ICS Magazine

Wall Drying Units: Come Out, Come Out, Wherever You Are

March 2, 2007


In the early days of my carpet-cleaning career, responding to a call for water-damage restoration meant we would extract water from the carpet and perhaps place one or two sheet-metal air movers. Little or no thought was given to the moisture inside the wall cavity or to other wet surfaces.

Fast-forward three decades. Times change. Progress happens. Professional restorers have a number of excellent tools to help locate and remove moisture from all parts of a building. These tools have saved many a wall or hard wood floor from the dumpster. While eliminating the need for much structural repair, these tools are saving the insurance companies money and making the job of the restorer easier and more profitable.

Equipment is available that will deliver high-pressure air into wet wall cavities to speed up drying. Some wall-drying systems can also vacuum air out of walls. This feature is useful when there is concern that mold or other microorganisms inside the walls might be blown to other parts of the structure. You can now dry walls with a minimum of disruption. Nozzles that inject air into the walls require only easily repairable holes as small as ¼ inch.

Other wall drying systems use adapters to direct airflow from centrifugal air movers or axial fans into wall cavities. One tool adapts to fans, air scrubbers, dehumidifiers or other equipment with 12-, 14-, 16- or 18-inch outlets.

If you have not kept abreast of all the products on the market, you might be surprised at the special abilities of some units. One unit is able to deliver high volumes of air into 9 linear feet of wall. Many are flexible enough to even bend around corners! As many as five such units can be connected in a series using air supplied by just one air mover. When the job is done, the drying unit can be folded up to fit in a box about the size that would hold a 1-gallon jug.

Rather than working only with one specific fan, these special drying units can be attached to any standard air mover, axial fan, and even the heat exchange boxes of heat based drying systems.

This equipment will dry more than walls. Use them to direct air under cabinets, above ceilings and into other tight spaces. Many wall drying units including the one described above can also be used to accelerate the drying of hardwood floors by directing air underneath. A recent restoration job dramatically demonstrated this ability.



The hardwood was the floor of a nearby gym. The wood was installed over two layers of plywood with plastic and rubber disks underneath (to cushion the pounding feet of basketball players). A flood had left all layers of wood wet and puddles of water in the space below the wood.

After three weeks of drying efforts, where the in-house staff blew air over the surface of the wood, the moisture content of the floor was still way above normal and there was still standing water below the floor. Using the system discussed above, air from a heat-based drying system was directed under the hardwood and into the space below. Within three days moisture readings were back to normal, the cupping of the wood had subsided, and the floor was put into use without any need to refinish.

Water-damage restoration in the 21st century has advanced a great deal from drying in 1970. Cleaners and restorers of 2007 will benefit greatly by equipping themselves to take advantage of the latest tools.