Moisture meter question?

Hello everyone,

We just recently moved into the house we bought 5 months ago.( house was built 8 years ago). Before we bought the place we had it inspected by a top inspector in our area and he was excellent. The stand up shower we have is made with Travertine stone tiles all throughout. I notice a musty like smell every time I take a shower( it seems to be coming from the tiles). There is no smell when the shower is not in use, it is only when I am in there and the water is on. It may be the stone tiles themselves, I am not sure. We use to have just ceramic tiles where we use to live, so the stone tile is new to us. We clean the shower weekly using just borax and hot water. I am super sensitive to chemicals so I try and use more non-VOC and low odor products.

We went out and bought a moisture meter ( By General). We wanted to make sure there was no moisture behind the tiles. Now with moisture meters, how exactly do you determine what is to high? Also, is there anything that can cause the reading to go high besides water/moisture in certain areas of the shower? When checking the shower bench inside the shower, it showed 100% reading on the meter, in every spot we put it on that bench. Also, in our downstairs basement shower, the reading on the floor of the shower was also at 100%, again, that was in every place we checked on the floor of the shower. I am just wondering if anything else( concrete, metal) could make this reading be this high? I know when we had our inspector out here he checked everything. He also did moisture checks and they were okay at that time, but again, I was not in there when he was checking. Just wanted your opinions. Thank you much.

Moisture meters will read 100% if in contact with metal. If your inspector did not take a pic of his moisture meter you have no way confirming how he tested the shower pan. Here are the pic of one I found recently and how I test for leaks

Thanks for the reply. He did a few things. I know he ran water and filled things up to see if there was any leaking. He also did the same with the tub. I will have to go back and look at the inspection pictures to see if he actually took pictures of the moisture meter. I know he said at the time all moisture checks were good. So I am not sure if maybe the readings I am getting are that high because there is something underneath it like metal or concrete or something.

Also, is it normal to find low amounts of moisture in areas where there are piped behind the tiles( from normal condensation on pipes)?

water opens sinuses & warm water/steam will exacerbate odors
try washing shower with a regular Dawn dish soap without amonia and Comet runny mixture, rubbed on with sponge & leave for 15 minutes or more then rinse thoroughly
if your not trained/experienced expect false positives with comparatively cheapo meter

Thank you, that makes sense. We tried washing the shower with dawn( I am super sensitive and cannot handle the perfume odor that dawn dish soap has). Could I use an different kind of dish soap that maybe is less smelly along with Comet? Would that work?

To start with, lets try to perceive this; moisture meters do not detect moisture. They measure *** effects of moisture***.

There are basically four types of testers: conductance, density, thermal and nuclear.

Moisture conducts electricity: Pin meters measure conductance across the pins. Moisture increases conductivity.

Moisture increases density: Ultrasound meters compare wet vs dry density.

Thermal: Water causes changes in temperature (both warmer and/or cooler). Thermal Imagers measure this energy change.

Nuclear: detects nitrogen. A change in nitrogen concentration occurs due to moisture.

Next: *Where are you measuring? *A pin tester measures the surface conductivity (not inside the wall unless you drill holes). Ultrasound can only detect to a short depth. Sheetrock and stone do not allow the same depth readings (can’t measure behind the tile). Thermal can’t see through water. Nuclear measures nitrogen which is everywhere. These devices are calibrated for the material testing they were designed for.

Do you have the right tool: No.
You can’t afford Thermal or Nuclear.
If you use the others, you need to drill or tear something out and is no longer non-distructive testing.

Hire a professional. You need a degree in physics or thermodynamics, not just the equipment to find out what your looking for.

Thank you for your response. Where would I find someone who is knowledgeable about this that I can hire to check things out? What type of person would I need to look for?

That is funny I have no degree and find leaking shower pans all the time???

Some people just ask for the time of day not how to build a watch;-):wink:

Like hell you don’t!

I don’t know if I’m reading this OP correctly, but it sounds like you’re trying to take moisture meter readings through a stone shower wall after using the shower.

I’ll see anything where they trying to find a leaking shower pan.

They are looking for why they have high readings at the floor and bench. This would be density changes would you not agree? This is also a horizontal versus a vertical surface.

The problem I am trying to figure out is why certain areas in the shower are showing higher moisture readings( i.e the whole bench in master bath measured at 100% on the moisture meter, and the basement shower floor showed 100% moisture on the meter. It was not one area of the floor, it was the whole floor. That is why I was wondering it this measurement means there is actual moisture or is it giving a false positive for another reason( possible metal or concrete the meter is picking up)?

I think my pic pretty well explained how to search for a shower pan leak. I just give the time of day I don’t build watches:D:D:D:D

now boys…

travertine tile will hold a lot of moisture and is really not a great choice for a shower wall or floor.

I agree. I did not even think about the tiles when we bought the house. Why would they even put travertine tiles in showers? It seems like that is the thing these days. I miss the good old ceramic tiles we use to have! Much easier to clean.

**Travertine tiles is a very porous material the will absorb any liquid that is in contact. If it is installed on the floor the liquid will follow to the bottom and obviously mildew and mold will grow specifically if it is installed on a shower stall on a enclosed shower space. Many shampoos, soap ordetergent may contend different types of scent + body oils +……… can deposit in the bottom of the tiles. Therefore you may have a crust of ……… that when incontact with water again may develop odors for the mildew or mold…… I will dry the **** out of it and roll a solvent base sealer and seal the hell out of itto covet the holes. Or replace the dam travertine tiles with ceramic tiles and be done with it. **

You do not need to have a physics or thermodynamics degree. Just with a simple degree in Mechanical Engineer will do…….

Thank you for the reply. So why would they even use travertine if water goes all the way through to the bottom? The bottom tiles seem a bit more smooth so maybe they were polished or sealed at some point. We cannot really afford to rip it all out and redo it at this point. Do you think mold is growing behind all the tiles then because the are stone? That would be awful. I tried using the moisture meter on the closet wall since that would be where the back side of the shower wall would be and there was hardly any moisture at all on that wall. Would that be a good thing?

Lastly, is there any sealant that is very low odor( No VOC’s) that I can use to seal it? I am super sensitive to VOC’s and have allergies to them. Thanks again for the reply.

because people think it looks nice and stone and tile people want to make a sale and most of them don’t have a clue what they are selling…

It would if that wall was wet because the leak is big enough.

It is not likely you can measure any deeper than the sheetrock on that wall. Depends on your equipment.

Sounds like you have a significant sensitivity problem.
It is not likely you can kill mold with shampoo. Which is more tolerable, the smell or chemicals?

Nice work ole man!! now get back up on that roof!!

I did I was on this one yesterday