Type IB - rated floor assembly required over crawl space?

[steveray]

Although, I think most shipping containers use wood sheathing for their floor (either nominal or 1" T&G marine-ply). This could have been another issue with the Type I-B designation.

Yep...back to the earlier note.....But honestly I don't think they are "structural wood", just a wood finished floor...

 

[classicT]

Yep...back to the earlier note.....But honestly I don't think they are "structural wood", just a wood finished floor...

From the ones I've seen, there is a steel member acting as a joist, and the wood floor is acting as sheathing.

 

[steveray]

From the ones I've seen, there is a steel member acting as a joist, and the wood floor is acting as sheathing.

View attachment 12238View attachment 12239

So structural then for those playing our home game.....

 

[Penguin87]

• thank you all for the feedback and points @classicT @steveray @Yankee Chronicler ! it gets a little complicated, to give a little more context on the issue and project:
  • the hotel/resort is spread out over about 10 acres, in a rural area, with a clubhouse and pool, mixed used non-separated, and fully sprinklered NFPA 13
  • the hotel design was based off of prototype shipping container units on a nearby site that is in a moderate WUI. the prototype plans were approved by the city and state, and the design and construction type (IB) was used as a basis to streamline the approvals of the larger project. the larger site is only a few miles down the road and not in a WUI.
  • the following design changes occurred while the plans were in the city dues to ownership requests:
    • original design was composed of repurposed shipping containers (14ga continuously welded steel underbelly, roof, and exterior walls) where fire rating was hardly an issue. plus it has approved alternate means of construction by the state. the owner selected a container fabricator without fully sharing the bid details, but the fabricator stated that they could meet the design intent using purpose built instead of repurposed containers.
    • the original design was also slab on grade (which was changed to crawl spaces after the LAHJ submittal) for ease of site installed MEP connections, and ratings were not an issue on the floor with SOG. This was requested by ownership late in the process, and the change was accepted by the city.
• While I agree the construction type is excessive, it was stated in the contract documents from the start of the project; despite the changes and fabricator statements. Now that they are almost in fabrication of purpose built containers, they are expressing issues, and are stating that they cannot meet standard container criteria listed in the architectural and structural drawings.
• The plans were approved by the city as Type IB, therefor I do not see how 602.1.1 would apply in the reverse situation that the approved construction type is greater than that proposed by the fabricator.
• I am left either continuing to push back on the fabricator to uphold the contract docs, since it was largely an overlook on them, for not meeting the BOD parameters, but also a huge challenge, or alternatively submitting a revised design and construction type change (to IIB, IIIB, or even propose VB since it appears within the allowable area of the project) to the city while the project is under construction. So I am trying to weigh my options, but both have cost and delay implications.
• a caveat is that the fabricator still needs to submit the module designs to the state and obtain approval for the modular portions of the project, which are largely excluded from local jurisdiction. the fabricator thinks this is a local building official oversight, but I disagree and think they have every right to uphold the original construction type of the project in it's final site installed form.

Just reclassify the construction to Type VB if thats doable, it should have been done that way in the beginning. If the areas work, there should be absolutely no reason to have to permit a single story structure above VB.
The AHJ should be amenable to that as long as you meet all the life safety requirements. I recommend giving them a phone call to walk them through it however.

Edit - you can't use plywood in Type I/II type construction. You would have to use metal deck, concrete or something like DragonBoard (Mag Oxide panel) to achieve a noncombustible and fire rated floor decking.

 

[Yankee Chronicler]

Edit - you can't use plywood in Type I/II type construction. You would have to use metal deck, concrete or something like DragonBoard (Mag Oxide panel) to achieve a noncombustible and fire rated floor decking.

US Gypsum makes 3/4" thick structural panels that are cementitious. I believe they would be acceptable in Type I construction. They should certainly be acceptable in Type II construction.

STRUCTO-CRETE® Brand Structural Panels | USG

STRUCTO-CRETE® Brand Structural Panels are durable, noncombustible concrete subfloor panels that offer fast installation and structural stability.

www.usg.com

 

[Penguin87]

US Gypsum makes 3/4" thick structural panels that are cementitious. I believe they would be acceptable in Type I construction. They should certainly be acceptable in Type II construction.

STRUCTO-CRETE® Brand Structural Panels | USG

STRUCTO-CRETE® Brand Structural Panels are durable, noncombustible concrete subfloor panels that offer fast installation and structural stability.

www.usg.com

Yes, Structo-Crete meets ASTM E136 testing for noncombustible material.

 

[steveray]

Just reclassify the construction to Type VB if thats doable, it should have been done that way in the beginning. If the areas work, there should be absolutely no reason to have to permit a single story structure above VB.
The AHJ should be amenable to that as long as you meet all the life safety requirements. I recommend giving them a phone call to walk them through it however.

Edit - you can't use plywood in Type I/II type construction. You would have to use metal deck, concrete or something like DragonBoard (Mag Oxide panel) to achieve a noncombustible and fire rated floor decking.

Correction....there are limited uses for plywood in type 1 and 2 construction...not allowed for a structural subfloor but can be used as a floor finish...