Slab on grade banned for new construction in Charleston, South Carolina

Outside The Beltway
1

This is kind of interesting. Charleston, South Carolina has banned slab on grade for new construction. Because basements are not an option in that area, that leaves raised crawlspace construction, with the floor level typically raised 2 feet to 4 feet around the surrounding grade.

While slab on grade is generally favored by builders in warmer, coastal regions, it does tend to exacerbate flooding risks in a low level flood plain. A raised crawlspace keeps the home above the maximum flood level, particularly if builders keep the bottom of the structure at least 2 feet above grade and preferably higher.

Away from the coastal plain, crawlspace is the dominant foundation in both North and South Carolina.

Rather bold move by the city council, but given their unique concerns, it appears to be a justified move.

2

In Florida they truck in fill and raise the entire construction area by several feet above the surrounding grade.

3

So walkout basement is out of question. :rofl:

5 Likes
4

Which is pretty much part and parcel of the problem in Charleston. All the fill going in for slabs is compounding the problem.

5

Pretty much out of the question until you cross the fall line into the piedmont.

:smile:

Even then, basements are much rarer than in Pennsylvania. Mostly crawlspaces in the Carolinas.

6

wouldn’t slab on grade on a curve just raise everyone’s scores?