Fire rating interpretation

[grade971]

Per the IBC, construction type IB requires 2 hour rating for floor construction and associated secondary structural members.

If I have a 3 1/2" NW concrete slab on 1 1/2" metal deck (which has a FR of 1 hr) can I use mineral fiber insulation underside of deck between beams to raise the rating to 2hr? (The room below needs to be open to deck and thus no gyp ceiling)

Not sure if the 2 hr rating for IB construction has to be achieved independently by the slab on deck or it can be coupled with Insulation to acheive the rating ?

 

[TheCommish]

Ratings systems are obtained by the designer and installer providing a tested and listed assembly in accordance with an prescribed design, no by putting products together in layers and hoping

 

[Yankee Chronicler]

If I have a 3 1/2" NW concrete slab on 1 1/2" metal deck (which has a FR of 1 hr) can I use mineral fiber insulation underside of deck between beams to raise the rating to 2hr? (The room below needs to be open to deck and thus no gyp ceiling)

What are you proposing for the beams? It's not a 2-hour floor if the main supporting structure isn't rated for 2 hours.

 

[grade971]

What are you proposing for the beams? It's not a 2-hour floor if the main supporting structure isn't rated for 2 hours.

What are you proposing for the beams? It's not a 2-hour floor if the main supporting structure isn't rated for 2 hours.

For the beam I am proposing BXUV.D929

 

[Paul Sweet]

See if this is included in IBC 721 Prescriptive Fire Resistance, or use one of the spray-applied fireproofings that have been tested and listed for 2 hours.

 

[steveray]

I would think you could get there with spray (SFRM), but I haven't seen it firsthand yet....

 

[Yankee Chronicler]

I would think you could get there with spray (SFRM), but I haven't seen it firsthand yet....

That's the usual way this is accomplished.