[tsperry]

I am framing an exterior wall in my basement (against concrete block). Is it necessary touse a top plate when framing or could I just anchor the 2 x 4 frmes to the floor joists? If not, why not?

Thank you!

 

[tcleve4911]

Using a top plate is the preferred method to maintain straight lines and ease of layout for framing.
Not ALL the studs are going to land exactly on a floor joist.

However if you choose to do it that way:whistling2: I don't see any structural issues.

 

[Gary in WA]

Yes, it is necessary for fire code compliance. If you have a fire start in an electrical outlet in the wall, it could easily and quickly travel to the floor bays above, across the floor and follow a wiring/plumbing hole to the second floor space or attic. Code (minimum) requires fire blocking at wall top plates and every 10' lineally in the wall or behind it; http://publicecodes.citation.com/icod/irc/2009/icod_irc_2009_3_sec002_par031.htm

http://publicecodes.citation.com/icod/irc/2009/icod_irc_2009_3_sec002_par032.htm

Please check locally with your Fire Marshall or Building Department.

Gary