Richard, What kind of building are you planning? Is it one or 2 story. Is it on a hill or level? Is it a residence or shop?
In many constructions here on the northern Calif. coast we use 2x6 for form material, and then use that after it is cleaned in the subfloor. It is a very efficient and easy way to go. Also you may install a "bond beam" down the centerline of the building to support, or a series of poured concrete piers to support floor loads. Both work well, and can be all poured at the same time. The form is stripped and the materials scraped and then re-used in the framing and such.
Block is a fine way to go also, and using any type of readily available floor joist system will work fine. The larger the floor joist the least amount of support.
Many ways to go. I use engineered trusses too, and you have to block those also. You buy the strand board that they make that matches the width of the engineered floor joist and use it for rime and block. I find standard lumber easier to work with than the engineered but that is just my choice. I have less splitting, and such with natural wood compared to manufactured boards.
john
I am looking at the probability of building a house soon using a wood floor truss system rather than a concrete slab. I've been looking at dozens of web sites for manufacturers and the one big thing I've noticed is, none of them are willing to talk prices online.
What I need is some kind of ballpark figure that will help me decide which way to go with this.
My plan is a simple 40x40 foot base. No basement. Just a crawlspace. The outer perimiter will be a simple 12 inch wide footer slab. Then a 3 course cinder block on that. Onto which the trusses will be mounted. Down the center, another foot wide footer slab and cinder block.
So I would have at most a 20 foot span. If necessary, footer slabs at the
10 foot marks.
24 inches on center so then I would need 40 trusses.
What's that gonna cost me for the trusses?