Water Damage - Professional Instruments are Key to Proper Drying

There should be no guesswork when handling water loss

in a structure. There are many steps necessary to properly

inspect, measure, and track the drying process to insure

the restoration is complete. Using the proper instruments

is your best assurance of the highest quality results.

When first entering an area affected by moisture damage,

a professional restoration company will employ both

trained and experienced visual observation and professional

measuring instruments to determine the extent of the

migration of water. Time is critical. The longer water

remains in contact with building materials such as carpet,

wood, drywall, and insulation, the farther it spreads

and the more it is absorbed into those materials.

Measuring horizontal migration

Horizontal migration generally affects areas relating

to structural flooring including carpet and pad, and

hardwood floors. The amount of moisture that may have

migrated through carpet and into the padding below is

often not readily apparent through visual inspection

only. Padding has sponge-like properties that make it

more absorbent than carpet and allows water to spread

farther than it does on the surface of the carpeting.

A moisture sensor (especially designed for detecting

moisture in and under carpet) has metal probes that

penetrate through carpet and into padding. The moisture

sensor detects the presence of moisture (indicated by

an LED and/or an audible tone). It does not, however,

measure the quantity or how much water is present.

Measuring vertical migration

Once horizontal migration has been determined,

the next step is to find and map vertical migration.

Most structural building components are hygroscopic

meaning they absorb water at different rates

and in varying amounts. The density of a specific

material determines its rate of porosity. For

example gypsum drywall is much more porous than

the wood commonly used for structural lumber such

as 2x4 or 2x6 framing materials. And insulation

(within wall cavities) is more porous than gypsum

drywall.

A non-penetrating meter can be used to discover

vertical migration of water. This device uses

the principal of capacitance. When the sensor

is placed against a flat surface, pads on the

back of the instrument detect moisture to a depth

of approximately 5/8 of an inch. Placed against

wood, it reflects the content of water as an approximate

percentage. When used on other materials, it reflects

a reference number for moisture contained in that

material, and that reference number allows it

to be compared to similar materials that were

not affected by water damage.

When more detailed analysis is needed, a penetrating

moisture meter is used. This tool is calibrated

primarily for wood, but can be used on other materials

as well. With various attachments it can measure

moisture levels in gypsum drywall, wall paneling,

baseboard, interior cavity insulation, hardwood

flooring, concrete, etc. The penetrating meter

will cause minor damage when used, but those are

easily repaired and proper training will assure

the best way to use it to minimize its effects.

Measuring humidity

A thermo-hygrometer measures the temperature and relative

humidity present in any given environment. A professional

can then take that data and determine the specific humidity,

the actual amount of moisture in the air. When evaluating

a drying system, a professional must know, understand

and use the specific humidity to determine its effectiveness

in drying the air, and dry air is needed to achieve

dry structure and contents. Tracking and recording the

data from the thermo-hygrometer allows the restorer

to modify the drying system and take the necessary steps

to reduce the levels of moisture in the environment.

Determining the standard level of moisture

A professional will use the proper metering instruments

and equipment, and will determine the difference

between the measured moisture level and the dry

or normal state of building materials. Professional

restorers have a thorough understanding of the

normal moisture levels of most common building

components. Based on the difference between the

measured moisture levels and the normal states,

the professional determines the appropriate drying

times for each material. Areas of the structure

that were not affected by the water damage would

also be checked to establish the dry standard

if possible.

Mapping and recording

Consistent inspection and mapping of the affected

area will determine the extent of the water migration

(and evaporation) both horizontally and vertically.

Temperature and relative humidity measurement

readings should be recorded, both inside and outside

the structure. This monitoring should be performed

every 24 hours, at a minimum. During the drying

process, monitoring of both atmospheric and structural

moisture levels will show the daily drying process

until it is complete.