In my basement I'm looking to add a couple partition walls. At the bottom of the joists a lot of the copper plumbing and electrical wiring run along it. Is it OK to just have a bottom plate and studs running to the joists with no top plate? Especially if it's 2 2x6' against each other? I noticed a couple areas in the basement that were done like that already. One was a closet I opened up and another is the room that was built where the furnace/hot water heater is. I googled about partition walls with no top plate and studs to joist but can find no info, if it's allowed or commonly done. I'd post a couple pics but I see no options for attaching pictures. Thanks

 

Welcome to the forums. You will need a top plate for the partition wall to keep it straight. You can build down cripples from your joists to capture the top plate and eliminate the need to put the plate flat against the joist bottoms. Posting a picture of what you are dealing with would help. http://www.doityourself.com/forum/el...your-post.html

 

The only issue I can see is there will be no fire block between the wall cavity and the joist cavity. This could be fixed by adding some blocking lower down the wall.