Crawl space venting?

[Marcel R. Cyr]

Originally Posted by prussell

Well my site contractor told me that the red sticker meant it was OK, first time with this inspector, so I told him to forget the vent and back fill it.

I'm on the side of not venting.

Hey, Peter;

I always thought that

Red= stop

Yellow= proceed at your own risk.

Green,= Go for it and nail it.

Marcel

[Richard A. Hetzel]

You all may be on the side of "not venting", but unfortuately, the IRC requires that a crawl space either be mechanically conditioned or vented. There are no other choices.

I recently lived in a house where the owner had previously sealed the vents in the crawl space. A contractor went down there and came back out with his shirt soaking wet from touching the insulation, which was dripping with water. When the vents were re-opened, the moisture eventually left the crawl space. That is what the vents are there to do...allow moisture to leave when the humidity outside is low.

[Peter C. Russell]

Hi Marcel, thats what I thought to but the site contractor who has work in this town before says red means he's been there and the inspection is complete.

[Roy D. Cooke, Sr]

Originally Posted by Richard A. Hetzel

You all may be on the side of "not venting", but unfortuately, the IRC requires that a crawl space either be mechanically conditioned or vented. There are no other choices.

I recently lived in a house where the owner had previously sealed the vents in the crawl space. A contractor went down there and came back out with his shirt soaking wet from touching the insulation, which was dripping with water. When the vents were re-opened, the moisture eventually left the crawl space. That is what the vents are there to do...allow moisture to leave when the humidity outside is low.

And what happens in August when the CS is 55 degrees and the air out side is 90 degrees and 90 % humidity. ( every thing is wet )
More dirt around the out side and extend the down spouts makes a huge improvement.
Why not cover the dirt with plastic and keep the moisture in the ground.
.If it is that bad it needs a dehumidifier to control the Humidity.
This also tends to make the floor warmer and warm floor makes mama Happy . Mama is happy every body is happy.
Unfortunately is not always correct they are usually a few years behind new methods.
...... Cookie

[Marcel R. Cyr]

Originally Posted by Richard A. Hetzel

You all may be on the side of "not venting", but unfortuately, the IRC requires that a crawl space either be mechanically conditioned or vented. There are no other choices. If the AHJ's keep enforcing it, we won't have a choice.

I recently lived in a house where the owner had previously sealed the vents in the crawl space. A contractor went down there and came back out with his shirt soaking wet from touching the insulation, which was dripping with water. When the vents were re-opened, the moisture eventually left the crawl space. That is what the vents are there to do...allow moisture to leave when the humidity outside is low.

So what you are saying, is that when you have vents and the humidity is low outside, the moisture leaves, But then again when the moisture outside is high, it would loggically come right back in, wouldn't it?

That scenario, seems to indicate that the moisture barrier was not installed or not installed properly. A 100% vapor barrier would not allow that kind of moisture in an unvented crawl space unless it is coming from above. Which would mean that the interior of the house has a humidity level of in the upper 80's, then there would be other issues.

Marcel

[Peter C. Russell]

Most crawl space vents are the plastic type where it has a louver, the homeowner is supposed to open and close the vent as needed.......

Yeah right

[Marcel R. Cyr]

Originally Posted by prussell

Most crawl space vents are the plastic type where it has a louver, the homeowner is supposed to open and close the vent as needed.......

Yeah right

Peter, I think we all know that will not happen, and in reading the IRC, it appears that one might not be able to use an operable louvered vent for that purpose.
I might be incorrect, not sure. My logic tells me that if you are required to provide venting for crawl spaces, they should not be adjustable.

I am not a fan of vented crawlspaces either as long as it is done properly to control moisture and cold from infiltrating the house.

When one reads 408.2 and N1102.1.7 of the IRC it almost sounds ambiguous.

Marcel
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[Barry Adair]

Originally Posted by rcooke

Mama is happy every body is happy. Unfortunately is not always correct they are usually a few years behind new methods.
...... Cookie

I'm awaiting the day she catchs up with any of my methods.

[Peter C. Russell]

Marcel, in NH any code official can make any amendment to the code as they see fit, so when I go from town to town working it's pretty much a crap shoot, anyway his office was closed today, I'll see what happens tomorrow.

[Marcel R. Cyr]

Originally Posted by prussell

Marcel, in NH any code official can make any amendment to the code as they see fit, so when I go from town to town working it's pretty much a crap shoot, anyway his office was closed today, I'll see what happens tomorrow.

Peter; I work in a lot of different towns and cities in Maine also, and it appears that is the case also.

What is up with that, do you think these guys fabricate some of these amendments to suit their needs on that particulat day, or do you think that some of these towns have established some amendments to the current Codes that have been adopted?
Sometimes I wonder if it might not be the officer exercising his empowered duties. Now that would really piss me off if I were to find that out.

I would think that we might be on our guard and request and study the particular town or cities Code adoption, amendments to such and ordinances.

Just thinking off the top of my hat here. Do you think such things happen?

Marcel

[Peter C. Russell]

Originally Posted by mcyr

Peter; I work in a lot of different towns and cities in Maine also, and it appears that is the case also.

What is up with that, do you think these guys fabricate some of these amendments to suit their needs on that particulat day, or do you think that some of these towns have established some amendments to the current Codes that have been adopted?
Sometimes I wonder if it might not be the officer exercising his empowered duties. Now that would really piss me off if I were to find that out.

I would think that we might be on our guard and request and study the particular town or cities Code adoption, amendments to such and ordinances.

Just thinking off the top of my hat here. Do you think such things happen?

Marcel

Absolutely!!! I spoke to our state Senate committee hearing on this very subject and told them it's great to have the IRC as a state code but until the state can control it at the local level you have accomplished nothing.

[cbuell]

The IRC rquires venting or conditioning of the space. Conditioned doesn't mean that it has to be mechanically "vented"----it needs to "communicate" with the conditioned space. This communication can be passive or part of the forced air heating system. This may not always be essential----but it is still a good idea in most cases (at least according to the IRC Gods)

[Greg Veal]

Peter

In my area, a crawl space is defined as an enclosed area beneath the main floor of a building (Res. or Comm.), and that crawl area has an earthen/dirt floor area.
Venting of this type of area in my opinion is critical, and considered by some to be an art, if the ventilation is to be effective.

A crawl space "type" area with a finished/slab floor is considered a basement "technically", and does not require ventilation. Personally, if the area can be ventilated effectively, it won't hurt, and should be ventilated. Now, that's in my area of the country.

In NH, I'd have to think about it, due to your (assumed) extreme weather conditions. I'd maybe check with your local AHJ and/or your Dept. of Agriculture ( Entomology/Pest Div.) for advise.

Good Luck

[Peter C. Russell]

Thanks Greg, this is a point of contention that will be debated for as long as there are codes. Problem is, in NH we use the 2006 IRC code book, but the local inspector can supersede any code they want so as a builder we are at their discretion.

[Kenton H. Shepard, CMI]

It's really 2 issues...

The first is dealing with the inspector and codes. Unless you want to take him/them on, and that can mean anything between gently educating him or forcing a formal confrontation, you can give him what he wants, and when he's gone, do whatever you want.

The second is what's actually correct for the crawlspace, and that depends on the climate zone.