Results 1 to 3 of 3
10-03-2014, 01:57 PM #1
ATTIC SEPARATION- 4 UNIT 2 STORY CONDO
Inspected a condo in a 2 story, 4 unit building. CMU partition wall down middle of building up to attic floor, 2 units on each side, one up, one down. An OSB sheathed wall runs from top of CMU wall to roof deck directly between units. Interestingly, part of this wall has two layers of OSB 9" apart, some one layer of OSB. But, each attic was open to the attic above the common covered upper walkway which provided entry to each upper unit. In other words, I could walk out of one attic, into attic above common area, directly into adjacent attic. Each unit is approx, 1850 SF, but attics also cover exterior porches and the common area.
I mentioned this to Agent and she provided a letter written by Architect in response to prior Inspector who seemed to be questioning the adequacy of the OSB separation wall. Letter stated that building was built to 2002 NC Building Code- building classification R-2.
He referenced Chapter 7 Section 708 "Fire Partitions" Paragraph 708.4 stating "If the partitions are not continuous to the deck, and where constructed of combustible construction, the space between the ceiling and the deck above shall be fireblocked or draftstopped in accordance with Sections 716.2.1 & 716.3.1 at the partition line."
He also mentions the same paragraph's Exception 5 that states that "Fireblocking or draftstopping is not required at the partition line in Group R-2 buildings that do not exceed four stories in height provided the attic space is subdivided by draftstopping into areas not exceeding 3,000 square feet or above every two dwelling units, whichever is smaller."
I believe he is stating that the OSB is allowed as fireblocking or draftstopping for this type of building. I believe he brings up Exception 5 as a backstop as if that would preclude need for firestopping or draftstopping anyway. I do not follow this, because if each unit is 1850 SF, plus the attic area over common area and porches, we get well over 3000 SF.
I also wonder if 716.4.2 isn't relevant. This states "Draftstopping shall be provided in attics, mansards, overhangs or other concealed roof spaces of Group R-2 buildings with three or more dwelling units and in all Group R-1 buildings. Draftstopping shall be installed above, and in line with, tenant and dwelling unit separation walls that do not extend to the underside of the roof sheathing above. There are 4 exceptions to this but I do not believe any apply- no sprinklers, no corridor separation, and attic areas are more than 3000 SF.
Also, any reason this building shouldn't have a firestop at upper ceiling around fireplace flues? Meaning, code for this R-2 building under 2002 rules.
I would greatly appreciate help from some of you learned Code experts as soon as you can. I love to get as much education as I can before I open my mouth.
2- PARTITION WALL
3- DOUBLE OSB
4- SINGLE OSB
5- OPEN TO ATTIC OVER COMMON AREA
6- END OF DRAFTSTOPPING WALL BETWEEN UNITS
7- ADJACENT UNIT
8- FIREPLACE FLUES NO FIRESTOP
John Pavan, Accurate Home Inspector, LLC, Southern Pines, NC
Last edited by JOHN PAVAN; 10-03-2014 at 02:05 PM.
10-03-2014, 02:56 PM #2
Re: ATTIC SEPARATION- 4 UNIT 2 STORY CONDO
Given that two units exceed 3000 square feet, what you should see is "Draftstopping shall be installed above, and in line with, tenant and dwelling unit separation walls that do not extend to the underside of the roof sheathing above." (from the 2002 NC Building Code).
Your photos do not show that.
That concrete block wall should have a solid lintel across the top of it.
The tops of all walls and concealed spaces should be fireblocked, including the wall/concealed space with those two flues/chimneys/whatever they are ... keep in mind that those should not be in contact with insulation, that an insulation baffled is required around them, as well as an approved firestop device (and I don't recall having seen any firestop devices for two - each separate firestop device would likely require those to be farther apart.
Too much wrong in those photos to detail everything - recommend having the city/county verify it is per the codes at the time of construction (it isn't, but it they say it is, then "it is", so to speak). The city may want an architect or engineer to sign and seal that it is okay (the city/county will likely not want to touch it except through a signed and sealed letter from a suitable design professional).
Was the "letter written by Architect in response to prior Inspector" signed and sealed? If so, the above has already been addressed, if the architect just provided a letter, not signed and sealed, then the letter is basically worthless in saying that is okay.
10-04-2014, 04:01 PM #3
Re: ATTIC SEPARATION- 4 UNIT 2 STORY CONDO
Just wanted to thank you for your quick and thorough response. I did the Report on this unit today, and it was very helpful to have been able to run this by someone with your experience.
Accurate Home Inspector, LLC
Southern Pines, NC