Classes of Water: Rate of Evaporation

12/31/2021 (Permalink)

Flooding can cause different materials to absorb moisture differently.

When one of our Project Managers arrives at a job affected by the water, they will put each job into four different classes. These classes describe the potential rate of evaporation based on the amount of wet surface areas and porosity of materials affected. Each type requires a certain amount of equipment based on the estimated humidity load. 

Class 1: Minimal Water Means Slow Rate Evaporation 

• This class has little water absorption (less than 5%) in wet porous materials.
• Low evaporation materials such as concrete, plaster, and masonry will only be lightly affected and have absorbed minimum moisture. 

Class 2: Evaporation Progress at Significant Rates

• This class affects porous materials, between 5-40% of the surface areas such as floors, walls, and ceilings.
• This is when porous materials have absorbed a relatively significant amount of moisture; however, low evaporation materials have absorbed minimum moisture. 

Class 3: More Water Means Fastest Rate Evaporation

• This class is when water is more present than any other class and evaporation is fastest. 
• This is when 40% of the area surfaces being wet porous materials with low evaporation materials have absorbed minimum moisture. 

Class 4: Longest Drying Time

• This is when the water has saturated deeply into the material, and the moisture is being held or tapped as bound water.
• Excess water is bound to the molecules, and the only way to be released is by evaporation. It takes longer for materials to evaporate in this class.
• Low evaporation materials include hardwood, plaster, brick, and saturated concrete. 

Knowing the permeability of material can help our team understand the duration of time it will take to have material thoroughly dried.