Individual member encasement 2 hour 6 floors

[milam@tomanbrothers.]

What is by best tool to go up agnaist an Architect wanting to put structural members inside A fire wall asembly and call it good to get A rating ? Table 601 states structural members nato an assembly (fire wall or partition or barrier ....)

2 hour rated structural steel.

Thanks

Milam

 

[TheCommish]

Ask nicely for RDP to provide the UL or equivalent assembly number and data for the proposed assembly

 

[Yankee Chronicler]

Ask nicely for RDP to provide the UL or equivalent assembly number and data for the proposed assembly

^^^ This is a start, but the architect will probably respond with the U.L. design number for the wall assembly. What he/she needs to understand is that a 1-hour wall assembly is rated for 1 hour from one side of the wall to the other side of the wall. it has not been tested for ANY level or time of protection for something located inside the wall. It may (or may not) provide even 1/2-hour for something inside the wall. We can't know, because wall assembles are tested as walls -- from one side to the other side.

The U.L. design book (I still think of it as a red book, but I know it's all on-line today) has completely separate series of assemblies for protecting columns. If the structure requires 1-hour protection, the columns must be protected with an assembly found in the U.L. designs for columns.

 

[Yankee Chronicler]

Here's an example, from the USG fireproofing manual - UL Design X528:

 

[TheCommish]

My goal when asking RDP to proved a listed assembly is for the RDP to do the research which is their responsibility, and during that research the RDP will either realize the improper application of the drawn assembly, narrow down the assembly options to the one that is to be used (for example UL 341 has numerous configurations for insulation, sheathing and sheetrock on various surface of the double wall design) see the UL deign for what is shown and not applicable, thereby selecting the correct design, before I have to tell the RDP the picture doe not match what is allowed.

 

[Yankee Chronicler]

"UL 341"? I think you're missing a letter in there.

I agree with trying to teach the architect to do his/her homework, but if an architect believes that putting an unprotected column inside a rated wall means the column is protected to the same level of the wall rating -- I think what you're going to get is a listing of 1-hour or 2-hour U.L. rated wall assemblies.

By all means, proceed according to the plan, and let us know what the architect comes back with.

 

[milam@tomanbrothers.]

x528 is individual encasement correct, not A wall Assembly.

 

[TheCommish]

"UL 341"? I think you're missing a letter in there.

I agree with trying to teach the architect to do his/her homework, but if an architect believes that putting an unprotected column inside a rated wall means the column is protected to the same level of the wall rating -- I think what you're going to get is a listing of 1-hour or 2-hour U.L. rated wall assemblies.

By all means, proceed according to the plan, and let us know what the architect comes back with.

You are correct the example wall assembly would be U341.
I am not the OP, they seemed to have dropped out.

Yankee Chronicler, discuss if a column was to located in a wall, would the column have to be surrounded by its rated assembly with the wall assemble butting to it.

My thoughts, possibly, since a wall could be designed as semetrical (now I am curious are there single direction wall assemblies) Humm, goes of to ponder the discussion.

 

[Yankee Chronicler]

x528 is individual encasement correct, not A wall Assembly.

Yes, it is. That's why I posted it -- you asked how to approach an architect who doesn't appear to understand what column protection is. There's an example.

Wall assemblies are not tested for temperature rise within the wall cavity -- they are tested for temperature rise over time from one side to the other side. The test for column protection is a completely different test. Technically, you can't put a column requiring 1-hour protection in the middle of a 4-hpur wall, because the one-sided membrane of the 4-hour wall hasn't been tested to show that the one side (membrane) will protect anything inside that wall for one hour. It may. It probably will. But it hasn't been tested for that, so the only way a building official can approve it is by modification. I wouldn't take on that liability even if I could (which I can't due to my state's laws).

 

[Yankee Chronicler]

Yankee Chronicler, discuss if a column was to located in a wall, would the column have to be surrounded by its rated assembly with the wall assemble butting to it.

Yes, that is exactly what has to happen.

My thoughts, possibly, since a wall could be designed as semetrical (now I am curious are there single direction wall assemblies) Humm, goes of to ponder the discussion.

I have no idea what you mean by a semetrical or single direction wall system. It isn't a matter of construction -- it's a matter of testing. Walls are tested as walls, they are not tested as column protection. That's why the wall assemblies are in the 'U' series of U.L/ designs, and column protection assemblies are in the 'X' section.

 

[steveray]

Do they not understand the definition of "individual encasement"?

704.2 Column Protection​

Assembly
Where columns are required to have protection to achieve a fire-resistance rating, the entire column shall be provided individual encasement protection by protecting it on all sides for the full column height, including connections to other structural members, with materials having the required fire-resistance rating. Where the column extends through a ceiling, the encasement protection shall be continuous from the top of the foundation or floor/ceiling assembly below through the ceiling space to the top of the column.
Exception: Columns that meet the limitations of Section 704.4.1.

 

[Yankee Chronicler]

My thoughts, possibly, since a wall could be designed as semetrical (now I am curious are there single direction wall assemblies) Humm, goes of to ponder the discussion.

Does this mean wall assemblies that are rated on only one side? Yes, there are ... but I don't know if they are tested as such. Where exterior walls require a rating but there is sufficient fire separation distance, the code allows the walls to be rated against exposure only from the inside. Is that what you mean by a single direction wall assembly?

 

[ajesaitis]

It's pretty simple to explain when using the UL designs. If it's not listed in the assembly shown then it's not part of the system. UL tests only include what's shown or noted in the assemblies. If it's not there then it's not a valid UL assembly. Plus building steel is a separate category from wall/ceiling/floor assemblies. Assemblies address fire separation whereas steel fireproofing addresses the construction type per IBC and other codes. If the architect doesn't understand this then they have a major problem. This is basic code understanding.