Water in air ducts is not much of a problem, except for the homeowner who is faced with it. Many homes are built on a slab and periodically the duct work that runs under the slab delivering heated and cooled air throughout the home will show evidence of moisture and in the worst cases, considerable standing water. Where does this water come from and what are the proven ways of solving the problem?
Although sub surface is most often a problem with homes built on a slab it can also be problematic for all homes; those with a crawl space and even those with a full basement. The problem has a great deal to do with the way water moves through the ground. If the slab sits on sandy soil such as that found in coastal areas such as Florida the water goes straight down through the sand, rarely will these homes have a problem with water in the air ducts. This however is not the case when it comes to homes that are built on soil with high clay content.
Water when it falls as rain easily passes through the topsoil; this is not highly compacted and contains a significant amount of voids. Below this top layer however, the soil gets progressively denser, this often stops the water from continuing straight down but as it has to go somewhere, it migrates in a horizontal direction.
Rarely will a house be built in a swale or hollow, however, as you get farther away from the house then there is the distinct possibility of land at a higher elevation. It may be hard to fathom but there can be several thousand gallons of water slowly moving in the direction of your home and it will easily find its way under the slab; as a result you end up with water in air ducts that are buried in a trench which is even lower than the top of the slab.
Water in air ducts can be a serious problem as it invites the growth of mold, the spores of which are quickly delivered around the home when the heating or cooling system is operating.
Once you have eliminated the source of the water in air ducts you are advised to coat the inside with a material that inhibits any further mold growth. You are invited to contact the Duct Armor dealer in your area for further information.
