Expert: Dave Johnson - 11/14/2007

Question
Hi,
We have a Colorado Rocky Mtn. 24'x24' kit home cabin built on post and piers, 8' apart. It is built on a slope, east side at grade, west side 8' above grade. We're building a 19'x16' two story addition on south side with concrete poured walls and basement. We would like to add a foundation under the existing structure at the same time, for two reasons. One, to enable us to beef up floor joists, as there is some sagging, and two, critter control and insulating. We're getting lots of groans from excavating and foundation contractors, who are suggesting there must be an easier way to control for critters getting in there, and that structurally, the engineers have not asked for the foundation. Any suggestions?

Answer
Hi Jeanie,
Yes, I do have a suggestion. ICF's.!! (insulated concrete
forms) They are a wonderful product for under a jacked building, as well as for ANY foundation. They are easily used, develope an "r" value of 32-36 in most climates and
are ready for finish inside and out.
I would ask my contractor to look into this for you and you may also check out  www.nudura.com this is a product that we use here in Maine frequently and are pleased with the results.
I understand your builders being hesitant to jack a building and work under it...but its YOUR home and you should do what you want.
I hope this has helped, best of luck

Dave