When Is A Drain Leak Not A Drain Leak? Well, When It's A Wall Leak.

So, when is a drain leak not a drain leak?  Well, when it's a wall leak.

I was called to investigate a drain leak.  In addition to other things.  But this one was a biggie to this homeowner.

The floor outside the master bathroom shower, a bamboo floor, was staining, bulging a bit, and decidedly wet after showers.

Indeed, the floor did register over 30% moisture on the moisture meter.

The colored gauge indicates wood moisture.  Wood is considered saturated at 28% moisture, so the gauge only goes to 30%.  When the needle jumps to 30%, as it did in this case, the moisture content is higher.   And we know the wood is saturated.

However, the wall registered 100% moisture too!

Starting about 18" off the floor the wall registered moisture only in a particular area.

On this meter the white gauge measures drywall moisture content.

You can see that the needle has jumped to 100%, so the wall is wet as well.

This photo shows the shower in question.  The wall and floor measured above are just outside this location.

The homeowner had removed the drain cover so I could see it.

But if the drain is leaking, why would the wall be so wet?

That didn't follow.

I was very suspicious of the shelf though.

And looking at it carefully the edges had all been grouted and the grout was full of cracking.

It was cracking everywhere.

These folks have only lived in this new house for five months.  They did not have a pre-drywall inspection or a final as the builder convinced them that with so many inspections they would be wasting their money.

The shelf is definitely suspect.

So, how do we determine if my suspicions are correct?

We break out Mighty Mo!

So I had my client run the hot water for only about 2 minutes.  She directed the hand-held shower head right at the wall above the shelf and the shelf itself.

With the thermal camera looking at the spot on the wall where the moisture meter began to register such high moisture content, we can clearly see the shelf on the wall.

And we can clearly see where water is seeping through the cracking and making its way down the wall.  From there it gets out and under the bedroom flooring just outside the shower wall.

Easy peasy.

My recommendation:  thermal cameras can reveal things otherwise undetected.  In this case we knew there was moisture getting onto the wall and flooring.  But we could not see exactly why.  A thermal image makes it abundantly clear.  That's just 2 minutes of moisture driven onto the wall.  Imagine what happens during a shower!  So, when is a drain leak not a drain leak?  Well, when it's a wall leak.