Insurance Claims Adjuster

The New Science of Structural Drying

As the science of structural drying has been evolving we have learned how to be more effective in our applications of equipment and energies in order to bring down the moisture content of any structure. The study of Psychrometry has opened up our understanding of the interaction of moisture, air and materials to the extent that we can work at manipulating the environment in such a way that it encourages the affected area to yield its moisture quickly and in a lot of cases, with less intrusive means than has been utilized in the past.

In the past a trial and error approach had lead us to conclusions and approaches that were okay for the time, but we realize now that we were overlooking some areas, and focusing too much on others. The traditional approach of tearing up the carpet and pad in Category One situations and floating the carpet to dry it down is a thing of the past. Often we ignored the structural drying needs in order to get the carpet dry.

The New Science of Drying

Simply stated, the new science of drying is the application of Psychrometry to any given water loss situation to ascertain how best to bring the moisture levels down effectively using the best technology and applications.

Stage One: Assessment and Planning

How would we approach a water loss today? We get the background data from the customer on their understanding of how the water loss occurred.

Gathering Background Information

We walk through their experience with them looking for key pieces of data that help us to understand:

Where did the water come from?
What kind of water was it (category of water) and what was its source?
How far did the water migrate?
How much of the structure was affected and what types of materials are wet?
How much water was released and over what period of time?
How long has the structure been affected?
Are there any immediate safety risks?
Have there been any water losses in the past?

Moisture Measurements

The source of the water loss must be eliminated first or drying will be impossible to achieve. We then take the data we have gleaned from the customer and begin using our instruments and training to create an analysis of the project as we understand it to this point.

We take relative humidity and temperaturereadings and apply psychrometric calculations in order to determine the specific humidity of the structure in various locations, including outside air.
We watch the relative humidity levels to monitor if we are below immediate danger levels (60 % RH is a warning number demanding immediate action. 69% RH is a critical level where the humidity must be reduced without hesitation. The dangers of mould appearing in the latter condition is very high)
We take moisture readings from various materials and in a multitude of locations to determine the extent of the water damage and the level of porosity we are dealing with in the materials we are going to dry.
This would also include getting dry standard measurements from other locations in the structure so we can use a comparison of measurements in finding out what is the normal environmental ecology of the structure. These are recorded in a grid map so that we will have base line information to determine how wet everything is and to have the information we need in choosing the right equipment for remediating.
We take measurements of the rooms to determine the lineal feet of the walls, dimensions which may include dead space areas, and cubic feet of space we are going to dry.

Development of a Drying Plan

This is where the new science of drying really begins to differentiate itself from the traditional method. In the new approach to applied structural drying there is a definitive rationale for the use of equipment based on specific goals which are measurable. A competent restorer is able to direct their efforts to achieve the desired effect and is able to monitor the outcomes. With the information gleaned so far the drying plan now begins to take shape. Questions that are asked in the process:

How do I create an effective drying chamber?
How many air movers do I use based on the category and class of water loss?
How many dehumidifiers are required to remove the moisture in the air when applied with the assigned air movers?
How do I position the equipment so that a vortex is created in the drying chamber?
How many air exchanges are required to be effective in utilizing the equipment to maximum efficiency?
Do we need to apply specialized drying equipment such as wall cavity injector systems and rescue mats?
Is it more cost effective to tear out some of the wall material rather than drying it down mechanically?
In some cases you even have to create a heating chamber as well for the project.

Stage Two: Water Removal

Extraction of the liquid water as quickly as possible is a top priority.
This step is critical because: 1. It serves to minimize potential damage, 2. It contains migrating water and helps prevent secondary damage, and 3. It dramatically reduces the drying time.
Extraction with a light wand is used only to remove the excess surface moisture and then a deep extraction method is utilized to remove the majority of the water from both carpet and pad. (It takes 1200 times more energy to transfer moisture to evaporation by mechanical means for removal rather using extraction as a method).
Special care must be taken in removing standing water due to the hydrostatic pressure that can be exerted on the external walls. Removing of the water too quickly can cause the pressure being exerted on the outside of the wall by the water column to collapse the wall inward.

Stage Three: Creating the Optimum Drying Environment

Creating A Drying Chamber

It is important to reduce the size of the area to be dried with a containment wall if at all possible so that the drying equipment will be used efficiently.

Proper Positioning of Equipment

In the set up of the equipment customers are often surprised that we set up our air movers around the outside of the room placed on an angle (which differs from 45 degrees to 15 degrees based on the type of air mover) facing the walls.
The science of structural drying has taught us that there is a boundary layer of air and moisture that extends just a few inches from the wall that acts as an insulator and hinders the walls desire to release moisture.
Our goal is to: 1. Create a pressure differential in that layer and, 2. to bring dry air into immediate communication with the wall.
If these goals are achieved properly, the outside structure will release its moisture due to fact that, with moisture, wet moves to dry and with air, high pressure moves to low pressure. By creating a vortex of air movement in the entire structure which moves consistently across these areas, we enhance the drying process.
Dehumidifiers are placed strategically in the air flow in order to promote the dry air that is moving within the vortex.
The type of dehumidifier used makes a huge difference on the ability to bring moisture levels down. Some dehumidifiers do not have the ability to create dry enough air (specific humidity levels) to create the moisture imbalance necessary to dry certain materials effectively. Dehumidifiers are rated on the AHAM (Association of Home Appliance Manufacturers) system. This measurement is the pints of water removed at 80 Degrees Fahrenheit, 60 % Relative Humidity for 24 Hours.
For Insurance Adjusters, a program like Xactimate by Xactware is invaluable in being able to understand the capacity of the equipment being utilized by a contractor and the associated cost. The contractor should be responsible and provide the capacity ratings when reporting on their drying project so that the adjuster can understand the rationale for the equipment placed in the project.

Stage Four: Documentation

As the drying process is taking place, the restoration professional and the customer should be asking the "Four Knows of Drying" questions throughout the project, beginning to end. Documentation aligned with clear drying goals and constant communication provides the best atmosphere for a positive engagement by everyone in the process.

"The success of each and every decision made during the restorative drying process depends on the information upon which the decision was based. The process of restorative drying involves a continuous cycle of information gathering, interpretation, decision making, validation and adjustment... There are four questions that summarize the information that must be obtained, documented and evaluated throughout the restorative drying process. When left unanswered, these questions are the source of the most common deficiencies in inspection and documentation. The four key questions, or 'knows' of drying are:

What's Wet?
How Wet Is It?
Is It Drying?
Is It Done?

Inspection, monitoring and documentation answer these four questions. A gap in this process will result in improper drying, additional water damage, and compromised cleanliness and integrity. Proper instruments and tools are a key ingredient to successful completion in the drying process.

Developments in technology, science, education and practice have all changed the landscape of the restoration drying industry. In particular, instrumentation technology has greatly advanced, offering more and better features for evaluating "What's wet" and "How wet it is." Ultimately, this has led to an increase in liability for those who have not kept up to date with current instrumentation technologies and changes in industry standards and procedures. The long-term effects of improper drying have become an area of interest to many attorneys across North America."

(New Guide to Restorative Drying, Dri-Eaz Education Series, pages 18-19)

The New Science of Drying is More Effective and More Cost Efficient and thus a Better Choice.