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Landing subfloor materials

Kevin0616

Registered User
Joined
May 11, 2020
Messages
19
Location
Ottawa
Hello everyone,

For a part 3, noncombustible building with four stories. can I use wood subfloor for the landings?

Thank you in advance!
ZKW
 
Nope.... not on the list under Section 603.

1011.7 Stairway Construction
Stairways shall be built of materials consistent with the types permitted for the type of construction of the building, except that wood handrails shall be permitted for all types of construction.
 
Ty ... let me ask you about my stairs. 14 story building in Penn, it falls under 2009 IBC, type 1A, Assembly A-2 / Business B. There is a set of open stairs connecting 2 floors in a tenant space, in addition to the common stairs in a stairwell that connect all floors.

Stair construction is steel stringers and pans, with wood treads and landing. Is it a safe assumption that is acceptable, since the structural portion is steel? These stairs were installed during a full gut & reno about 3 yrs ago.
 
Ty ... let me ask you about my stairs. 14 story building in Penn, it falls under 2009 IBC, type 1A, Assembly A-2 / Business B. There is a set of open stairs connecting 2 floors in a tenant space, in addition to the common stairs in a stairwell that connect all floors.

Stair construction is steel stringers and pans, with wood treads and landing. Is it a safe assumption that is acceptable, since the structural portion is steel? These stairs were installed during a full gut & reno about 3 yrs ago.
Probably not what I would approve...but one could possible argue IBC 603.1 #10 or #19.

603.1 Allowable Materials
Combustible materials shall be permitted in buildings of Type I or II construction in the following applications and in accordance with Sections 603.1.1 through 603.1.3:
....
10. Finish flooring installed in accordance with Section 805.
....
19. Heavy timber as permitted by Note c to Table 601 and Sections 602.4.7 and 1406.3.
....
 
I could maybe buy heavy timber (but I would have to chase that down), but a "structural" tread is not FF IMO.....Wrap your steel/ concrete treads in wood


Upon further reading, if the stairs were installed and approved, then they are right...Regardless of code....
 
Hello everyone,

For a part 3, noncombustible building with four stories. can I use wood subfloor for the landings?

Thank you in advance!
ZKW
Hi Kevin,

Their answers are from the wrong code. This should be discussed with the building official to see if they feel it falls within the scope of 3.1.5.2. It is not specifically listed, but it does provide the official some latitude in approving other items under Clause (h): http://www.buildingcode.online/30.html. Personally, I would not accept it, but they might have a different opinion.
 
Then, does it make more sense to start with the assumption that it may be OK to penetrate, and discuss with officials later, or to start with a design without penetration?
 
I'd tell them what the penetration is for and see if they are OK with it. It's a huge job to move something later on.
 
Rule of thumb is that it is OK if the code REQUIRES it to penetrate. The code says this building needs sprinklers, that means the exit needs sprinklers and I have to run a pipe to that sprinkler. The code does not say I need a out let on the suite side of the exit enclosure, so I can't put it there.
 
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