How do you replace sill plates and studs that are damaged by termites. Treated but need to repair detached garage. Damage to studs is about 2 to 3 feet off floor. Also slab is not high enough, any suggestions?

You will have to build a temporary wall about 2' inside damaged wall.

Cut out the damaged section of studding and sill plate.

Replace plate with pressure treated lumber and sister new studs to existing going from top plate to new sill plate.

Remove temporary wall.

Need more info on concrete floor height.

Chuck

Grade of yard is a lot higher than garage, due to my
Grandfather having a garden. Unfortunately he raised one side of the yard to make the garden and everything drains toward the garage. I have dug some drainage trenches and sloped the ground away from the garage toward the drainage. The moisture was the problem in the first place, which attracted the termites. Is there some way to put a curb (if you may) on top of the slab and build new wall on other side of curb?
Back to replacing sill plat and studs. What about the bolts and screws that are still in place? Do I just go around them or cut them off? Sorry not too familiar with these issues, but reading a lot.

The bolts in concrete where the sill plate goes should be reused to hold new plate down. Before you put in sill plate put a termite shield down and the plate on top of it.

Between the shield and slope away from slab you should be good.

Chuck

The bolts in concrete where the sill plate goes should be reused to hold new plate down. Before you put in sill plate put a termite shield down and the plate on top of it.

Between the shield and slope away from slab you should be good.

Chuck

Thank you so much for your advice. It is hard to get help locally, from a professional. Just one more, what is termite shield?

It is a piece of metal flashing that is set under the sill and sticks out about an inch. The part sticking out has a slight downward pitch.

Should be able to get it at any of the big box stored.

Chuck