The Intrusive Moisture Test
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The Intrusive Moisture Test: You want to do WHAT to my walls?

Invade. Puncture. Penetrate. While these words do accurately describe how we plan to gain access to the materials we need to test for moisture, they also exaggerate the process and create unnecessary angst. We’re talking about holes just large enough to accommodate a common construction nail - it’s like comparing being sliced by a sword to being pricked with a pin. Trust us: this won’t hurt a bit.

Every inspection begins with a visual survey of the area(s) in question. Many factors, including the materials being tested, the latest climate conditions, the age of the home, and any available knowledge of the builder's construction techniques, play into our approach. We always use the least invasive method possible to accurately determine the condition of the structure. Once we know what we’re dealing with, we are able to decide which tools and testing approach – from the exterior or the interior – are most appropriate.


Exterior Probe Testing: Our #1

When evaluating exterior cladding, be it stucco or otherwise, probe testing from the exterior is our preferred method whenever possible. The majority of moisture issues stem from water caught between the sheathing and the cladding of the home on the exterior side of the wall cavity. Testing from the exterior puts us close to the action, without being limited by framing members, floors, ceilings, furniture, and other obstacles. The test holes we drill DO NOT harm the home or cause new sources of moisture entry; rather, they allow the inspector to measure the moisture content in and determine the condition of the sheathing, which is necessary to make a damage assessment. Damage assessment is an integral part of the moisture test and is critical to accurately determine the extent of remediation that may be needed on the home. Of course, we clean up when we’re done – the tiny holes are sealed with a color-matched caulk and become virtually indistinguishable to the untrained eye. Oh, and exterior testing does not breach the vapor barrier on the internal side of the wall cavity (we knew that would be your next question).


Interior Probe Testing: The Next Best Thing

Sometimes, it just isn’t practical to test from the exterior. Particularly when it comes to homes clad with brick, aluminum, steel or true stone, we have to rely on our backup plan: testing the sheathing from the interior. To do this, we measure the moisture content by inserting our test probes through the interior sheetrock, vapor barrier and the six-inch wall depth and into the sheathing. In addition to making damage assessment of the sheathing more difficult, interior testing limits access to most of the areas in a home that need to be tested. Regardless of the results, test holes are sealed and the information obtained will guide our next steps.

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Moisture & Structural Assessments in Residential and Commercial Properties


PHONE: 651.272.5552
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Minneapolis, St. Paul and surrounding Twin Cities areas throughout
Minnesota, Wisconsin, North Dakota, South Dakota and Iowa.



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