Damp proofing

I've never heard of damp proofing the inside of anything. That's not going to work.

I was talking about code requirements for damp proofing its a little vague.

This message was edited 2 times. Last update was at 12/21/2014 11:19 AM EST

Cameron Anderson wrote:

Nathan wrote:It's interesting how Cameron and I live in virtually the same place when it comes to drainage issues and foundation types (and soil types and Radon levels and just about everything else), yet we have different views on it.

Both of us agree it's not necessary or code, but he says it's a good idea.

Cameron- I think they're cool, but just cool. If they're necessary, which I believe is rare, great, but otherwise a wasted expense that is usually sold dishonestly in my opinion.

Do you feel the same?

It depends on what you and I are referring to. Based on your exchange with Brad, we're not referring to the same thing. Damp proofing is just a moisture barrier coating on the exterior of the foundation walls. Based on Juan mentioning that, I assumed the drainage system he was referring to was a footing tile. At a minimum I think those should be present but an interior encapsulation or drainage system, while cool I agree, is well beyond what is needed to maintain a dry crawlspace.

I have two very dry crawlspaces because I maintain exterior drainage and both are covered with a simple plastic vapor barrier and ventilated well.

How many crawlspaces do you get in that are not very dry? I am sure that different regions call for different measures.

I would agree that there are a lot of snake oil salesmen/companies that push encapsulation as a be all end all. We have a few in our area that absolutely piss me off and we usually can beat their prices by 1/2. I run my company based on consumer education first and then we give them at least 3 or 4 options for solving their issues. I have a thousand before and after pictures and years of data that prove what we do not only works, but is great for the home.

http://www.thecrawlspacecompany.net

Juan:

Section 406 of the IRC is a bit vague, however, here's what it says: "Except where required by Section 406.2 to be waterproofed [high water table or severe soil-water conditions known to exist], foundation walls that retain earth and enclose interior spaces and floors below grade shall be dampproofed..." Generally from what I've seen in my inspections this does not include dirt crawlspaces that are not usable space - however, I've certainly seen many that could use help as I'm sure all of us have. Section 405 addresses foundation drains which is a different item. Hope this helps.

Thanks.

Juan Jimenez wrote:I've never heard of damp proofing the inside of anything. That's not going to work.

I was talking about code requirements for damp proofing its a little vague.

That's what I thought you were referring to.

Nate are you talking about a specialized interior system or just common exterior damp proofing coatings? I've never heard of salesmen selling an exterior dampproofing system.

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Juan, just curious. Damp proofing and drainage tiles would not be visible to us so what brought up your question? A phase inspection?

Mike Casey wrote:Juan:

Section 406 of the IRC is a bit vague, however, here's what it says: "Except where required by Section 406.2 to be waterproofed [high water table or severe soil-water conditions known to exist], foundation walls that retain earth and enclose interior spaces and floors below grade shall be dampproofed..." Generally from what I've seen in my inspections this does not include dirt crawlspaces that are not usable space - however, I've certainly seen many that could use help as I'm sure all of us have. Section 405 addresses foundation drains which is a different item. Hope this helps.

Thanks.

Thanks Mike

That's the code I was referring to and it is vague. One a code inspector forum some guys said they enforce damp proofing on all crawlspaces, some said only if the crawlspace ground is lower than the exterior grade, some said only if there was mechanical equipment in the crawlspace, and some said never. Even they can't agree.

It was a phase inspection and I told my clients that although it's generally not required, it is something they may want to consider and talk to the builder about. It's certainly cheaper to do it during the build as opposed to later.

Mike Casey wrote:Section 406 of the IRC is a bit vague, however, here's what it says: "Except where required by Section 406.2 to be waterproofed [high water table or severe soil-water conditions known to exist], foundation walls that retain earth and enclose interior spaces and floors below grade shall be dampproofed..." Generally from what I've seen in my inspections this does not include dirt crawlspaces that are not usable space.

That doesn't seem ambiguous to me. An enclosed interior space is specifically delineated along with a separate item "floors below grade". Every usable space below grade on the interior would fall into the category of "floors below grade". The crawlspace is one of the few items which would fit the other category "enclosed interior spaces" but is not a floor.

Any builder that would save a few bucks by not providing some moisture control at the exterior walls just because it is a crawl is not one I would ever recommend.

I have the IRC with the commentary which says "To minimize moisture in the form of water vapor from entering the below-ground spaces from the outside, dampproofing of the exterior foundation walls is necessary, unless waterproofing is required by section 406.2....." I agree it should be there for just about any house, however, I see many that are not as the AHJ did not require it. If I was doing a phase inspection I would certainly suggest it be installed.

Thanks.

bbrinke wrote:
How many crawlspaces do you get in that are not very dry? I am sure that different regions call for different measures.

I would agree that there are a lot of snake oil salesmen/companies that push encapsulation as a be all end all. We have a few in our area that absolutely piss me off and we usually can beat their prices by 1/2. I run my company based on consumer education first and then we give them at least 3 or 4 options for solving their issues. I have a thousand before and after pictures and years of data that prove what we do not only works, but is great for the home.

Nearly 100% of the crawlspaces I see have some level of moisture intrusion and most of the time part of it is coming through the walls.

Don't get me wrong, I think the type of systems like what you install are fantastic. I am thrilled when I find a home with one. The only point of my comment was to say that it doesn't take much to provide some basic moisture control in a crawlspace. If a contractor, like the one whose property Juan was inspecting, was was unwilling to do even the minimum, I would never give them the time of day. Any contractor with rudimentary knowledge of building science would know water is going to come through the foundation walls no matter how deep they are.

This message was edited 1 time. Last update was at 12/22/2014 11:32 PM EST

Mike Casey wrote:I have the IRC with the commentary which says "To minimize moisture in the form of water vapor from entering the below-ground spaces from the outside, dampproofing of the exterior foundation walls is necessary, unless waterproofing is required by section 406.2....." I agree it should be there for just about any house, however, I see many that are not as the AHJ did not require it. If I was doing a phase inspection I would certainly suggest it be installed.

Amen. All the more reason to have an inspector outside of the AHJ oversee your home's construction.