I live in a single story, 45 year old, concrete slab foundation home on the Gulf Coast. My problem is that the shower drain P trap, located in/under the slab appears to be leaking. After showering, the level in the drain/P trap falls and the loop seal is lost. The P trap appears to be approximately 8 inches below the shower floor. This causes/allows 1) Roaches to crawl up through the drain from the septic line into the shower. Some nights 10 or more roaches will appear in the shower. My wife hates this. 2) Loud drain flow sounds emanating when a commode is flushed.

The shower continues to drain well. However these roaches are annoying. A wash cloth sprayed with roach spray placed over the drain keeps them at bay. I suspect a small amount of shower water is leaking out of the P trap into the soil below the slab. I think I may have caused the leak by using bleach mixture to clean mold from the shower wall for 20 years. I believe the metal drain/trap was attacked by the standing bleach after each cleaning. Surprisingly, we do not have bad odors emanating from the drain.

My questions are:

1) Is it possible to repair the P trap without tearing up the shower floor and concrete below? The shower is tile over concrete slab and tile over sheet rock on the walls.

2) Have you heard of anyone using a belzona type product applied with flexible brush to patch the metal drain/P trap? Is there a kit available?

3) Do you know of a kit whereby a flexible drain liner could be inserted into the drain pipe through the P trap and sealed at the shower floor for repair? I am trying to avoid the $ thousands it will take to replace the drain piping, shower pan, and tile.

4) If I continue to use the shower, do I risk additional damage to the house, such as foundation damage due to leaking water?

speedball1

Greetings from Sarasota,
Would you say that these "loud noises" are gurgles? I don't think it';s your "P" trap or your drain and I've never heard of bleach eating up a metal drain. Let's check and see.
Fill the trap with water and have someone shine a light down there when you flush a toilet. Did that affect the trap seal level?" Did the water in the trap move? Let me know, Tom

dcsicking

Response from dcsicking: No I would not say the noises are gurgles. It is more like loud rushing noises. It is a steady hi velocity flow noise that stops as all the water passes. Also, if I have just showered and the P trap is full, then flushing of the commode is not heard through the shower drain.

I have done this much already. I filled the P trap and measured level in the drain. I then waited several hours and measured the level in the drain line again. It had fallen by a couple of inches. That is why I suspect the P trap slowly drains allowing for falling level. Also with no level in P trap that allows easy access for roaches living in the septic line, I think.

Your suggestion to test seal water level while flushing a commode is good. However, I am at work now and cannot do this. I will try it when I get home tonight and will respond again.

This forum is great! I really appreciate you taking the time to help me, a complete stranger.

speedball1

When you log on to AMHD you're no longer a strainger.
You have a force of experts just waiting to help.
Let me know about the trap seal. Something's lowering the seal and I wanna know what. Regards. tom, Tom

dcsicking

Response from dcsicking: I did as you asked and observed the following.

1. Before flusing any toilets I measured the level again in the drain. The depth of the drain is 14 inches. Water was standing at 1.5 inches (in the 14 inch drain)prior to any flushing. No one showered since this morning.

2. I then flushed the toilet in the same bathroom. The level rippled a little. It appeared that air was rushing over the top of the water causing rippling, definitely was not bubbling through the water.

3. I then flushed (rather had my wife to) the toilet in the adjacent bathroom. I saw similar results as air seemd to rush over the surface causing a slight rippling effect.

4. Then I ran the shower for a bit to fill the trap. I then measured a level of 4 inches in the drain. ( up from 1.5 inches)

5. I then had my wife flush the toilet in the same bathroom. The surface did not riple this time. The water level rose and fell (breathed) ever so slightly. The level may have risen and fell for a few seconds of 1/8 to 1/4 inch. No bubbling this time either. This breathing effect was very slight.

6. I then repeated the process for the toilet in the adjacent bathroom and got similar results.

It appears to me that with low level in the trap air moves through the "P" trap above the water and whispers accros the surface creating a ripple effect.

With normal level in the trap, there is no air accross the surface, but the entire water level rises and falls a bit with slightly increased air pressure in the septic line due to rushing water below. I.E as the water runs down the septic line air will be rushing back up to fill the space left by the water causng a slight increase in air pressure and the breathing effect.

This is my understanding. I want to know what you think?

Dan Sicking

speedball1

Some fluctuations normal. The vent prevents suctioning of the trap seal.
Did the water drain down from the 4 inches back to 1 1/2"? 4 inches is way too high in the trap. The average trap seal runs between 1 and 2 inches. Something's not draining right. Something's preventing the shower from draining correctly. Answer my question about the trap seal. Does the 4" eventually drain out leaving a 1 1/2" seal?
Back to you, Tom

dcsicking

Response from dcsicking:

The level does drain down slowly. I do not know how long it takes to drain down the "P" trap. Yesterday my wife showered at approximately 6 AM. The level should have been 4" after her shower. By 8 PM last night the level fell to 1.5". After the refill process last night I checked the level twice, about 15 minutes apart. The level stayed at 4" over the 15 minute period. So it must take awhile for the level to drop from 4" to 1.5". I think I can safely say that it takes hours to drain the level back to 1.5" or lower.

By the way, I did not hear the rushing sound last night when flushing the commodes, not with level at either height. If we do not shower for a couple of days then the level must fall even further, possibly emptying the trap, because that is when the flushing noise becomes very loud.

Thanks for your help!

Dan

speedball1

That concerns me. It sounds like the trap's leaking from the bell of the "U" bend. This would mean taking up the shower floor and I'm not ready to suggest that.
Let's be very sure about this. Don't use the shower for a few days and monitor the trap level day by day. I want to see if the trap will go completely dry. Good luck and let me know, Tom

dcsicking

We have company this week. I cannot secure the shower until they leave. I will begin the process of securing shower and measuring P trap level next Tuesday.

Thanks!

Dan

speedball1

Let me know how you make out. Good luck, Tom