Water Damage & Flooded Basement Restoration Services

Water Damage Categories and Classes

By the RestorationSOS Educational Staff

When water damage strikes a home or business, it generally goes a bit beyond everything just getting wet and needing to be dried out. In any case of water damage it is important to locate the source of the leak, for two major reasons. 1) It allows you to shut off the water and prevent any more from entering your property, and 2) it should give you an idea of the kind of water you are dealing with, if it contains contaminants, and how you should proceed with the restoration process.

One of the most important things to consider when assessing water damage is the affected materials. Different materials will respond differently to water exposure, so identifying what materials have been affected will help to determine the best course of action for restoring the property.

It is also important to consider the severity of the water damage, as well as the cause. For example, damage caused by severe weather or a broken water supply line will likely be more extensive than damage caused by a minor leak or a broken washing machine.

Commercial properties may also require additional consideration, as they often have more complex systems and equipment that may be impacted by water damage.

Hiring a professional for water damage restoration is crucial, as they will have the equipment and knowledge to properly assess and remediate the damage in any case, whether it is a residential or commercial property.

Water Damage Categories

Water is basically broken down into three categories:

Water damage can be caused by a variety of sources, such as broken water supply lines, washing machines, broken aquariums, toilet overflow, and standing water from floods or storms. It is important to note that the categories of water damage, such as Category 1, 2, and 3, are determined by the level of contamination in the water.

Category 1 Water - Also known as Clean Water, this category of water is sanitary water, with no contaminants at the source, and poses no major health risks to you or your family. You can drink it, wash with it, or (if it is steaming), you can inhale it safely. Most of the water that comes into your home will be Category 1 until it leaves its source, either a supply line, an appliance, or melting snow or rain. Category 1 water may also be referred to as "Clear Water."

Once clear water has left its source for a prolonged period of time, however, it can quickly become contaminated and deteriorate to Category 2 or 3. Water with a foul odor is a good indicator that it has been mixed with soil or other pollutants.

Category 2 Water - contains a degree of contaminant material and is unsafe for contact or consumption. This type of water is typically found as overflow water from appliances, toilets, aquariums, or water beds.

Like clean water, gray water (aka grey water) will also deteriorate and become foul smelling. This process will take less time to become toxic, and should be attended to as soon as possible.

Category 3 Water - Also known as Black Water, is grossly contaminated and may be highly toxic. It may contain raw sewage, pesticides, heavy metals, bacteria, viruses, or toxic organic substances. Black water will have a foul smell and likely contain harmful agents.

Unlike the first two categories, Black Water will have a foul smell and likely contain pathogenic, toxigenic, or other harmful agents.

Water Classes

Water is also divided into various classes that are determined by the rate of evaporation due to the type of materials affected, as well as the room or area that was flooded out. Proper determination of the class of water you are working with will help determine the type of equipment needed to properly remediate the problem and dry everything out as it should be.

Class 1 Water Damage - Slow Evaporation Rate: Water losses that affect only part of a room or area, or losses with lower permeance/porosity materials (e.g., plywood, particle board, structural wood, VCT, concrete). Little or no wet carpet or padding is present. Minimum moisture is absorbed by materials, releasing moisture slowly.

Class 2 Water Damage - Fast Evaporation Rate: Water losses that affect an entire room or carpet and cushion. Water has wicked up walls 12" - 24". There is moisture remaining in structural materials (e.g., plywood, particleboard, structural wood, concrete).

Class 3 Water Damage - Fastest Evaporation Rate: Water may have come from overhead. Ceilings, walls, insulation, carpet, cushion and sub-floor in the entire area are saturated.

Class 4 Water Damage - Specialty Drying Situations: These consist of wet materials with very low permeance/porosity (hardwood, plaster, brick, concrete, stone, crawlspace). Typically, there are deep pockets of saturation, which requires very low specific humidity.

In any case of water damage, it is crucial to have professional water damage restoration services on hand to properly address the issue. This is especially important when dealing with water supply lines, which can cause extensive damage to a property if not handled properly. It is important to be aware of the four classes of water and understand the different evaporation rates and materials affected in each class to ensure a successful restoration process.

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