Originally Posted By: mboyett This post was automatically imported from our archived forum.
Inspected a quad (4-plex) today, 2 up/2 down, built 1982, no separation wall (fire wall, smoke stop, whatever you want to call it) in attic. Does a 1-4 family unit require a separation wall? The one’s I’ve seen have all been in multi-unit condos and there’s no question regarding those, just a 4 family unit. I didn’t see anything in the 2003 IRC regarding this. Thoughts?
Originally Posted By: mboyett This post was automatically imported from our archived forum.
Thanks…I agree, I’m not gonna call it. Actually the Realtor explained to me that a 1-4 family unit didn’t require it so I felt a little “uninformed” on what should be a simple matter that I should know.
Originally Posted By: mboyett This post was automatically imported from our archived forum.
Bill,
Yep, you’re right, that could be an issue. In my case, the original construction of the property did not provide access to the attic at all. One of the units had installed a new air handler/furnace in the attic and, in doing so, had added a drop down stairway in one of the bedrooms. So, until the other unit adds an attic access then this unit will be somewhat secure.
Originally Posted By: mcyr This post was automatically imported from our archived forum.
You would think in fairness to the saftey of people that builders and designers would atleast specify a 1-hour seperaration between the units from the basement to the attic.
How often is this done unless a code or AHJ forces them to do it?
Codes are complicated, and therefore you should write and report what you see and that should take care of it.
Originally Posted By: mboyett This post was automatically imported from our archived forum.
Marcel,
I certainly don’t disagree. After a little more digging I did find that 2003 IRC R317.1 does require a 1-hour separation wall even on two-family structures. I could have and should have discussed this in more detail in my inspection report and even had the IRC to refer back to if I had needed it. So, the Realtors contention that a separation wall was not needed on less than 4-family structures is wrong and now I know better.
Originally Posted By: tallen This post was automatically imported from our archived forum.
mboyett wrote:
Marcel,
I certainly don't disagree. After a little more digging I did find that 2003 IRC R317.1 does require a 1-hour separation wall even on two-family structures. I could have and should have discussed this in more detail in my inspection report and even had the IRC to refer back to if I had needed it. So, the Realtors contention that a separation wall was not needed on less than 4-family structures is wrong and now I know better.
I have seen older buildings without the fire wall between units, but I remember having to put "firestop" on service wires at the "party wall" I ran through multi unit buildings back in 1987.
Originally Posted By: mboyett This post was automatically imported from our archived forum.
Gotcha…be nice when the new BB is operational, huh? Did you play with it at all earlier today when it was being tested? It’s going to be pretty nice, I think.
Originally Posted By: gbeaumont This post was automatically imported from our archived forum.
Quote:
317.1 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 1-hour fire-resistance rating when tested in accordance with ASTM E 119. Fire resistance-rated floor-ceiling and wall assemblies shall extend to and be tight against the exterior wall, and wall assemblies shall extend to the underside of the roof sheathing.
Exception: 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.
317.1.1 Supporting construction.
When floor assemblies are required to be fire-resistance-rated by Section R317.1, the supporting construction of such assemblies shall have an equal or greater fire-resistive rating.
317.2 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 for exterior walls.
Exception: A common 2-hour fire-resistance-rated wall is permitted for townhouses if such walls do not contain plumbing or mechanical equipment, ducts or vents in the cavity of the common wall. Electrical installations shall be installed in accordance with Chapters 33 through 42. Penetrations of electrical outlet boxes shall be in accordance with Section R317.3.
317.2.1 Continuity.
The common wall for townhouses shall be continuous from the foundation to the underside of the roof sheathing, deck or slab and shall extend the full length of the common wall including walls extending through and separating attached accessory structures.
and those that don't 
BTW the reason it is not specifically mentioned in the IRC is that the IRC covers single and 2 family homes only, the requirements for larger structures are more stringent.
