[nutshellml]

Afternoon All... New home owner and there is an addition to my split level that is on a concrete foundation slab (crawl space). During home inspection the inspector told me that I should vent the crawl space INTO the basement (there are two windows that I can easily do this) vs. closing the windows and opening the vents on the foundation wall and venting to the outside. I couldn't really find much literature or guidance on this, so any input is greatly appreciated.

 

[Windows on Wash]

How about a picture?

If you "vent" it into the conditioned space, you are treating it as part of the conditioned space and it will need insulation along the stem wall (exterior wall) as well as sealing at the rim joist.

Good way to go as long as there are no moisture issues in there and you can get some conditioned air in there.

 

[nutshellml]

How about a picture?

If you "vent" it into the conditioned space, you are treating it as part of the conditioned space and it will need insulation along the stem wall (exterior wall) as well as sealing at the rim joist.

Good way to go as long as there are no moisture issues in there and you can get some conditioned air in there.

Here are some pictures of the crawl space, showing the foundation vents and also the two former exterior windows which now open into the crawl space.

 

[Windows on Wash]

No brainer here in most cases. Insulate the outer (stem) wall and be done with it. Close up the vents and condition that space actively.

Take that fiberglass out of there at that point and have a nice, warm, dry storage space.

Where is the home?

You are, in effect, treating it like a basement wall.

http://buildingscience.com/documents/information-sheets/crawlspace-insulation

 

[nutshellml]

Take that fiberglass out of there at that point and have a nice, warm, dry storage space.

Where is the home?

You are, in effect, treating it like a basement wall.

http://buildingscience.com/documents/information-sheets/crawlspace-insulation

Northern NJ... Great article i was looking for literature about the issue. Can you confirm, basically - I would remove the insulation from the top of the crawl space, insulate the exterior concrete walls of the crawl space, and vent into the unfinished basement? And is there anything needed to do with the concrete floor?

 

[Windows on Wash]

Yes. Might want to push some forced air in there as well.

Hopefully they put a vapor barrier under the concrete and I would guess they did. Everything looks pretty well done there.

If they did, there isn't much to do there. Insulation would help on the floor, but it depends on how much you are worried about heat loss and you really don't want to leave that stuff exposed.

 

[carpdad]

Stop. Before you remove the floor insulation and start insulating the wall willy nilly, research and learn a lot more.
Crawl space conditioning depends on the conditioned space of the basement. What is the condition of your basement? Is it heated, damp smells, sump, etc? Crawl space may bring in more moisture. Crawl space has to be insulated the same as the wall, minimum, to keep the basement and the floor above not as cold. Is the basement insulated or at least kept warm enough? Your crawl space looks dry. I'd add insulation to the floor above. Landscape outside so the ground drains away from the foundation and roots can't come in. Keep the outside vents open.
Learn what it means to condition the crawl space. What is it for? Vapor only, temperature only or both? Building Science is a good site.

 

[Windows on Wash]

The link posted previously addresses the insulation levels. Hopefully they did put a vapor barrier under the concrete to help with the capillary moisture.

Grading and guttering are pivotal to keep water out of the wall/floor regardless.

The stem wall is so short that it will be cheaper and easier to insulate that stem wall as compared to properly insulating the flooring.

I agree with you that grading, gutters, and vapor barriers need to be checked as well as making sure you can get some forced air into that space.