You need to know the design of your footing(s) and also to calculate the loads that will be transferred from the roof and storage area above to your new beam.  Once you know these loads, you can design the beam.  once you know the design of the existing footing and the soil bearing capacity beneath the existing footing (or just use a conservative number), you can decide how you would like to support the beam.  If you have a continuous wall footing now, you may have to enlarge the fooring at locations of isolated columns that will be used to support the new beam.  You also need this information for shoring purposes while removing the load bearing wall.  I hope this helps.  Good Luck!

Thanks for your advice

I was hoping that the 2X8 cieling joists, ceiling drywall and plywood of a span 24 foot by 15 foot room wouldn't require alot of beam/support. AND mainly because I do not know the math to calculate these loads. The roof does not seem to be supported by the bearing wall.

your help much appreciated, Thanks again

Hire a local structural engineer to calculate the required beams and footings.

What?! no formula, no do it yourself suggestion? other experiences?

Go hire a guy!?

thanks for the thread ending insight

Hardworkingguy,

As a practicing structural engineer, I have been called in several times by other "hard working guys" who thgought they could do the similar thing you are proposing.  The difference between them and you, is you asked first and someone suggested to you hire a structural engineer, these other guys, waited until after it was built and had problems.  

Since I was called in afterwards to clean up after the elephants, my fee was about 2.5 times what it would have been if they called me in up front. And lets not talk about the re-work costs and the "wife" factor.

So since you are a hard working guy, you should waste your money to hire someone (and pay them about 2 times what it woulkd cost) to fix your mistake.

So while it sounds like a "brush-off" to go hire someone, it is the best recommendation anyone could give you.  

A good, creative structural PE can save you many times his/her fee by showing you the best solution.  In this case, perhaps sistering the joists would be stiffer and cheaper.

Deflection almost always governs.  An upturned beam may work.  6" members can rarely span 24' without sagging too much, even if made of "unobtainium".  Flitch beams are inefficient, roofs are complex, plaster is brittle...

I've said too much, hire a good engineer and save both money and aggravation.

For one thing a structural engineer will be able to tell you what kind of deflections you will see in your structure due to the removal of a continuous supporting bearing wall.  The deflections may contribute to ather areas where cracking and perhaps additional loading could be of concern.