This is another case of moisture is as moisture does.
My client's house is the third in a row built by the same builder. The two previous homes built have complaints by the homeowners that the roof is leaking.
My client's house is still under construction, but the roof and drywall is completed. They asked me to go by the house with Mighty Mo to see if there were any roof, wall or foundation leaks.
The only anomalies in the house were found on both sides of the master bathroom window.
These are odd spots for moisture.
Clearly it is a warm day, and the sun is shining on the windows and window sill. The lower portion of the window is slightly cooler because of a screen.
I took comparative temperature readings in two areas - Sp1 and Sp2 (in the upper left corner, somewhat hidden by the graphic).
These are both exterior walls.
There is a 6F temperature difference (called Delta T in thermography) between the two points. And the sun is not shining on either of those walls, so the comparison is instructive.
It is likely that moisture would account for the temperature difference. A moisture meter can determine if moisture is actually present.
And, on the gage in the photo, the moisture reading at Sp1 is 100%. The other side of the window was similar.
I had not been outdoors yet to see what could be causing this moisture issue.
Having a look shows exactly why.
The fiber cement siding has not yet been installed.
And gutters have not been installed either.
So, water is rushing down beside the shed roof over the window and directly onto the areas yet without siding.
Clearly siding and a gutter (with a proper kick-out flashing) should solve this problem.
But in the meantime we have an area on two exterior walls of the house that have gotten repeatedly wet over time.
This can be a problem as such repeated moisture is conducive to fungi, wood decay, and perhaps insulation damage.
These possibilities will have to be investigated, but not until AFTER the siding and gutter have been installed.
My recommendation: water is water and must be controlled. And when moisture evidence is found, the cause(s) must be determined. Unless the source can be identified a proper solution cannot be found. In this case the moisture sources were easily found, and the solutions evident. But without the thermal camera that moisture evidence indoors would have been difficult to find. It is impractical to touch a moisture meter over hundreds of locations in the house to see if there is moisture. But a quick sweep with a thermal camera can not only see temperature differences, but, as in this case, can measure them. The camera makes for a quick diagnosis. And the moisture meter makes for a quick determination.
Jay Markanich Real Estate Inspections, LLC
Based in Bristow, serving all of Northern Virginia.
Office (703) 330-6388 Cell (703) 585-7560