Frame Concrete Half Wall in Basement

VikingDinKC

Hello

In my day light basement, I have a concrete wall that is almost 4 foot high and then the rest of the wall is studded to the ceiling which is about 8’5’’. This weekend, I am going to frame this half wall. The idea is that I would like to create a ledge where the concrete transitions to the studded wall (since the concrete already comes out farther than the studded wall, then I used 1 inch XPS insulation against the concrete, ½ inch gap and then a 2x4 bottom sill plate so I am looking at about a 7 to 8 inch ledge). I am not sure if the ledge will be tiled or just a stained wood. My question is, do I build the half wall so it is level with the concrete (height wise)? My other option is that I could put a pressure treated piece of wood on top of the concrete and then build the wall the height of the concrete plus the 2x4. I am just seeing how others have approached this. I do have 2 windows which are above the concrete.

Thanks in advance for any feedback you have.

titanoman

Yes. Put treated board on concrete, with seal sealer, then build half-wall to that height.
That way, its there to secure framed wall nicely, and gets all material a little father from the concrete to alleviate any moisture issues with whatever you go with.

Canucker

Put some xps on top of the half wall, then frame up level with the foam. You insulated the bottom portion, don't forget the top.

kj6887

Keep in mind your window elevation. You want to make sure your finish ledge is not above the window sill, this makes for difficult and sometimes odd finishing.

VikingDinKC

Thank you for the feedback. I have done a number of Google searches and there does not seem to be a standard way to accomplish this. I like the idea of putting the XPS foam on top of the wall as well and then I could seal it with tuck tape so it would create an air tight seal all across the wall. The other idea I had was if I used pressure treated wood on the top, I could us those boards to support the wall instead of having to use tapcon screws and anchor them to the wall. Also, I have enough space below the window to put a pressure treated 2x4.

http://hostedmedia.reimanpub.com/TFH..._FRABMT_11.JPG

This image has been really helpful for me but my situation is a bit different since my concrete ledge is a bit wider and they built the wall above the concrete. It makes me wonder if there is a standard height for ledges. Also, they did not put the XPS board on top of the wall.

Canucker

You don't have to put it on the top of the wall. If i put the effort into insulating it though, why not completely seal it, just like you said?

VikingDinKC

I am using the XPS foam board as an insulator and a vapor barrier to prevent moister from causing mold to form on the fiberglass insulation. Also, there is probably value in putting the foam board on top of the concrete to prevent the ledge from getting too cold. For example, if I use a tile, with it having pretty close contact to the cold concrete, it could cause it to get cold as well. The only other item I am thinking about is putting the 1 inch foam board down, is that it gets the ledge closer to the window. I am already concern that I will not have enough space to put trim around the bottom portion of the window. Maybe that is something that is not a big deal.