Deck Lateral Connection to Brick House 2

[Simba13]

Morning all,

I'm working on designing the framing for a covered screened in porch. I've gotten all the vertical stuff mostly squared away but I'm scratching my head on the best way to handle the lateral. The Client prefers it to be free standing since the house is brick and from what he's told me, he has had issues in the past getting the ledger connection to pass county inspection for brick houses. I haven't been able to find a detail on the proper way to attach a ledger board through a brick facade (if there even is a proper way). So I looked at the requirements for free standing and the county requires tension ties in addition to knee bracing (based on post height), but according to the details I'm seeing, tension ties are attached to the sill plate... I don't need the bearing from the house but it seems like I can't get away from restraining it to the house laterally. Do they just drill through and epoxy bolt it or something?

Any tips or tricks of the trade would be very much appreciated.

P.S. I read Medeek's post on lateral bracing for free standing decks, it was definitely helpful.

 

[phamENG]

Take a look DCA 6. It should help.

 

[r13]

Can you show us some sketches, plan, elevation...

 

[BAretired]

If designed as a free standing structure, it should not need to be connected to the house.

BA

 

[Simba13]

 

[Simba13]

Probably a no go to send our sheets off into cyberspace. So I attached a couple PNG's one of the bracing detail and one of the floor plan (there is also a roof framing plan, and a couple more details but I think this gives a picture) Not 100% done with the elevation yet though. Basically it's about 3' from the ground to the deck, then a 8' ceiling for the screened in porch.

The house would be at the top of the framing plan. That's why I put a bit of an overhang there, so the footers would have a bit of room without being on top of the house foundation.

 

[jjl317]

Simpson Strong-Tie has a number of products to laterally attach decks to existing structure, including some through brick veneer. I think that there have been some previous posts on this site about them.

 

[r13]

I am not a wood guy, sketch below is just my random thinking on making it a self-stand enclosure.

 

[BAretired]

I don't think what you have shown is suitable as a standalone structure.

You stated it is covered, so there must be a roof structure as well as supporting posts. Have you considered wind forces on the screened walls? Will there be a flashing detail at the roof/brick junction?

You need wind bracing on Grids A, C, 1 and 2 which has to be taken down to the foundation.


BA

 

[r13]

Bracing in the E-W direction is a challenge, even attached to the building, line 2 remains problematic.

 

[EdStainless]

In many locals if the deck is attached to the house it must be designed and built to the same rules as a house, from the footings up.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[r13]

Can wood beam be used to span the E-W direction, and can wood makes moment frame?

 

[Simba13]

Yep, I agree. It's definitely not done. I'd really like to have an attachment to the house for lateral support. I looked at the brick veneer attachment jjl317 mentioned. It's the simpson strong tie bvlz. Has anyone here used this before? Because to me it seems like that conflicts with the DCA 6 note about no attachments through brick veneer. But maybe this only applies to bearing?

retired13 How would you go about providing a moment frame here?

 

[phamENG]

The code prohibits you from bearing on brick, not through brick. The nice thing about the Simpson gizmo is that, theoretically, you don't bear on the brick. You have a compression strut in the steel rod that goes straight through and tension ties in the angled screws. You could put that in without the brick and it would still support the ledger. So you have no bearing on the brick itself.

Downsides: Installation seems like it would be tough to get right. I haven't spec'd or used them before, so I can't say for sure. Also, they don't list lateral load capacities. I'm guessing it's meant to meet code minimum requirements and be essentially the same as the bolted ledger connections in the IRC. The fact that they don't come out and say that gives me some pause, but a quick email to the regional Simpson rep should clear it up.

I missed before that you said you're putting a roof on this. When I'm doing a deck, I'm okay with code minimums in most cases. As soon as you put a roof on it and tie it to the house, the game changes for me. Now, differential settlement will likely damage the joint between the new and old roof lines, causing leaks and damaging the existing structure. Also, I've seen these things enclosed as conditioned living space with a deck foundation underneath. I know we can't be responsible for dumb things owners do after the fact, but I still like to make things a little more robust when it's more an extension of the house than just a deck tacked on the back.

 

[Simba13]

Hmm, you all have given me a lot to ponder. This is my first covered deck. It might be worth it to model it in RISA if only for my own education. I feel like just slapping knee braces on it isn't going to do the trick.

phamENG yeah, the thing that stuck out to me about the simpson attachment is that it goes through the brick to be bolted to the house floor system, but I don't know anything about the existing floor system... And trusting that the contractor attaches it correctly seems like a stretch. Also, I hadn't considered differential settlement...

Thanks for the advice

 

[XR250]

The Simpson Gizmo was discussed here..
[link thread507-471037]Link[/url]

 

[r13]

How would you go about providing a moment frame here?

Simba13,

That is my question for the wood/residential designers too. Maybe you have to design the two walls (blue in my sketch) as cantilever in E-W direction, and shear walk in N-S direction that without calling for moment connection.