Well trained EIFS inspectors tend to be expensive because they must follow a strict test protocol and there is no way to determine beforehand how much time will be required to complete the assignment. Multiple stories, an abundance of windows, complex structural details, and significantly "wet" walls require a considerable time to test.  

The test will usually identify [1] the exact locations of moisture, [2] the moisture content of "wet" areas, and [2] specific recommendations concerning problem areas and/or remediation. 

Testing Methods

Initially, a non-invasive scanner is used identify potential areas of moisture and isolate which areas should be probed. The scanner will [1] significantly reduce the number of probes needed and, [2] identify more troubled areas than the probe alone.  Scanning devices do not read the exact moisture content of the wall; this is usually done by inserting probes into the exterior wall which then measure electrical conductivity.  A more invasive test is to cut a test section out of the side of the building and carefully inspect sheathing and support walls. 

The preferred scanning device to test for moisture within an EIFS wall is the Tramex* Wet Wall Scanner.  This instrument reads through fibre reinforced lamina and exterior insulation to locate moisture  present in the sheathing substrate and wood studs.  But it does not provide specific moisture content information and can be prone to "false positives". The scanner will sometimes register what it thinks is moisture but turns out to be something else.  For example, a house sheathed in foil-backed foam might read as moisture to the scanner.  Further, the device is not intrusive therefore, an inspector must make penetrations where the Tramex indicates measurable moisture.  This tool has reduced testing costs and increased the accuracy of tests considerably but its usefulness is limited since it does not detect the actual level of moisture as a percentage of material content. Since the repair/remediation protocol can change according to moisture content, the actual content must be determined. 

A Delmhorst* meter is often used to identify the source of moisture intrusion. The meter has a digital readout and three scales: [1] wood scale (6% - 40% moisture range) used on EIFS, wood studs, flooring, floor joists, lumber, external siding: [2] a reference scale (records from 0 to 100 on a relative basis) used on non-wood materials such as concrete, plaster, roofing, and insulation; and [3] gypsum scale (0.2% - 6%) for use on sheetrock.  It uses insulated contact pins to penetrate the cladding and determine the condition of the sheathing. The probes (electrodes with 6" pins) leave two holes that resemble a "snakebite".  After testing, the holes are sealed with caulk matched to the exterior color of the EIFS cladding.  

Electromagnetic wave technology is another procedure for testing moisture content however, it's readings can be biased by moisture closest to the surface and this procedure cannot always discriminate between surface and core moisture  

Infra-red testing is another method used to test for moisture.  The greatest disadvantage is that infra-red technology identifies only temperature differentials, not moisture which is inferred from the temperature differential.  One of the primary marketing advantages of infra-red inspections is that it is not invasive.  Unfortunately, failure to probe where scanner readouts indicate potential moisture negates the whole testing process. The inspector must determine whether decay is present in conjunction with moisture entrapment.

Probe meters are the only type of instrument on the market today that will alert inspectors to what is really happening beneath the EIFS finish coat.  To ensure accuracy, the [1]  electrode pins are best positioned parallel to the grain; [2] insulated pins should be driven to varying depths and checked, [3] non-insulated pins should be driven to their full depth and [4] the readings should adjusted to account for variations in electrode type, wood species, and temperature. 

Caveats

• Be cautious of the inspector who [1] merely reports that your home is "wet" or "dry", [2] does not meticulously inspect every section of the home, and/or [3] quotes a ridiculously low fee.  These are signs of a poorly trained or inexperienced inspector.

• Be wary of any inspector associated with a remediation contractor.  The potential arrangement creates the opportunity for skewing of results. 

• A diligent inspector should always probe "wet" walls.  The desire to minimize damage at the request of the homeowner should not interfere with a thorough test. Probe holes are easily concealed and virtually unseen when properly caulked.

• Be suspicious of inspectors who report moisture levels using only the Tramex Wet Wall Scanner.  The device cannot provide such a level of measurement precision and almost always requires further analysis.  Decay can only be located by probing through the EIFS wall cladding.  

**The Delmhorst Moisture Meter is manufactured by the Delmhorst Instrument  Company