Structural drying in Cary, NC

How drying works

Wet materials dry when the water in them evaporates and that water vapor is removed before it can soak into something else. Three things control the speed: moving air across wet surfaces, dry air to absorb the moisture, and warmth. Restoration equipment manages all three on purpose.

Air movers alone are not enough. Blowing air across a wet room without dehumidification simply raises the humidity, and the moisture settles into furniture, drywall in the next room and anything else that is dry. Balanced drying pairs air movers with enough dehumidification to keep the air dry, inside a closed-off drying chamber.

The equipment

• Air movers are high-velocity fans that sit low and blow a sheet of air across floors and up walls. A common rule of thumb is roughly one for every 10 to 16 feet of wet wall, adjusted for the room.
• Low grain refrigerant (LGR) dehumidifiers can pull the air much drier than a household unit, which speeds evaporation from dense materials.
• Desiccant dehumidifiers dry the air with a moisture-absorbing wheel instead of cold coils, so they keep working in cool conditions and on specialty jobs.
• Wall cavity systems push dry air through small holes into the space inside the wall.
• Floor drying mats seal to hardwood and draw moisture up through the boards under suction.
• Air scrubbers with HEPA filters run alongside when there is any mold or contamination.

Drying walls without tearing them out

Drywall that got wet with clean water, is still firm and was reached quickly can usually be dried in place. The baseboards come off, small holes are drilled at the bottom of the wall behind where the trim sits, and dry air is directed into the cavity. Walls are opened instead when the drywall is sagging or crumbling, when the water was contaminated, when the insulation inside is soaked, or when a vinyl wallcovering or several coats of oil paint would trap the moisture. A flood cut, a straight cut a set height above the floor, is quicker to repair than ragged holes.

Hardwood floors, subfloors and cabinets

Wet hardwood cups as the bottom of each board swells more than the top. Drying mats and patience usually bring it back flatter than people expect, and it often needs several weeks to settle before anyone decides whether to sand, refinish or replace it. Sanding a cupped floor too early is how floors end up crowned once they finish drying. Under cabinets, the toe kicks are removed and air is directed into the space beneath. Particleboard that has already swollen does not shrink back, and is part of the repair rather than the drying. The warped floors page covers floor damage in more depth.

Daily monitoring and the dry standard

Drying is measured, not assumed. On each visit, readings are taken at the same marked points and recorded, along with the temperature and humidity inside and outside the drying chamber. Equipment is moved or added where readings are not dropping. Drying ends when wet materials match the dry standard, meaning the readings from the same material in an unaffected part of the house, and the final numbers become part of the record for your insurer.

Drying in a humid climate

Triangle summers work against drying. Outdoor air from May through September often carries more moisture than the drying chamber should, so windows stay closed and the dehumidifiers do the work. Opening the house to “air it out” on a muggy day usually adds water rather than removing it. In winter the heating system helps, as warm indoor air holds more moisture and carries it to the dehumidifiers.

What happens after drying

When the readings confirm the structure is dry, the equipment comes out and water damage repair can start. If any mold was found while the walls were open, it is handled through mold remediation before anything is closed up. Drying is usually billed by the day for each piece of equipment, which is one reason prompt extraction saves money; the water damage cost guide explains the rest.