Foundation installation in Bellevue NE - a solid base set below the frost line

The city's building official issues permits for structures built in Bellevue and within its two-mile jurisdiction, through the Permits and Inspections office. The city's list of exempt work names small sheds, not foundations, so check with the office before anything is dug. You can reach them at 402-293-3014, weekdays from 8 am to 4:30 pm, and when a permit applies, we take care of the application or walk you through it.

Bellevue's code sets the frost line at 42 inches below the outside grade, and foundations for buildings over 750 square feet or 10 feet tall have to reach below it unless they sit on solid rock or are otherwise protected from frost. Ground that freezes under a shallow footing can push it up, which is why the depth matters. We set the footing depth from that line when we lay out the job.

Yes, with some listed exceptions, state law requires new homes to include passive radon venting under basement and slab floors, which is a pipe path that lets soil gas under the floor vent out without a fan. The same law calls for a gasketed or otherwise sealed lid on any sump pit that's open to soil or serves drain tile loops. Building these features in during construction typically costs less than fixing a radon problem afterward, which is why I put them in the plan before we pour.

One author writing in a builders' trade magazine says waterproofing is a must-have if the basement is finished or might be someday, because it bridges the shrinkage cracks concrete gets as it dries. The same article says codes make dampproofing, a thinner coating that slows moisture, the minimum in well-draining soil and require waterproofing only where water tables are high. We settle this with you before the walls go up, since it's the hardest choice to change later.

We price each foundation after I've seen the lot, because the cost follows the size of the building, how deep the walls go and what gets built into them. A full basement runs more than a crawlspace, waterproofing runs more than dampproofing, and where the footing drain empties can add work, since tying into a storm sewer needs the city's approval. Call (402) 206-0944 and I'll go through those choices with you on site.

It runs in two parts, because the digging, pouring and curing come first and the backfill waits until the house is framed. Building guidance says backfilling should wait until the first floor is framed and sheathed or the walls are well braced, because packing dirt too early or running heavy equipment close can damage the walls. The permit and the weather move the first part, so we build both into the schedule we set with you.