Fire Separation to property line

[Life_learner]

Apologies in advance, I cannot find more info in the IBC commentary.
Has anyone run into this before, with exterior walls adjacent to property lines?
I typically use the IBC Commentary to help figure out these items in the code, but I cannot find any commentary answering this item.
A bunch of staff members have already argued this question back and forth, any help will be greatly appreciated.

A-3 Assembly, a health club workout center, 2,000 sf, Type 5B Construction (CMU walls, wood joist/deck)
The west wall is only 3” from the property line, shown in black with labels.
Reading IBC table 706.4 party walls requires 3-hr, but footnote “a” reduces to 2-hr.
But the north and south walls are within 10’ from the property line, are they required to be 1-hr as per Table 602?
OR is it because the west wall abuts at 90 degrees then the north/south wall is protected by the 2-hr west wall?

Same question about the amount of window/door openings allowed in table 705.8, there are overhead coiling doors within 10’ from property line, do these openings need to be protected or does the west 2-hr protect these openings.
link below- plan shows layout.
Is there somewhere I could read more about these requirements?

ANY help is appreciated, -- thank you for your time.

projman.caldwell-assoc.com/_fle/FLDR-479-395653/CODE Questions Fire Separation.jpg

 

[RLGA]

The east wall is not a party wall or a fire wall--it is an exterior wall with no fire separation distance, so Table 602 requires only a 1-hour exterior wall.

The north and south walls do not factor into the situation at all--fire separation distance is measured perpendicular to the face of the wall to the lot line, centerline of a public way (street, alley, etc.), or an imaginary line between two buildings on the same lot. The fire separation distance for the north and south walls would be measured to one of those three locations to the north and south, respectively--the east lot line is not an issue.

 

[Life_learner]

RLGA,
Thank you for your reply.
Your are correct the wall does not currently separate another building, but the adjacent neighbor could build on the property line at anytime.

This reminds me of a downtown property (zero lot zoning) when your building’s property has an adjacent lot that is empty. Would this required to build the wall like a party because adjacent property owner can construct a new building located next to our wall?

RLGA your insights are appreciated.

 

[RLGA]

A fire wall and a party wall (which is a fire wall on a lot line) are walls shared by the buildings on each side of the wall. In your case, if the owner on the neighboring property constructed a building up to the lot line, they would have to build their own zero-lot-line exterior wall--they could not just build up to your wall and use it as part of their building without your permission. If they did, they would be creating a building with an "exterior opening" less than three feet from a lot line, which is prohibited by the IBC.

You could ask the adjacent lot owner about their plans for construction on their property and possibly agree to build a fire wall/party wall centered on the lot line, which will give you about an extra four inches of interior space. They may be willing to share in the cost of the wall, too.

However, in the absence of such an agreement, you (and your neighbor) can only construct up to the shared lot line and not extend over it.

 

[Life_learner]

RLGA,

Thank you for your time and posts they were very helpful.
Chapter 2 definitions with notes about ‘only 90-degree’ perpendicular measured to property lines was helpful.
I hope you have a great week.