drilling through steel I beam
In our 2-door double garage, I plan on placing storage shelving above the garage doors. There is a steel I beam running the width of the garage (parallel to front face of garage) about 6 feet back. The I beam is what supports the 2nd story above (so the garage sticks out about 6 feet from the face of the 2nd story). I plan on hanging shelving the full width of the garage, and 3 feet deep, so it will leave me with an additional 3 feet from the edge of the shelving to the I beam. I can support the shelving all the way around where it attaches to the walls, but no way of supporting it at the center (between where the two garage doors open fully into the garage).
I am considering having a beam (doubled up 2x6 or something similar) attached to the front face of the garage to just beneath the I beam. The shelf will only sit on 3' of this 6' beam. At the end of the beam, since it would be below the I Beam, I want to hang threaded rod between the steel I beam and the wood beam supporting the shelving.
Are there any issues with doing this? I would suspect that adding a few hundred pounds of weight to the I beam would be ok. Plus, most of the weight on the shelves would be supported where the shelf attaches to the garage walls.
One issue is that on the bottom of the steel I beam, there is another steel plate welded to it acting as a sill for cinder blocks. I suspect these cinder blocks support the brick cladding on the front face of the 2nd story. I would have to chip a small hole through the cinder blocks to gain access to the top of the steel plate and I beam. Once I do this, how can I get a hole through the two layers of steel? Will this have to be cut out with a torch, or by using a magnetic drill? Just trying to get some ideas here.
I could also just put the threaded rod through the ceiling joists above, but thought the steel I beam would be the best structural way to go.