Capillary barrier underneath sill plate

I inspected a new home yesterday that was built on a concrete stem wall.
In most areas, a capillary barrier between the sill plate and the stem wall was not visible or not present.
In one spot it did look like there may have been a blue capillary barrier underneath the sill plate, albeit much smaller than the sill plate itself.

Please take a look at my pictures and tell me what you would say in the report.

" It appears that no sill plate gasket/ barrier was installed between the concrete foundation and the wooden sill plate. It also appears that the sill plate is not treated wood which may/or may not have been required at the time of construction. It is recommended that…"

Just from what I can see…


Looking at the pics I see nothing wrong, standard PT sill with sill sealer, it looks like sill sealer under the sill in some pics, what do you think? Maybe they used 2’‘x8’’ for the sill? the sill sealer is 5 1/2’’ wide.

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Your eyes are probably better than mine. I couldn’t see the PT. I guess I am used to seeing the green PT, but then again, depends on when it was constructed.

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If it is PT lumber and you saw some evidence of a capillary break, I would move on.


I was also looking at the grain in the wood, it looks like yellow pine. that is typically what PT is made from.

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It does look like blue sill sealer underneath the sill in some pics, but the sill plate is not green, and I’ve only seen green pressure treated sill plates before.

I don’t see pressure-treated wood. The home was brand new.


Thanks for the input. It’s interesting to know that PT wood can come in several different colors.

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Just a reminder, I believe with or without the capillary break, the sill plate atop the foundation must be PT. Of course, subject to local jurisdiction blah blah.


As Brian stated, PT is the most important aspect on the sill plate. It may look different based on your region, but here in the Southeast, we’ve or I have, been more accustomed to seeing the greenish/blueish colored. More than likely for identifying extra WDO treatment because of our termite issues…and not really sure on that, but know it’s PT.

I did some work a few years ago at a lumber yard that made PT lumber. They used different colored chemicals for different things. The wood that would end up having the greenish color was yellow pine and the chemical was a deep blue color. The bunks were banded together before entering the vacuum chamber on mini rail cars. The outermost boards had the blueish hue when dried, the innermost boards were light green. The whole operation was pretty neat to watch and learn about to say the least.


The regional differences are funny - In Oregon all the PT used for sill plates, etc. has hash marks where they inject the wood with chemicals. I don’t recognize any of that as being PT. I guess we have it easy. download

Some localities may require a termite shield.