Class of Water Loss....

From  the IICRC S500 Standard and Reference Guide for Professional Water Damage restoration.


The term 'Class of water' also is the initial determination of the amount of water and the likely or anticipated rate of evaporation. It is used to determine the initial dehumidification capacity necessary to handle the potential amount of water that will be evaporated within an affected area.


Class 1  (least amount of water, absorption and evaporation) : Water losses that affect only part of a room or area, or larger areas containing materials that have absorbed minimal moisture. Little or no wet carpet and/or cushion is present.


Class 2  (large amount of water, absorption and evaporation): Water losses that affect at least an entire room of carpet and cushion (pad). Water has wicked up walls less than 24 inches. There is moisture remaining in structural materials; e.g., plywood, particle board, structural wood, VCT, concrete and substructure soil.


Class 3  (greatest amount of water, absorption and evaporation): Water may have come from overhead. Ceilings, walls, insulation, carpet, cushion and subfloor in virtually the entire area are saturated.


Class 4  (specialty drying situations): These consist of wet materials with very low permanence/porosity (e.g., hardwood, plaster, brick, concrete. light weight concrete and stone).  Typically, there are deep pockets of saturation, which require very low specific humidity. These types of losses may require longer drying times and special methods.


Determining the classes of water is an essential part of calculating the amount of initial dehumidification capacity necessary to handle the potential amount of water that will evaporate within the affected area, and air movement for the drying process.  Classes provide a point of reference to aid in the type, size and amount of equipment initially installed on a water damage restoration project. However, situations can arise that require adjustments to the type, amount and size of equipment Begin used during the drying process.




Water loss at your home or business, call us. Our crews are IICRC certified and trained to set up the best and most efficient drying program to restore your home back to pre-loss conditions.