Showerpan leak inviting termite infestation?
We recently began an attempt at drywalling, starting in our master closet. With the paneling down, it was apparent that we have termites in the plywood behind the shower, probably due to some persistent moisture.
There is a a sheet of clear plastic (vapor barrier?) between the plywood wall of the shower and the studs. My concern here is that I don't see an obvious leak source through the plastic. When we run the shower, there is one spot where a nail appears to be leaching a small amount of water through to the closet side of the plywood, but additional condensation seems like this nail isn't the only source of moisture. The condensation appears as the shower gets hot, and the longer the shower, the more condensation. The condensation begins at the floor, and "grows" upward, and not only in the area of the suspect nail.
I have a series of questions here:
1) Is this condensation on the vapor barrier normal?
2) Is the shower pan failing? Any thoughts or experience with leaking pans?
3) Will simply re-grouting the shower fix the moisture problem (and for how long)? There are some cracked tiles in the shower, and the grout is looking a little crumbly in areas.
4) Do we need to start over with the whole shower? This would entail replacing the showerpan, walls and shower tile. Is this a project we can handle on our own? The shower pan in particular seems a little intimidating, but I think we could do the tile ourselves.
We've posted some pictures of the situation at http://bendystraw.com/termite/index.html
Thanks for any advice you might have! I'd really like to avoid a revisit of these termites for as long as possible.
One of the problems associated with the original Eichler shower pan is that the shower pan had no water tight membrane to prevent moisture from leaching into the ground. The original construction is basically: cut out the slab, pour concrete into the area that you step down from the slab, and cover with 1" tile and grout. while concrete takes care of sealing most of the moisture, it is like a sponge in that water will wick up, or leach down.
We recently uncovered a shower drain that had a hole at the bottom of the trap, and the soils below the pan we had removed were very damp.
I have seen a number of original Eichler showers that had subterrainean termites that were coming up through cracks in the slab in the walls adjacent to the shower.
Original Eichler shower pans are not up to current codes because they allow gray water into the groundwater. Your shower pan did not fail; it never succeeded to do its' job.
Another fun issue is that most of the original shower drains in
eichlers are 1-1/2", which does not comply with curent plumbing codes (current codes require that a shower drain needs to be 2" min.).
To correct this, the entire pan needs to be removed, the soils excavated around the drain to the connection to the vent pipe, a larger pipe is re-connected to the vent/drain, the drain extended up to be level with the slab. You can put in a precast cultured product pan to save a few $$ for a nice looking finish. Or build a curb then: have it pitched hot mopped, sealed with a pvc shower pan product, or have a copper pan made, and a good tile setter can take it from there. All building depts. require a shower pan inspection, and who ever installs the membrane can set up the test for the inspector.
If you want to preserve the step down shower pan, this can be accomplished by removing the pan, remving the damp soil and replacing with base rock or sand, installing a vapor barrier, a layer of sand, installing the drain, wrapping the plumbing in foam wrap and pouring re-inforced concrete (this should be sloped 1/4" per foot minimum towards the drain). Then the membrane can be installed, tile mud (4 parts sand, 1 part cement, 1 part lime) can be floated on the pan, and tile can be installed.
Or call a good tile setter, and he/she generally can take care of this whole project.
When I run these types of jobs, I enlist help from:
A. A hot mop specialist
B. A good tile setter
C. A plumber
D. One or many of my unsuspecting employees that are proficient with one of my jackhammers, shovels, and concrete trowels.
If you do the demo yourself, you will save quite a few $$, but hire people that specialize in the first three trades to avoid problems.
The only good news is that this will offer you the opprtunity to improve the enivonment by eliminating grey water in to the water table, the opportunity to improve/update your bathroom, the opportunity to arrest the termite problems, and the opportunity to take up home improvement as an avocation.
I'm sorry that I don't have any other concilatory remarks to offer you, it's late and my creativity is waning. Good luck, none the less, and I usually find the time to reply to emails from Eichler homeowners with home improvement questions, so feel free to write me if you need more advise.
