For a new home slab, we work from your plans and soils report, and I'll go over the report's date with you early, because an old report can hold up the plans before anyone has dug. From there we lay out the footings and slab to the plans, and our crew digs the footing trenches to the depth the engineer calls for.
The base is where I won't give ground. It's hidden the day after the pour, so it's the first thing people want to trim when the budget gets tight. We dig out to firm soil and pack the subgrade, the dirt the slab sits on, in layers, because a base that's only raked level settles with the dirt and takes the slab with it.
Some jobs need more than a slab on grade. If your plans call for stem walls or a raised floor, our foundation installation work covers that. Small property owners who need paving poured around a new building can also talk to us about concrete parking lot building on the same visit.
If the slab is post-tensioned, we make sure you keep a record of it. One contractor's guide warns that cutting a stressed tendon releases its force all at once and can hurt people, and that any later opening needs the tendons found first by a qualified scanning contractor. Keep that record with the house papers for whoever cuts into the floor years from now.