Irregular structure R301.2.2.2.2 #2

[righter101]

This section in the IRC spells out what is "irregular", not under the prescriptive code reqs, thereby requiring design. Does anyone here apply this to attached appurtenant strucutres??

Specifically I am wondering how you review items such as covered porches that have the roof not supported by braced walls. Another item would be, say, a garage built prescriptively, then they want to attach a shed roof to one side, creating a carport. Basically a post frame wall with rafters attached to a ledger on the garage.

Do you require engineering? How do you treat these type of structures??

We have generally allowed shed roofs and covered porches up to 6feet from the building, by applying the exception in #2.

The issue has come up when people are proposing to do something that has a project cost of $1500 or so. They are already coming in voluntarly and will be paying a $120 permit fee. It seems a bit much for me to require engineering that would potentially cost more than the project itself. I realize economics can't dictate safety so I am wondering how you all deal with these type of situations.

Thanks in advance to everyone.

 

[peach]

Re: Irregular structure R301.2.2.2.2 #2

I'll address the easy one first.. the detached (assumed not a dwelling).. most jurisdictions won't worry about the lean to attached to it (although it may be a zoning issue).

The main structure: If you can break the structure into a series of "regular" structures (squares and rectangles), you can analyze them separately.

If the screened porch shares the same roof as the house, if it offsets more than 4', you may have a problem. A separate "structure" like an aluminum roofed screen room, needs to stand on its own. If you are in a high wind area, engineering is probably required.

When I was in Florida, more than once, I saw pool enclosures flipped over the main house, but no damage to the main house.

 

[D a v e W]

Re: Irregular structure R301.2.2.2.2 #2

If it requires engineering so be it. You are approving the design remember. If it does not fit perscriptively then you have no chioce. And if thats the case make sure you keep an updated resume handy. :lol: