• Welcome to the new and improved Building Code Forum. We appreciate you being here and hope that you are getting the information that you need concerning all codes of the building trades. This is a free forum to the public due to the generosity of the Sawhorses, Corporate Supporters and Supporters who have upgraded their accounts. If you would like to have improved access to the forum please upgrade to Sawhorse by first logging in then clicking here: Upgrades

Most cost-effective fire wall?

Typically metal building columns are not exterior, nor are they within the exterior wall.
 
Ok, I still lose. I got a technical interpretation from ICC and they agree with the city. The steel framing that is located at the exterior is "within" the wall according to ICC and would need 2hr protection if I choose to use a IIIB construction type for the building. The adviser who called agreed that the verbiage is unclear and pointed out that the wording in the 2000 edition where 713.5 reads "structural members located in exterior walls or along the outer lines of a buillding or structure shall be protected as required by Table 601 for exterior load-bearing walls based on the type of construction." He said it was "clarified" in the 2003 edition.
 
DwightB said:
Ok, I still lose. I got a technical interpretation from ICC and they agree with the city. The steel framing that is located at the exterior is "within" the wall according to ICC and would need 2hr protection if I choose to use a IIIB construction type for the building. The adviser who called agreed that the verbiage is unclear and pointed out that the wording in the 2000 edition where 713.5 reads "structural members located in exterior walls or along the outer lines of a buillding or structure shall be protected as required by Table 601 for exterior load-bearing walls based on the type of construction." He said it was "clarified" in the 2003 edition.
Click to expand...
I'm sorry, but that's not consistent with Table 601 footnotes a and g and that is what governs exterior walls per 704.5. You have a structural frame.

You have an exterior, non-load bearing wall.

You have more than 30' from the property lines.

Where does two hours come from?
 
The wall has to be constructed of metal or wood studs or masonry to be a load bearing wall.

ICC and the BO are wrong

Table 601

Nonbearing walls and partitions Exterior See Table 602

WALL, LOAD-BEARING. Any wall meeting either of the following classifications:

1. Any metal or wood stud wall that supports more than 100 pounds per linear foot (1459 N/m) of vertical load in addition to its own weight.

2. Any masonry or concrete wall that supports more than 200 pounds per linear foot (2919 N/m) of vertical load in addition to its own weight.
 
According to the answer man, the 2 hours is right there in Table 601 under Type IIIB construction, Bearing Walls, Exterior: 2

The fact that footnote a excludes the columns, girders, etc carried no weight.

His primary argument was from 714.5, "Load-bearing structural members located within exterior walls or on the outside of a building or structure shall be determined in accordance the highest fire-resistance rating as determined in accordance with the following:

1. Table 601 for the element according to construction type. (Exterior wall, IIIB - 2 hr)

2. Table 601 for exterior bearing walls based upon construction type. (Exterior wall, IIIB - 2 hr)

2. Table 602 for exterior walls based upon fire separation distance (30' clear - 0 hr)

He basically agreed that the "within the exterior wall" part of the definition was a poor choice of words and pointed to the 2000 edition where it was more clearly stated as "Structural members located in exterior walls or along the outer lines of a building or structure shall be protected as required by Table 601 for exterior bearing walls based on the type of construction."

Using that wording, it's hard to say that the steel main frame members at the purlin line of the exterior wall is not included in the requirement to be rated as according to bearing walls, again a 2 hr requirement.

So, brudgers, yes there is a structural frame and because it is along the exterior wall, must be rated as for an exterior bearing wall. Whether bearing or non-bearing and 30' or more separation is not a mitigating factor.

So, mtlogcabin, bearing/non-bearing walls, not a factor. The frame must be rated 2hr because it is structure that is "within" (or more clearly in 2000 IBC, "along the outer lines of the building") the outer wall.

As such, I cannot go with IIIB construction and will go with VB and use a firewall to break it down to legal portions.
 
By that definition of "within exterior walls," the two hour rating would apply to all interior columns.

And all exterior walls would be load bearing.

The intent of 714.5 is that when you have a load bearing wall, you cannot interrupt the fire rating for a column, or floor joist.

Furthermore the fact that it has changed, indicates that the language in the 2000 edition was not the intent of the section.

Even if the reviewer wishes it was.

Tl;dr = it's not a bearing wall.
 
So, I'm back to needing an inexpensive firewall to separate buildings. Owner is balking at 8" block ($13K) and suggesting steel studs laid out horizontally, install rock and tape 2 layers and tilt up in sections, then rock and tape exposed side (that's what I was considering 2 wks ago). Bldg Mfr is checking to see about just installing the 2 layers on the skin of the existing (how can I possibly tape the "face" of the finished wall on the existing side if it's screwed to an existing building?). Then add steel studs and 2 more layers of rock. It seems that a fire on the existing would pull the existing side of rock down and then I would lose the fire wall.

Am I re-inventing a wheel? How do others firewall between old and new metal buildings?
 
DwightB said:
Am I re-inventing a wheel? How do others firewall between old and new metal buildings?
Click to expand...
By making it go away through proper interpretation of the current building code rather than applying some half-assed interpretation of the 2000 version.

Otherwise, area separation wall.
 
Well Dwight - I certainly hope you have been adequately straightend out. The omnipotent one has spoken.
 
syarn said:
704.10 exterior structural members might be it....the structure is load bearing & therefore needs to be 2 hour protected...in IIIB...
Click to expand...
Read the definition of "Wall, Load Bearing."

It's on page 21 of IBC 2009.

It's on page 20 of IBC 2006.

It's on page 269 of IBC 2003.
 
ok.

hmm...the way I read 704.10 is "load-bearing structural members" (not a wall) have to be provided with a fire-resisance rating as determined by the three following:

1. the construction type IIIB - rating as primary structure 0 hours.

2. construction type IIIB -rating AS A EXTERIOR BEARING WALL (so not that a bearing wall exists BUT that the load bearing structure is) - 2 hours.

3. exterior walls based on separation > 30 feet - 0 hours.
 
The secondary members of a PEMB (e.g. the girts) can reasonably be said to be within the wall.

It's asinine to claim that the bents are.
 
Beating a dead horse, will go with 2 hr fire wall. Owner has chosen wood framing, built horizontally in sections with 2 layers of x-ratedtop gyp on the surface, then the builder insists he can tilt them into position, fire caulk and attach together and to the existing building with alum screws, then 2 layers of x on the new face and finish the new building.
 
Two comments:

1. Isn't this the guy who built without a permit?

2. With the Owner designing it, at least you won't be sealing it.
 
Are max. fire areas an issue (also Ch. 7) Block wall can be an effective solution, easily achieving 3 hours with the right opening protectives. Did you say sprinklers? (sorry skimming 4 pages of posts - probably missed a good deal)
 
Will be using a GA design for 2x4 stud wall with 2 layers of gyp and insulation. No sprinklers. A 2 hr separation is adequate to allow the existing and new buildings with 30' separation on 3 available sides.
 
You must log in or register to reply here.
Top