Expert: Dave Johnson - 7/12/2008

Question
We are replacing our covered deck deck and extending the dining room wall.  
We need to know the recommended limit to extend out a wall past the steel
beam that runs parallel for a load bearing wall.  The floor joists are 2x8
placed 16 inches apart.  We are considering an extension 3 or 4 feet beyond
edge of steel beam.  The roof is attached to the side of the house and covers
the 24 feet span of the deck and room.  How far can you counter lever  a
room off of a steel beam?  Thank you for any assistance you can give.

Answer
Hi Denise,
With 2"x8" anything over a 24" cantilever is pushing it. You also need to attach the new joists back onto the existing 4' making the new joists 6' long.

I'm assuming that you are talking about the house joists and not the deck?
Mail me back with a bit more info, please.
Dave