Adjuster Resources

Before you can address a water damage you must first understand what type of water damage you are dealing with. There are three categories of water damage, which can then be divided into four classes. The category of water loss determines what you dry; the class determines how you dry it.

Category 1 – Clean water

Water originating from either a broken pipe or a burst supply line to an appliance.
May deteriorate in cleanliness when in contact with structural surfaces and content materials.
The only Category of water loss where you are able to utilize in place drying.
Statistically, there is no such thing as clean water, as once the water comes into contact with carpet, it is gray water.

Category 2 – Gray water

Water originating from an appliance discharge, or from inside an appliance.
Water containing a significant degree of chemical, biological and/or physical contamination.
Cushion (carpet pad) must be removed and replaced.
Carpet that is saved must be cleaned with hot water extraction.
Clean water becomes gray water after 72 hours.

Category 3 – Black water

Grossly unsanitary water containing pathogenic agents arising from sewage or other contaminated water sources.
Water originating from a source that poses substantial threat to human health.
Carpet and cushion must be removed and disposed. All porous materials must be disposed of.
Gray water becomes black water after 72 hours.

Class 1 – Slow rate of evaporation

Small size water loss.
Water losses that affect only part of a room or area.
Losses with low-permeance/porosity materials (e.g. plywood, particleboard, structural wood, VCT, concrete).
Little or no wet carpet and/or cushion is present.
Minimum moisture is absorbed by materials, which release that moisture slowly.
On hot dry days this class is an ideal candidate for open system dehumidification.

Class 2 – Fast rate of evaporation

Medium size water loss.
Water losses that affect the entire room of carpet and cushion.
Water has wicked up walls less than 24 inches.
There is moisture remaining in the structural materials (e.g. plywood, particleboard, structural wood, VCT, concrete).

Class 3 – Fastest rate of evaporation

Large size water loss.
Carpet and pad with water from coming from above or water wicking more than 24” up walls.
Ceilings, walls, insulation, carpet, cushion and subfloor in virtually the entire area are saturated.

Class 4 – Specialty drying situations, focus on bound water

Involves wet materials that are very low permeance/porosity (e.g. hardwoods, subfloors, plaster, brick, concrete, stone, crawlspaces).
Typically there are deep pockets of saturation that normally require very low specific humidity.
In laymen's terms a class four water loss involves drying hardwood flooring, concrete or some such material.

Drying Methods

There are two main drying methods that are utilized by most disaster restoration firms. Which type of method is used is determined by cost, damage and contamination.

Disruptive Methods (Removal, Injection, Perforation)

Floating carpet.
Removal of cushion.
Inter air-drying systems.
Removal of low permeance materials.
Perforation of low permeance materials.

Aggressive Methods (Humidity, Airflow, Temp)

In-place drying (Baseboards are usually dried in place with low specific humidity and dry airflow, MDF is always pulled).
When to use in place drying: clean water, wet less than 72 hours, when drying cushion/underlay won’t cause additional damage and there is adequate dehumidification. Certain new styles of carpet seem to delaminate immediately after getting wet; in these types of situations in place drying is very effective. In a case where wet underlayment needs to be removed from under this type of carpet, we can dry the carpet prior to removing the underlayment.
Benefits of drying aggressively: fewer repairs are needed, save millions on carpet and baseboard, jobs are completed faster.

Combining methods may be necessary depending on the combination of materials within the loss area.

General Equipment Rules of Thumb

Amount of equipment is determined by the class of water loss and drying method used. Type of equipment is based on material types and existing indoor and outdoor humidity and temperatures. Equipment placement is based upon the drying method used.

Air Mover –

Class 1 – Ensure air movement across all wet surfaces (as little as one per 300 sq. ft. to one per 150 sq. ft.)
Class 2 – One air mover per 50-60 sq. ft.
Class 3 – One air mover per 50-60 sq. ft.

Regardless of class, ensure air movement across all wet surfaces.

Air Mover Installation –

Clockwise rotation at 45 angle touching wall.
Inlet towards wall.
Turbulence air flow.
One for every 10-14 linear feet of wall space (more applicable for in place drying)

Dehumidifier –

Determine cubic feet first (cubic feet = length x width x height) When determining amount of dehumidification necessary, you must first consider cubic feet in the affected area.
Types of dehumidifiers
- Refrigerant and standard refrigerant (Works to 35 degrees, 35-40% relative humidity out)
- Low Grain Refrigerants (Works to 28-33 degrees, 20% relative humidity out)
- Desiccant Dehumidifiers (Works to below freezing, 0% relative humidity out)

Determine type of water loss
- Class 1 – no carpet and pad
- Class 2 – carpet and pad
- Class 3 – Carpet and pad with water from above or water more than 24“ up walls
- Class 4 – Specialty focus on bound water
Refrigerants: Cubic feet/Flow chart = AHAM pints necessary
Desiccants: AEH x Cubic feet/60 = CFM of process air necessary
General rule: Large room-One refrigerant dehumidifier per 4 air movers. Multiple Small Rooms-one refrigerant dehumidifier per 2 air movers.
Pint Removal: CFM x Grain Depression 71 = pints

Things to Watch For

Length of time equipment is in the home

There should be enough equipment in the home to insure that it is dry in approximately three days.
Class 3 and 4 water losses can frequently take four to five days to dry out.
Class 4 water losses are the only water losses that should go beyond the four to five day point.
You have 72 hours to mitigate, if you are not half way done drying by day two you need to reevaluate your drying process.
No marked signes of improvement by day two means you either need more equipment or more demolition.

Types of equipment in the home

Extra large or desiccant dehumidifiers
- Used typically for class 3 and 4 water losses only.
- In a class 4 water loss, conventional dehumidifiers don't do anything past day one.
Air Scrubbers
- For water mitigation purposes air scrubbers are generally reserved for category 3 water losses only.
- This may change when the IICRC releases a revised edition of the S500.
If any vendor cannot explain and prove through documentation why any piece of equipment was needed they should not be compensated.