[Sereguial]

New to construction forums so bear with me if I don't use all the same terms as everyone would expect.
I have a walkout basement with the front and side walls formed concrete and the back wall is a 2x6 wood frame. The joists run perpendicular to the back wall and the house is a two story (plus the walkout basement). House was built in 1968.
The basement was finished in mid 70's and has MANY issues, most I know what to do with. I am demolishing the basement (going to leave it unfinished for now, just want to fix electrical and plumbing problems), and I found a major problem.
The bottom plate and bottom 1.5-2 feet of several studs on the back wall is rotten and I saw active termite infestation.
I am getting an exterminator come out for the termites but the rot looks to be a bigger problem: the ground out back is more or less flat but grades slightly away from the house but the bottom sill looks like it is at ground level (or slightly below in some areas.
Ok, LOTS of background but here is my question:
Should I replace bottom plate and studs as is (using PT wood of course) or should I build up a 6" or so concrete (or block) at the bottom of the wall to put the sill plate on to prevent this problem in the future? I am looking for options to consider and where to go from here.
Thanks in advance for the help!
Chris (in southeast NH)

 

[Ron6519]

If you feel this will be an issue again, I'd raise the area and put the sill plate higher.
Ron

 

[Sereguial]

Thanks for the quick response, figured it would be the best option to prevent the problem again since PT wood isn't 100% against all rot and pests. I am just not sure on details of how to raise it up. Having said that do you think I should lay a small concrete raise over top the existing foundation or put in blocks? Another thing, how tall to make that raise (how far above ground level should it be)?

 

[Ron6519]

Thanks for the quick response, figured it would be the best option to prevent the problem again since PT wood isn't 100% against all rot and pests. I am just not sure on details of how to raise it up. Having said that do you think I should lay a small concrete raise over top the existing foundation or put in blocks? Another thing, how tall to make that raise (how far above ground level should it be)?

Unless there's something about the surrounding slope you're not telling us about, I would think a 6" curb would do it. Dowel it into the slab and install sill anchor bolts into the curb every 3 ft or so.
Ron

 

[Gary in WA]

Make sure to use 8" wide block for the two-story. Anchor bolt within 12" of ends of p.t. plate. Termite shield on block, then sill sealer (thermal/capillary break), then plate. I'd go so far as Grace-Ice&water shield on bottom area and edge of sheathing, then flashing touching t.s., then builders paper or house wrap lapped over that. Think like a rain-drop.....

Gary