Moisture Problems in Crawlspaces Found During NJ Home Inspections

Many homes throughout the county are constructed on crawlspace foundations. A crawlspace foundation can be prone to dampness. Crawlspaces can be both vented and non-vented.

Moisture issues in some crawlspaces can be caused by high ground water or improper grading. The New Jersey home inspector should point out these issues. As warm air rises it brings from the crawlspace anything that is air born such as mold spores and high moisture. This is often referred to as the stack effect in homes.

In vented crawlspaces there should be sufficient cross ventilation from the installed vents. The home should be able to breathe. Having low decks or shrubs that block the vents make then ineffective. A crawlspace requires a minimum of 1 square foot of ventilation for every 150 square feet of crawlspace floor area. The vents need to be within 3 feet of the corners of the home to give the cross ventilation. For more information on mold and moisture controls please see New Jersey mold testing.

If the crawlspace has a dirt floor a vapor barrier should be installed in order to help keep moisture under control. A damaged or missing vapor barrier can be the cause of excess moisture inside the crawlspace. The moisture (vapor) barrier could possibly be damaged or loose. The vapor barrier should consist of 6 mil poly installed on the soil floor, overlapping and sealed at the columns and walls in the crawlspace. This type of installation should help control ground moisture vapors from going up into the house framing.

Poorly configured gutters or not having gutters at all can contribute to significant moisture problems by allowing water to pool and collect close to the exterior foundation walls of the home. As an example of the volumes of water we are talking about a one inch rain fall will allow for one thousand gallons or more of water pouring off the roof close to the foundation walls. There is a high probability that some of this water will end up in the crawlspace or basement. With proper gutters and downspouts that discharge away one can prevent water from pooling close to the foundation.

If the sub floor is insulated, the paper side (vapor barrier) should be installed towards the heated living area and put against the sub flooring. If it is reversed and it often is, it can trap moisture between the sub floor and the vapor barrier and hide moisture damage. If a non-vented crawlspace is properly installed, insulation will not be needed.

If a sump pump is installed in the crawlspace it should be located at the lowest point. The pump should be inspected and tested on a regular basis. A sump pump like the downspouts should discharge away from the foundation walls of the home.

Operating a dehumidifier is a very prudent idea when the crawlspace is non-vented, collection water from it needs to discharge into the waste pipes via a professionally configured trap. If not then regular trips to the crawlspace are needed to empty the dehumidifier

Is the home's crawlspace is well maintained, clean and accessible condition? The home inspector must be able to inspect it in full detail. You should also inspect it often for signs of moisture or mildew. The home inspector New Jersey will suggest any corrections that might be needed.

Don't underestimate the importance of your home's crawlspace and what you can do to prevent and cope with that all too similar moisture damage.