Create a Conditioned Crawl Space
It’s widely thought that crawl space encapsulation is the the final step to create a conditioned crawl space, when actually it is not. The problems with crawl spaces comes from the environment under the house. The final step is to condition the air in the crawl space after you seal out the bad elements with the encapsulation process. Conditioning the space is either altering the dew point temperature, altering the air temperature or both. A crawl space dehumidifier is used to alter the dew point temperature and the homes heating/cooling system is used to alter the air temperature. To go out and purchase a crawl space dehumidifier, installed it and hope it will keep the crawl space dry without encapsulation is an empty hope.
In order for any crawl space dehumidifier to be able to lower the relative humidity (change the dew point temperature) in a crawl space, with any kind of success, there can not be an endless supply of moisture in the crawl space. It would be like trying to drain a swimming pool at one end while the garden hose is turned on full at the other end. Seems like a waste of time? Well, it is. Attempting to dehumidify a crawl space while ignoring the source of the moisture, the source being the open foundation vents and the open earth is a waste of time and money. Encapsulating your crawl space addressees both of these sources and allows the dehumidifier to successfully remove the moisture from the air and deliver the reason you bought the dehumidifier in the first place.
The same holds true with altering the air temperature using the homes heating/cooling system. I don’t have to tell you that it is impossible to heat a house in the winter if all the windows are open. I also don’t have to tell you the same is true with cooling a home in the summer with all the windows open. So, I think we would all agree that it is also impossible to alter the temperature in a crawl space with open foundation vents.
Budget is alway a concern, but remember if you save $500 and it does not work; did you really save $500? It often appears that encapsulating your crawl space is an “overkill”. Once you understand what you are truly attempting to accomplish it is easy to understand why anyone would take the time to do it properly.
There is more written on controlling Dew Point
There is more written on Conditioned Crawl Spaces