Foundation Wall and Open Vents
Efflorescence is visible along the foundation walls of this crawl space, an indication of moisture infiltration. Moisture seeps through the porous cinderblock walls, bringing the salts and sediments to the surface. There are also open vents lining these foundation walls, allowing the outside air and moisture to freely enter the crawl space, becoming trapped and increasing relative humidity.
Flimsy Liner
The vapor barrier of this crawl space has been pushed aside and ripped in multiple places, exposing the dirt flooring. The earth's moisture rises from the earth/ground/soil and raises the relative humidity, which can lead to mold and mildew growth, condensation, and water puddles.
Radiant Barrier
A radiant barrier was used within the floor joists of this crawl space, instead of fiberglass insulation, which is more common in Richmond homes. The idea was to have the radiant barrier facing upwards in the floor joists to reflect the heat back into the home, but instead, the heat simply became trapped between the barrier and the subfloor. A pocket of heat was created under the subfloor where the wood would sweat, and mold would grow. The paperbacks of the radiant barrier were also subject to mold growth, and the barrier would be eaten away over time not only by mold but by mice and insects. The remaining pieces of the barrier are scattered on the floor, exposing the subfloor even further.
Mold and Mildew Growth
With so much excess moisture trapped in the crawl space, the relative humidity has risen contributing to the ideal environment for microbial growth. For mold and mildew to grow on organic materials, the relative humidity needs to be around or above 60% alongside warm temperatures. Musty odors and mold spores can rise into the home above and irritate those with allergies and asthma.
Mold Removal
The radiant barrier has been removed from the floor joists and the mold and mildew have been treated or remediated using an antimicrobial, called Shockwave. However, mold and mildew can grow back if the environment and relative humidity are not controlled.
CleanSpace Vapor Barrier
A heavy-duty CleanSpace vapor barrier has been installed over the dirt flooring of the crawl space. It gets wrapped around all piers, sealed with vinyl tape, and mechanically fastened to the foundation walls six to eight inches above outside grade. When properly sealed, this 7-layer polyethylene liner helps prevent the earth's moisture from rising into the crawl space and increasing the relative humidity.
Insulating Foundation Walls
The foundation walls of the crawl space have been insulated with closed-cell spray foam, with a two-inch viewing strip left uncovered for termite inspectors. This spray foam is applied at 1½ inches thick, making it an air barrier and vapor barrier. This helps to prevent any outside influence from affecting the relative humidity of the crawl space. The interior of the open vents lining these foundation walls have also been sealed with precisely cut foam board and sealed with can foam.
