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Tom Rollins
04-18-2008, 12:03 PM
I have never seen this before in my thirty years of doing HI. Can someone tell me what the purpose of the sheet metal covering the foundation is for (it was completely covering the slab all around the house). This house was built in 1978. This sheet metal is between the concrete slab and the first course of bricks, then there is two layers of Styrofoam approximately a half an inch thick up against the slab with a sheet of slate. Then the sheet metal is folded over to cover the Styrofoam and the slate. The owner said he has lived there for eight years and was told that this was to prevent termites from entering into the house. When the termite inspector was doing his inspection I asked him if he had ever seen this? His reply was that he had seen it in 1991 on a house In this neighborhood. I told him that the owner said the house behind this one had the same thing. In my report I said I could not view the foundation because it was not visible or accessible. I also recommend that the sheet metal be removed from around the foundation.

Tom Rollins

Nick Ostrowski
04-18-2008, 01:16 PM
Termite shield?

Aaron Miller
04-18-2008, 01:26 PM
Tom:

Must be some termite company's wet dream idea of how to rip off customers. The expanded polystyrene will only attract termites like a magnet and make it impossible to detect them. I suppose the metal is just for effect.

Good call telling them to lose it.

Aaron:D

Steve Lowery
04-18-2008, 01:58 PM
Somewhere in the distant past (anything over about a day & a half) I remember reading about a system where the slab is poured over foam which is also wrapped around the footing down far enough to get below the frost line. This was to provide a "warm' slab. Sometimes in con -junction w/ hydronics. The termites tended to come up between the foam & 'crete and no one knew until things got ugly.

Various things were tried including the use of ditomaceous earth dug in around the footing. I don't think I've heard about this system in a long time (anything over a week).

The older I get the better I was.

Steve Lowery
04-18-2008, 02:08 PM
Ahh jeez. I drifted and only realized when I saw my reply.

The Metal (and I guess in this case the slate) was to protect the foam from damage. The metal was also recommended in the past as a termite barrier. The little b*****ds are supposed to not build their tubes on the metal (electrolytic something or other) or maybe they just couldn't get around the edge.

I have not read or heard of anything to prove or disprove the contention.

Jim Robinson
04-18-2008, 03:22 PM
Tom, why did you think they should remove the metal? I don't see what harm it is doing, and I would think that removing it would open up the area to intrusion by moisture and/or termites. It does remind me of some of the flashing on columns in the crawl space that I think were designed to keep termites from crawling up the concrete onto the wood. Did the sill plate rest directly onto the metal, or couldn't you see that anywhere.

Matt Fellman
04-18-2008, 10:13 PM
I've similar flashing in various installations.... I don't even want to offer a guess as to the funtion in this case but it looks like the level surface is actually sloping back towards the building which can't be good.

Terry Beck
05-29-2008, 05:05 PM
If I see metal sheeting around a foundation, I automatically assume that it is covering some sort of foam covered foundations (Insulated Concrete Forms, Structural Insulated Panels, etc). The stryofoam or rigid foam panels deteriorate when exposed to UV light, so need some sort of protection (besides the idea about termites).

If I see metal sheeting in homes built in the 60's-80's, I suspect a Permanent Wood foundation (usually a crawl or basement).

If I see metal sheeting covering homes built in late 1800's to 1920s, then I suspect it covering a rock and mortar foundation. (and it may have experienced some deteriorations).

So, see, metal sheeting does serve a purpose.

James Duffin
05-29-2008, 05:38 PM
It looks to me that the purpose of the flashing is to help keep water from getting to the wood structure behind the brick.

Robert Dalga
05-30-2008, 05:44 AM
Tom,
I also don't understand why you recommend that they remove the sheet metal. You probably should correct that response in an addendum report.

Rick Hurst
05-30-2008, 03:52 PM
?

Where is the water going that collects on the sheet metal?

Looks like it is sloped back towards the brick veneer and could be a source for water penetration.

rick

Mike Schulz
06-03-2008, 04:43 PM
It looks to me to be a cap flashing because the slab is offset to the wall. I bet you it's a "Z" shaped flashing and it turns up under the brick on the framing. The brick veneer needs a drainage plane, flashings and there should of been weep holes at the flashings.
Asking to remove it before you know why it is there can open another can of worms for you down the road. Let's say they remove it and a couple years later they get rotted sills etc. How can you justify that in court saying "well it just did not look like it belong there".

If it was me I think I would of just let the termite guy worry about his stuff and I would of said recommend checking with current owner of why it was installed or examined closer to try and identify why.

Mike Schulz
06-03-2008, 04:47 PM
Looking closer at the pictures I do see the weep holes along the first course of brick. And Because the foundation and wall is offset that is why it looks wierd to you.
That flashing needs to be there. Better inform your clients.