I want to put a bath upstairs do I need to strengthen the floor joists

Hey Stephent:

If they are regular joists (2"x8", 2"x10", etc... )... then should not be issue if you have approximately 16" center to center of floor joists. If joists are 24" on center then will be a good idea to install extra joists under future tub area at a minimum...may want to add other joists as well.

If you have 2"x4" joists (I have actually seen this) then you have major issue and should not plan on bathroom here unless you can rip out and increase size of joists.

If 2"x6" joists then you should probably plan on doubling the joists up under the tub area.

Let me know if this all makes sense...

MARK