Lateral design for residential decks in Canada 1

[Woody1515]

Hi everyone,

I have noticed the IRC has requirements for a deck lateral load connection, which seem to be typically done by installing multiple deck tension ties attached to the deck joists and interior main floor joists. Is this lateral connection required for decks in Canada? I cannot find anything in the Canadian code that states this is a requirement, and I’m fairly certain most decks in Canada are built without the use of these ties. Also, would these tie backs typically be used for a typical addition with walls and a roof that are attached to the existing house, or just decks?

Thanks in advance!

 

[phamENG]

Can't speak to Canadian codes, but I'm pretty sure that Canadian decks have to obey the same laws of physics as ours do, so completing the collector load path for the diaphragm is just as important whether it's officially codified or not.

I've used details like that on sun rooms and porch roofs where I can't get any LFRS in the addition. But that requires invasive work inside the building that a lot of people don't like.

 

[skeletron]

NBCC (or more specifically BCBC) does not specifically address lateral design for residential decks. The closest references are Article 9.23.6.2 and this publication. If you do a search for "residential deck design bc" a number of municipalities sample requirements show up. The focus appears to be mainly on durability and water, with nothing shown that represents AWC's DCA6 or the IRC requirements the OP has noted. It is implicit, though, that decks should still be designed to meet the requirements of Part 9 or Part 4. I just rarely see anyone explicitly addressing this on the files that come across my desk. I can't even walk my dog around my neighbourhood without spotting at least a handful of poor deck designs. With regards to additions, I would typically design them to handle their own seismic load and/or whatever component of the load that they are replacing. In many cases I'll also tie them back with straps or staggering the plywood over the joint.

 

[lexpatrie]

https://www.structuremag.org/?p=1353