-resistance rating for each townhouse permits -0- feet separation

- - - (Note that the two tables are saying the same thing - that each (key word from R302.2)) townhouse shall have minimum 1 hour separation from any other townhouse.)

Now let's go back to R302.2 Townhouses and the exception:
- R302.2 Townhouses
- - Exception: A common 1-hour fire-resistance-rated wall assembly tested in accordance with ASTM E 119 or UL 263 is permitted for townhouses if such walls do not contain plumbing or mechanical equipment, ducts or vents in the cavity of the common wall. The wall shall be rated for fire exposure from both sides and shall extend to and be tight against exterior walls and the underside of the roof sheathing. Electrical installations shall be installed in accordance with Chapters 34 through 43. Penetrations of electrical outlet boxes shall be in accordance with Section R302.4.

THIS says that EACH townhouse shall have a 1-hour fire-resistance rated wall:
- R302.2 Townhouses.
- - Each townhouse shall be considered a separate building and shall be separated by fire-resistance-rated wall assemblies meeting the requirements of Section R302.1 for exterior walls.

THIS says that the wall can be a COMMON 1-hour fire-resistance-rated wall ... provided the requirements in the exception are met:
- - Exception: A common 1-hour fire-resistance-rated wall assembly tested in accordance with ASTM E 119 or UL 263 is permitted for townhouses if such walls do not contain plumbing or mechanical equipment, ducts or vents in the cavity of the common wall. The wall shall be rated for fire exposure from both sides and shall extend to and be tight against exterior walls and the underside of the roof sheathing. Electrical installations shall be installed in accordance with Chapters 34 through 43. Penetrations of electrical outlet boxes shall be in accordance with Section R302.4.

Thus, each side of the common 1-hour fire-resistance-rated wall would have no penetrations except those which meet this:

- R302.4.2 Membrane penetrations.
- - Membrane penetrations shall comply with Section R302.4.1. Where walls are required to have a fire-resistance rating, recessed fixtures shall be installed so that the required fire-resistance rating will not be reduced.
- - - Exceptions:
- - - - 1. Membrane penetrations of maximum 2-hour fire-resistance-rated walls and partitions by steel electrical boxes that do not exceed 16 square inches (0.0103 m2) in area provided the aggregate area of the openings through the membrane does not exceed 100 square inches (0.0645 m2) in any 100 square feet (9.29 m2) of wall area. The annular space between the wall membrane and the box shall not exceed 1/8 inch (3.1 mm). Such boxes on opposite sides of the wall shall be separated by one of the following:
- - - - - 1.1. By a horizontal distance of not less than 24 inches (610 mm) where the wall or partition is constructed with individual noncommunicating stud cavities;
- - - - - 1.2. By a horizontal distance of not less than the depth of the wall cavity when the wall cavity is filled with cellulose loose-fill, rockwool or slag mineral wool insulation;
- - - - - 1.3. By solid fire blocking in accordance with Section R302.11;
- - - - - 1.4. By protecting both boxes with listed putty pads; or
- - - - - 1.5. By other listed materials and methods.
- - - - 2. Membrane penetrations by listed electrical boxes of any materials provided the boxes have been tested for use in fire-resistance-rated assemblies and are installed in accordance with the instructions included in the listing. The annular space between the wall membrane and the box shall not exceed 1/8 inch (3.1 mm) unless listed otherwise. Such boxes on opposite sides of the wall shall be separated by one of the following:
- - - - - 2.1. By the horizontal distance specified in the listing of the electrical boxes;
- - - - - 2.2. By solid fireblocking in accordance with Section R302.11;
- - - - - 2.3. By protecting both boxes with listed putty pads; or
- - - - - 2.4. By other listed materials and methods.
- - - - 3. The annular space created by the penetration of a fire sprinkler provided it is covered by a metal escutcheon plate.
(Note that under exception 2., in 2.3, above for electrical boxes which are any material other than steel (steel boxes are covered in exception 1) that it permits putty pads ... however, finding putty pads which are listed for use with boxes made of material other than steel may be quite difficult, all the putty pads I've seen so far are intended and listed for use with steel electrical boxes - I keep looking for putty pads made for nonmetallic boxes, if you find some, please let me know. I have a newsletter on this issue here: http://jerrypeck.com/IFCN/2014-10%20IFC ... 20IFCN.pdf .)

Another way to think of it is that townhouses require two 1-hour rated walls back-to-back to separate them from each other ... unless there is a common 1-hour rated wall which meets the limitations for the common 1-hour rated wall.

Does the above help with your question? Minimum townhouse fire-resistance rating separation for EACH townhouse is 1 hour, minimum fire-resistance separation for the COMMON wall is 1 hour and the common wall strictly prohibits some things from being in that common wall.

2013 CRC Townhouse Separation.jpg


2013 CRC Two-Family Separation.jpg
You do not have the required permissions to view the files attached to this post.
Jerry Peck - CodeMan
AskCodeMan.com
Construction Litigation Consultant - Retired
Construction and Code Consultant - Semi Retired
User avatar
Jerry Peck - Codeman
Site Admin
 
Posts: 1199
Joined: Fri Dec 12, 2008 12:06 pm

Re: Fire sep. in townhouse

New postby Marc M on Thu Nov 05, 2015 12:20 pm

Wow...what a cluster. I re read that section about a thousand times so now Im pretty sure Im a townhouse expert in fire separation, lol.
Check this out..the newest release of 2015 redefines the separation as with and without fire suppression. Its language now is very very clear and literally states the separation in both circumstances.
Revised as follows:

R302.2 Townhouses. Each townhouse shall be considered a separate building and shall be separated
by fire-resistance rated wall assemblies meeting the requirements of Section R302.1 for exterior walls.
Exceptions:

1. Where a fire sprinkler system in accordance with Section P2904 is provided, a common 1-
hour fire-resistance-rated wall assembly tested in accordance with ASTM E 119 or UL 263 is
permitted for townhouses if such walls do not contain plumbing or mechanical equipment,
ducts or vents in the cavity of the common wall. The wall shall be rated for fire exposure from
both sides and shall extend to and be tight against exterior walls and the underside of the
roof sheathing. Electrical installations shall be installed in accordance with Chapters 34
through 43. Penetrations of electrical outlet boxes shall be in accordance with Section
R302.4.

2. Where a fire sprinkler system in accordance with Section P2904 is not provided, a common
2-hour fire-resistance-rated wall assembly tested in accordance with ASTM E 119 or UL 263
is permitted for townhouses where such walls do not contain plumbing or mechanical
equipment, ducts or vents in the cavity of the common wall. The wall shall be rated for fire
exposure from both sides and shall extend to and be tight against exterior walls and the
underside of the roof sheathing. Electrical installations shall be installed in accordance with
Chapters 34 through 43. Penetrations of electrical outlet boxes shall be in accordance with
Section R302.4.

R302.2.4 Structural independence. Each individual townhouse shall be structurally independent.

Exceptions:

1. Foundations supporting exterior walls or common walls.
2. Structural roof and wall sheathing from each unit may fasten to the common wall framing.
3. Nonstructural wall and roof coverings.
4. Flashing at termination of roof covering over common wall.
5. Townhouses separated by a common (delete: 1-hour fire resistance-rated) wall as provided in Section
R302.2, Exceptions 1 or 2.

Reason: The 1-hour separation requirements in these sections were reduced from 2-hour ratings in prior editions of the IRC based
on the assumption that fire sprinklers mandated by the IRC would be present in all townhouses. Because some jurisdictions are
amending the IRC to remove the fire sprinkler requirement, it is essential that the IRC provide for townhouse separation fire ratings
to be returned to 2-hours if sprinklers are not provided. No justification, other than sprinklers, was ever provided for allowing a 1-
hour separation, and this reduced rating is inappropriate for non-sprinklered buildings.

Cost Impact: The code change proposal will not increase the cost of construction.

Committee Action: Approved as Submitted

Committee Reason: The committee approved this proposed code change because they felt that a) it takes care of an important
omission in the code related to fire sprinkler systems and b) it addresses the many ways in which jurisdictions adopt the code and
modify sprinkler requirements.

Complete Revision History to the 2015 I-Codes: Successful Changes with Public Comments: 2015 IRC
Marc M
 
Posts: 173
Joined: Sat May 09, 2009 10:24 am


Return to Fire-rated assemblies: Fire walls, fire partitions, smoke barriers, ceiling-floor, ceiling-attic; Separation of garages from dwelling unit; Separation between structure's exterior walls and property line



Who is online

Users browsing this forum: No registered users and 2 guests


cron