How do I vertically level a basement 2/4 studwall?

[Rider]

Hello....I want to build a 2x4 stud wall to cover an uneven and disasterous looking cinderblock basement wall. In my effort to "plan ahead" I realize that that sole plate (2x4 PT), when laid flat along the lenght of the wall, does not sit at 90 degrees to the wall. If I conform to the concrete floor, the top of the stud wall will tilt out. So, should I use a levelling compound to level or cedar shim the bottom plate? Many thanks...

[Rich]

I would frame the wall laying down (if there is enough room) with a single top plate. Then stand the wall plumb and install the 2nd top plate to flush it to the bottom of the floor joists. Whatever happens to the sill plate (if it's not sitting flat) can be shimmed with cedar shims - but unless it's a structural wall I wouldn't worry too much about it not sitting flush.
Make sure to place the wall a 1/2"-1" away from the block wall so it's not touching the block.

[Rider]

Rich...great advice, thank you. My other problem is that the height between the floor and the joists above is shorter at one end. From one end to the other, the gap between the top plate (placed level)and floor joist grows to about 5"-7". (The house is 117 yrs old.) So, would it be sufficient to size the stud wall for the shorter end (built square on the floor and raised into place) and use 2x4's to fill the gap on the higher end and any gaps in between? Thanks again for your advice. Incidentally, I have a massive database of befor and after digital pictures that I've been taking. If my wording above does not make sense I can send a picture of the problem. Sorry to be long winded. Rider

[Rich]

Wow.. quite a difference. If you don't mind what it looks like - infilling with 2x material would be just fine. Although it does waste 2 continuous runs of 2x material to infill the 7". I would probably layout the wall right on the floor and measure and cut each stud individually. It is a little more time consuming but it does take care of the problem of wasting material. Hope that helps.

[Rider]

Rich..thanks again for taking the time to respond. I just took a second look and I think I'll cut each stud individually to avoid getting too fancy infilling. I appreciate your advice. I'm sure I'll be back on soon since I start the framing this weekend.

[Rich]

Right on - let us know how it works out for you.

[Dano]

Dealing with century old home renovations..I never..never ever find anything that's either plumb,square or level......Doing a wall like yours, I've even installed my top/bottom plate first and as Rich suggested, cut each vertical accordingly..time consuming but I gave up on attempting to save time years ago.....

[Rider]

Great. I'm definitely going that route. I'm happy to dedicate the time to do it right. There's not hurry...Thanks guys!