Steel I-beam or not?

[Tom]

My wife and I are checking into the Patriot Torrey Pines with an extra 4ft. It will have a full basement. Our builder says that a steel beam is not recommended, since the house has been designed and engineered without. It would be an added, unnecessary expense. Any thoughts besides the number of posts to hold up the regular beams? Also any opinions on windows? The originals seem fine.
Thanks.

[trmimo]

A steel beam is not needed on a modular home because of the wood beam that runs down the center. The reason modular homes have more columns in the basement is because there is roof load at the marriage line. In a site built home the roof trusses are continuous across the house so roof load is carried at the sidewalls only. Because a modular home is divided in half, roof load is carried on the sidewalls and the marriage walls. If your objective is to reduce the number of basement posts, you would have to hire an engineer to recalculate the spacing with a steel beam added. The benefit of this will be limited, because if you note the load already imposed on the columns it is close to the rated capacity of most columns.

[Tom]

Thanks a bunch. Tom