On Mar 12, 4:10*pm, wrote:
On Mar 12, 1:16*pm, wrote:

Trying to build a deck. I looked in the basement of my house. My house
appears to be built without a rim joist. There is just wood i-beams
that sit on top of the foundation. Then plywood on the outside of the
house. How do I secure a ledger board?

The building code doesn't seem to allow a free standing deck because
the posts need to be 4 foot from the house.

I've read something about blocking but I've been unable to find a
detailed description of how to accomplish this.

Is it possible that from the basement you are seeing an LVL rim?
(similar to a microlam beam only not intended to carry a load). *They
look similar to plywood or OSB. *It seems fairly unusual (from my part
of the world) that there would be no rim (or a treated mudsill on top
the wall). *If you know the thickness of the wall, you can measure
from the face of what you see to the edge of the wall and get an
estimate of the thickness of what you are seeing. *If it's an LVL rim
board you should be reading a thickness of 1-1/2 to 1-3/4".

If indeed there is no rim another possibility for the deck addition
would be to extend your deck joist through the wall and over the top
of the foundation wall just like your floor I-joists are. *We have
done that regularly over the years for a variety of reasons
(especially short span decks/balconies when we don't want posts at all
- they are cantelievered from the building).

I'm assuming you would be removing siding anyhow to place your ledger
board. *Now you would have to do some additional work - including
removing that plywood rim (if that's what it is). *You would want to
add squash blocks to the web of the I-joists so you have a good
surface to anchor your deck joists. *The deck joists are set tight to
the I-joists (with the squash blocks filling what would have been a
void between them. *Then you add solid blocking between each set of
floor-joist/deck-joist combinations under the wall above (almost like
a rim joist would have been). *Of course I haven't mentioned that your
floor and deck joists are going to be different heights (at least
slightly) and you need to decide if you want them flush at the top or
if you want the deck stepped down slightly. *We have snow in my world
so we usually opt for stepping the deck down slightly even though it's
not handicapped friendly (it keeps melting snow from sneaking into the
patio door). *The approach you take will require some additional
blocking to keep everything solid. *One more thing. *Don't extend your
deck joists more than 12" into the house. *In the old days there used
to be codes about "over-extending" lapping joists more than a foot
past the bearing point. *I don't really remember what that was about -
probably something to do with warping, cupping, etc.

I would make a sketch of this for you if I could. *I think a detail
drawing is worth a thousand words. *I just joined this group today and
need to figure a way to share sketches efficiently if I'm going to
hang around - I tend to be visual. *Good luck, I would be interested
to see some followup as to how this unfolds.

need to figure a way to share sketches efficiently

Find a website to which you can upload your sketches and post the link
in this group. Based on the multitude of ways people read this group.
I doubt you could come up with a way that all of your sketches would
be viewable (correctly) in the newsgroup.