I want a full basement under my new ranch style house and want the biggest possible open space with no posts. The maximum size would be 34'X32'. is it possible to have that big of a room without support posts?

Welcome the the Pool BDD. Glade to have you with us.

Possible. Almost anything is possible with money.

We have a bowling alley in our neighborhood the is 50 lanes long with no post. This is now common.

This would require industrial building techniques using steel beams and frames. My guess it would double the cost of conventional contruction.

Also, Engineered Lumber has become popular lately handling around then twice the load of standard lumber.

A quick check with an architect will tell you for sure.

32' should be possible and like WOW says, it will just cost you more. An architect will likely be required to prepare drawings but typically lumber yards will size trusses or custom engineered joists.

I kind of figured it would be more. What is the widest span that normal building techniques can cover. And yes, I'm planning to work with an architect. Thanks

Anything is possible, but FHA and building codes have standards.

You may want to consider a support down the middle. If I remember correctly, 2 x 10 joists placed 16" appart can support a house above if they are 16 feet long (or less). So your open spaces will be 34' x 16'. The support will be three 2 x 10's face to face with several vertical supports along the length.

If you want larger open spaces, you have to use larger pieces in the joists rated for greater weight.

Here's the real danger:

Over time, floors, walls and ceilings "bow". When they do, plaster begins to crack and you end up with a repair jobs. It's worth your while to meet spec when the opportunity is still there.