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Group U Structure Building Envelope Requirements (Roofing and Walls)

BuildingFlorida

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May 4, 2022
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14
Location
Florida
I am working on a first responder training facility built with shipping containers.
It will be 2 wide x 3 long and will be 2 containers high.
I believe this is a Group U facility. Please correct me if I'm wrong.

1) Roofing
1.1) What are the roofing requirements for this type of facility?
1.2) Is a pitch required?
1.3) Is a formal roofing system required or are the metal container roofs sufficient?
1.4) What codes should I refer to?
1.5) Are there any levels of watertightness required?

2) Walls
2.1) Are there any levels of watertightness required?
2.2) What codes should I refer to?
 
Why do you think this is a Group U occupancy? For what will the structure be used?
 
I understand that, but it does not tell me exactly what is happening inside the structure. What are the specific uses of the structure (e.g., classroom, storage, offices, etc.)?
It's for tactical or swat training. It's to simulate a building or warehouse environment...climbing of stairs and ladders. Entering though windows and doors. This is ALL it is used for.

For about 10 to 20 people at a time.

No classrooms, storage or offices.
 
It's for tactical or swat training. It's to simulate a building or warehouse environment...climbing of stairs and ladders. Entering though windows and doors. This is ALL it is used for.

For about 10 to 20 people at a time.

No classrooms, storage or offices.
Okay, that makes sense, but I had to ask because I am seeing more and more uses of shipping containers for occupied structures.

In my opinion, you do not need to do anything to the containers unless you want to maximize the life span of the structure by preventing corrosion.
 
Thanks for the comments!
Okay, that makes sense, but I had to ask because I am seeing more and more uses of shipping containers for occupied structures.

In my opinion, you do not need to do anything to the containers unless you want to maximize the life span of the structure by preventing corrosion.

So...no code requirements for roofing?
 
Thanks for the comments!


So...no code requirements for roofing?
Just think about this, shipping containers keep their contents dry while being transported on container ships, trains, and trucks. They are exposed to all kinds of elements during their journeys. Unless they are damaged or compromised in some other way, they are probably more resistant to weathering than many Type V buildings.

If there is nothing of value inside the containers, and water will not collect inside (i.e., there are weep holes), a roof would be unnecessary.
 
Just think about this, shipping containers keep their contents dry while being transported on container ships, trains, and trucks. They are exposed to all kinds of elements during their journeys. Unless they are damaged or compromised in some other way, they are probably more resistant to weathering than many Type V buildings.

If there is nothing of value inside the containers, and water will not collect inside (i.e., there are weep holes), a roof would be unnecessary.

Well...if two containers are side by side...there's still a gap between the two. The containers have openings inside so people can walk from one to the other. Rainwater will makes its way from the roof through the separation between the containers (even if the top of the container is sealed)...down the outside of the wall panel and then drip down into the interior space through the opening header. If there's no roofing, then the whole thing will leak badly.

But...if the code says this is OK...then it's OK. But...I don't think this question has been answered. Does the code allow for a Group U to leak?
 
There is nothing in the IBC that requires a structure to have a roof. Many Group U occupancies listed in Chapter 3 do not require roofs, or the roofs typically do not comply with the requirements of Chapter 15.

Roofs would only be necessary if the intent of IBC Section 101.3 would not be met in the absence of a roof. If water entering the structure is detrimental to the integrity of the structure, a reasonable level of safety for those using the structure is not provided. Therefore, a means of mitigating moisture intrusion should be provided.

Since container roofs are usually crowned to direct water to the long sides of the container, a gutter system can be installed between the two rows of containers to collect the water. Downspouts and leaders can direct the water away from the structure. You can add a fluid-applied roof coating to ensure any gaps or penetrations are sealed or use polyurethane foam roofing to achieve the same thing but also provide some insulation.
 
Weld a plate over the gap, or apply an isolation board then a membrane roof.

Check on the Fire Fighter training buildings made from containers, bunches of container stacked and welded together without roofs, we even light fires in them.
 
Thanks for all the comments. All have been helpful. I hope to provide an update as to how we made out with the AHJ in a few months.
 
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