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jhk49
Crawl Space Dehumidification

I live in southwest Georgia. It is often humid in this area. My house is about 2000 sq.ft. and there is a crawl space under the house. The house was built during the late 70's. We have open vents around the perimeter of the crawl space and we also have a rather old plastic vapor barrier. I do not have a problem with water seeping into the crawl space as a result of flood or rain. I have a moisture problem presently under the house which appears to be due to a slow dripping water pipe. I will have this resolved next week.

My pest control company recommends that I install a new vapor barrier, encapsulate the crawl space, install a wireless humidity sensor and install a dehumidifier. The cost is about $2200, plus an annual $100 fee for maintenance of same.

I really have two (2) questions:

1. Since I believe that the main cause for the increased humidity in the crawl space to be the leaking water pipe, would it be just about as effective if I did everything BUT purchase/install the dehumidifier? I could use the wireless sensor to indicate if I have another problem with moisture under the house had started.

2. I have read that encapsulating/dehumidifying the crawl space can save as much as 20% in your HVAC bill annually. That sounds very high to me ....... does anyone else have experience on what the savings might be?

Much thanks for any help.
jhk49

ordjen
Re: Crawl Space Dehumidification

I have heard of crawl spaces being sealed off and brought into the "house envelope". The conditioned air from the furnace/air-conditioning is partially diverted into the crawl space, keeping it as dry as the house in general. In cold climates, this has the advantage of making the floor above "foot warm", making it more comfortable for those sitting above. It would also dry the air so that your cold water pipes should no longer sweat, although I would think it a good idea to slip the foam insulation over them anyhow.

This whole concept is kind of like crawl spaces in the Midwest where they are sealed and treated almost as if they are deep basements and part of the house envelope. In the Midwest the crawl space is usually as deep as the footings which must be about 4 feet deep to be below the frost level. Often the floors have cement slabs and are used for storage or the heating and air conditioning equipment are placed down there.

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