TOPIC: Moisture mystery

Inspected a single level house yesterday and found moisture in the ceiling about 8 feet in from the front wall.  The moisture was about 4 feet in diameter. Saw it on my thermal camera and the paint was flaking.  Also moisture meter buried the needle at that location, but other areas of the ceiling the needle didn't move.  Went to the roof and all looked good.  Attic; no moisture staining, leaking and the insulation looked fine.  No pipes running through there as all the plumping is on the back of the house.  Here are the pictures (thermal, roof and attic).  Any thoughts?

Remove all the insulation from over the damp patch. This should allow you to make an informed assessment.
Also, the moisture stain as indicated by the thermal image is very symmetrical which is unusual for most leaks.

I'll tell you one thing that it is...

It is a perfect example as to why a Flir i7  should not be used for building applications.
Sorry!

Here is what your scan really looks like:


It appears to be associated with a thermal bypass.

The sensitivity and spatial resolution of the camera is insufficient to confirm this but there is no other visible evidence to the contrary.

Where are the HVAC air-conditioning registers located (if there are any)?

Removal of the insulation may not necessarily disclose anything either.

The symmetrical shape is likely associated with a sheetrock panel joint. Are we 4 feet from the wall?

Hi David

What thermal camera are you using.

Plus, Doug said in his post

Also moisture meter buried the needle at that location, but other areas of the ceiling the needle didn't move.

What readings did you get from the moisture meter, what moisture meter where you using and did you take moisture readings from both sides of the damp ceiling.

A modified Flir T 400 and other 320 x 240 resolution cameras specifically for building use.

Using a moisture meter verifies the issue but does not identify the source of the problem.


BTW: I am not condemning Doug's use of that camera, he would be a lot more in the dark without it!

I simply want to illustrate to any of you that are getting into this business, what you are up against and what you should be considering when making your initial investment.

The camera would work, but as you can see thermal tuning and thermal scan manipulation is much more effective in determining the source of the problem than running a thermal camera in the automatic mode (which some cameras are only capable of).