Main Beam

[frogman68]

Our house is 20 feet wide and 40 feet wide single floor with full basement the main beam is a 6X6 with 2X8 joists (will have to sister 2X8's to most their is some big holes in some) we are planning on adding a level. Before we hire a engineer I would like to know what are some of our options to beef the main beam so we know when the engineer comes in we know if he is shady.

Thanks
Brian

[frogman68]

I forgot to mention the posts are 10 feet on center and are cinder block 8X8 's hollow.

[Rich]

There are several options.
1. Create a box beam around the existing main beam.
2. Put another 6x6 beneath the existing 6x6 - not sure what this would do to head clearance though.

Sistering the joists is acceptable. Looking at TrusJoist McMillans specification tables for a 20' wide home and column spacing of 10' (40 # LL + 20 # DL) you would need a 3.5" x 9.25" Microlam LVL beam. So Option 3 would be to support the existing floor and remove / replace with the above mentioned Microlam - again not sure what this does to head clearance.

Hope that helps.

[frogman68]

Thanks

Some construction guy told me he would put a steel plate on the bottom of the main beam then put lolly colums at the ends and the middle of the spans that seemed too easy.

Brian

[Rich]

That would probably work too.. I didn't even think of steel. I tend to stay with wood as much as possible - too traditional I guess. Do remember the engineering will need to be done in either case. Steel may be a bit more expensive also.