Foundation Grade Problem

snuddenstang

I am adding a family room addition 18x22, crawlspace, block foundation. The grade around the current foundation has only around 2-3 inches of exposed foundation. The town requires 6 inches of exposed foundation. The addition floor will be the same as the existing floors in the house. Any ideas on how to deal with this issue. I cannot just grade the yard as there are lawn sprinklers all over.

tkle

Build your foundation out of 12" block with a course of 6's on top.The 12's supporting the floor and the 6's supporting the wall.

snuddenstang

So then you would essentially have 2 seperate sill paltes. 1 for the floor system and the 6 inch for the wall system?

Driftwood

Also ,You could install a short retaining wall several ft. off the new work,giving you a walkway around it. They shouldn't be able to address the existing home,it's signed off.

Edsollen

Just completed a 2 room addition with the same concept, we used 10 inch block with a row of 6 inch on top. i dropped the siding down to the top of the 10 inch block. Worked fine.
Joel

tkle

Tens would work also.Yes you would have two different plates.The 6" block would be the bottom 8 inches of your wall.Your drywall could overlap and bonded with glue or furring strips could be used,leaving room for foam insulation and a way to nail your molding.
An adjacent retaining wall or curb as suggested would also serve your purpose.You could possibly bring it around the existing house so you could restore it's clearance.It's good to have to keep water and termites away.

Edsollen

Used 2x8 floor joist on the 10" block so the floor was up to the bottom of the wall.

tkle

Yeah but that would be too easy.

snuddenstang

Is there any way to achieve this using 8" block as that is what is on my plans.

Driftwood

The floor rim is all the bearing You need! Ever see a ledger bolted to a masonry wall? Keep it simple. Don't forget p.t. lumber at concrete wood contact!

snuddenstang

I was just thinking of that. I am uning 8" block. How would you fasten the Rim joist to the block? Would you drill into the block and epoxy lag bolts? I am using PT wood for my sill plates.

tkle

A 6" block on top of the 8" would still give you the same bearing as a ledger while still maintaining your 6"outside clearance.Possibly a 4 hi.

tgeb

What I have suggested a few times and has worked out well is to bump the block "out" 4" to give you a brick ledge. You can then proceed with the framing as you typically would, add a few courses of brick around the perimeter. Make sure that you waterproof what will be below grade and you have a good looking solution that will keep your framers happy.

If the job has budget, I always recommend that they run the brick up to the bottom of the windows, then run a row lock along the top.

__________________
Tom

www.gebcon.com

snuddenstang

When you say bump the block out 4". Are you still using 8" block?
I am using 2x6 framing also, not 2x4.

snuddenstang

Can you just plaster the sheeting on the rim joist over some metal lath?

tkle

I'd go with a good coat of latex paint

Tom R

Just saw this post. Here's one I did (right here in Jersey) a few years back with 8" block, - - similar situation with the grading.

If you didn't figure out how you're doing it yet, - - maybe I can 'dig up' the plan

snuddenstang

Tom,
How did you achieve what you have done there? I can't really see what is going on in the pictures.
Thanks, Mike

Tom R

Basically just bolted the rim joists to the walls, - - can't remember for sure, - - but I probably used 1/2" wedge or sleeve anchors (red-heads) and tapcons. The homeowner signed-off on the (lack of) foundation vents, he didn't want them. If he did, - - I'd have had to put them slightly below grade in area-wells. I lined everthing up so there was still a sill plate on top of the block wall, - - and my sub-floor sat right on top of it, - - then the wall framing on top of that. Here's my original drawing, - - hope you can make out the detail . . .

snuddenstang

Tom, When you bolted the ledger to the wall, did you just use a hilti and shoot nails into the block? How far apart?
Did you sink your anchor bolts into the sill so your subfloor could go right over them?