I read an interesting article by Bill Essler from Woodworking Network this week .
He wrote an article about a growing trend in mold growth underneath bathroom and kitchen cabinets during the final stages of construction.
This caught my attention because there’s still a lot of development in Florida and, as you know; it’s hot and muggy here.
In a report from Liberty Building Forensics Group, a leading building forensics firm that specializes in complex building moisture & mold problems, the problem is identified as coming from use of a new type of sound-deadening flooring seals.
Moisture and mold problems occur more often in expensive construction than in moderately priced construction.
In the report, a thickened gypsum based flooring was poured as an underlayment over a soundproofing mat in a hot, humid climate. The amount of moisture released to the cavity below the cabinets ultimately caused this area of the cabinets to become part of a microclimate that held moisture and resulted in mold damage so that the cabinets had to be removed as a part of the remediation efforts.
Noting the mold arises from the usually benign interaction between the HVAC systems, and sound attenuation design, Libery Building says the mold multiplies from a lack of sufficient drying (including dehumidification) in final stages of construction. Exacerbating the problem is the installation of enhanced floor sound barrier design. These factors are resulting in small micro-climates underneath cabinets is resulting in mold growth and moisture damage, according to the company.
Typical contract design documents should include a testing and monitoring program developed by the design team and adhered to by the construction contractor.
Tests of the building substrates (for example, gypsum board) performed before the interior finish is applied will consist primarily of in situ moisture level measurements. The contract design documents should include the unacceptable moisture level threshold.
The work involved in conducting a monitoring program is not extensive
and can be accomplished in two parts: monitoring the wall systems
before the interior finish is applied and monitoring after the finish is
After the interior finish has been applied to the wall system,
documentation and monitoring should be more intensive, especially if
the interior finish is impermeable. Because an impermeable finish will
trap moisture in the wall system and not allow it to dry, damage is
usually not apparent until mold odors or stains appear.
Substrate testing and monitoring typically involves placing a small
conductivity probe meter at staggered heights on all interior partitions of a room.
Since we don’t usually see all the stages of a building’s construction, I’d recommend engaging a home inspector prior to purchase on all buildings – old and new.
Black mold can be an insidious problem. If you discover black mold it’s best to engage a professional trained in its removal and containment.
Many DIY websites advise you to put bleach or vinegar on it. Don’t follow their advise. Bleach is made of water and water feeds mold. The following is from HGTV on how to remove mold.
How to Remove Black Mold
Removing black mold is a step-by-step process that requires patience, an investment in protective gear and black mold removal products, and, of course, the courage to brave dark, cramped spaces inhabited by toxic fungus.
First, you must remove the source of any moisture from the affected area. If any leaks or persistent condensation aren’t alleviated, the mold will likely reappear after removal.
Next, seal any doorways or other openings leading to other areas of the home, place heavy plastic over them, then seal the plastic in place with duct tape. If there are outdoor openings in the room, place an exhaust fan near them to help remove mold spores from the room.
Wear a respirator or a facemask rated for black mold spore protection, and cover arms, legs and hands to avoid contact with mold spores. Use soap and a sponge to remove visible mold. If the moldy area is dry, lightly spray with water, as this will reduce the incidence of airborne mold spores during cleaning.
Next, use commercial black mold removal products to disinfect the moldy areas, in addition to any adjacent areas. Place all sponges, equipment and other materials used in cleaning in a heavy-duty garbage bag, and if possible, remove the bag through a nearby exit as opposed to the main house, to avoid distributing mold spores.