Foundation

[dnguyen]

What is/are the purpose of this type of paper below the foundation? It's in a fairly new construction. The grading around the house was poor and this "paper" was soaked with moisture. Was it intended as some sort of insulation? Any help would be appreciated.

[Dale Duffy]

Wow...and I thought I've seen it all---not so, damned if I know, have never seen anything like it, but will be interested when someone steps in and knows just what it could be used for.

If you don't have any luck Duc---

Post it on www.your-leaking-house.com I bet ole Mark Anderson will know if nobody knows here (which I'm sure will though).

[Wayne B. Wilson]

Termite food , with all that cement the need something to munch

[mnahrgang]

I don't remember the name of that type of foundation. But it's supposed to be that way.

The foundation walls are supported on pillars (on either end). When they are pored, the cardboard acts as a sacrificial support of the "beams" as they dry. Not a defect.

They use this type of foundation in areas that has extremely expansive soils. When the soil uplifts it doesn't push up on the foundation, but instead crushes the cardboard.

Duc, Where are you located? I've only seen pictures of this, never in person.

[Marcel R. Cyr]

What you are saying Mark is what they call Grade Beam Foundations,

and I believe you are correct in what you are saying. I just don't recognise the product.

A similar product shown here;
http://www.surevoid.com/surevoid_web...nter_tech.html

[Christopher Currins]

Originally Posted by mnahrgang

I don't remember the name of that type of foundation. But it's supposed to be that way.

The foundation walls are supported on pillars (on either end). When they are pored, the cardboard acts as a sacrificial support of the "beams" as they dry. Not a defect.

"Void Form" http://www.nachi.tv/episode63 Kenton describes this method at about 18 min. into video.

[dnguyen]

Thanks all for the input. It's the first time that I've experienced this as well. It looked very odd so I needed further clarification before I wrote up my report. I am located in California, San Jose. This home was located in Hayward. It was situated on a hillside thus the pillar answer made good sense. Moreover, the pillar would need to go very deep, at least 7' to daylight rule if I am not mistaken. Btw, the soil was normal, not the expansive type from what I evidenced. Thanks for the help!

[dnguyen]

I just did a little research based on Mr. Cyr's statement and this is what I found out.
" Re: Concrete pier and grade beam in Northeast

Everything we build is on pier and grade beam and has been for 30 years. Because of expansive soils, adobe in the flat lands but the engineers call the same for sandstone hillsides, we have to keep the grade beams 2" above ground. We install 2" Styrofoam and knock it out after the pour, or put 2" cardboard under the beams and let it rot out. My construction supplier who supplies all of my nails, rebar etc. delivers it along with the rebar, foundation bolts etc.

The hardest thing about this system is trying to explain to the customers that they can't dig out and put storage under the house, even if built on a steep hillside. The soils engineers want the water to be able to flow under the house unimpeded, but the customers always do dig out and we have a ton of problems with that. A good friend recently died and I've tried to explain it to his widow and she won't believe me, she believes everybody should be able to have a dry basement if they want to dig one out under their house, try telling that to a soils engineer!

http://forums.jlconline.com/forums/s...ad.php?t=32079

I am really confused now because according to the above statement because the soil engineers want the water to be able to flow under the house unimpeded.

I am trying to word this in the report for the client. Any advice?