Basement walls

[jterry]

I was in a home the other day with a realtor, and was a little confused with the basement walls. The hole basement looked like Styrofoam blocks that where tied togeather. I didn't have my camera with me when the realtor called. Any help on what it is and how it holds up.

[Raymond N. Newman]

You ar most likely taking about insulated concrete forms (ICF's). They ought to be filled with concrete and rebar.

They come in three main types,

block forms, plank forms or panel forms and form the concrete also in three different ways.

Flatt walls are essentially similar to a traditional formed wall. Grid walls use less concrete then flat walls. Post-and-beam walls use the least concrete.

[jterry]

Thanks for the info.

[Kenton H. Shepard, CMI]

Some types of ICF systems have been known to have problems concerning concrete consolidation. You don't have to determine whether what you're looking at is the type which has problems, that would be a specialty inspection, but it's a good disclaimer to include when reporting on ICF walls.

[Michael A. Gillingham]

What Kenton said is absolutely true. I have run into ICF foundation walls that have had moisture intrusion problems. As to the exact cause I can only speculate without getting destructive or performing a specialty inspection. Best guess is that the guys on the pour did not adequately vibrate causing a consolidation issue. Proper placement, reinforcement and cosolidation is key when it comes to concrete.