Residential Foundation Question

[Kjogle]

I have a question about foundation walls for a new single-family residence located in southeast Pennsylvania. The soil type is in the category of GM, GC, SM, SM-SC and ML. The builder would like to use poured in place plain concrete foundation walls with f’c of 4000 Psi. The basement wall height is 8’10” and sits on a 10” x 20” continuous spread footing. A 4” diameter drain tile on 2” gravel base and 12” surround covered with sediment paper will be installed on the outside of the spread footing. The top of the wall is supported by the first floor joist system and the basement floor slab supports the bottom of the wall. The builder does not want to use rebar in the walls. The Seismic Design Category is C. When I am reading the IBC 2003, I see Table 1805.5(1), Plain Concrete allows walls with the above soils type and with a height of unbalanced backfill of 8’4” to be 10” thick. Am I interpreting this correctly?

 

[dicksewerrat]

You probably are. However, I wouldn't build a house on a cast in place wall with no rebar,even 10 inches. Just a little too paranoid to do it. The wall should also be tied to the footing with bars.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com