My house has a 30-year old bump-out on the north side that included a bathroom, an adjacent bedroom, another bathroom and another bedroom adjacent to that. The whole house is on concrete slab, as are most post-1960 houses in Southern California.
The first bath has a jaccuzzi tub, for which the contractor left an opening through the slab to make room for the trap and waste line, so there is a 3-foot long trench with perhaps 2 square feet of bare dirt. There is an access opening in the wall between the tub and the adjacent bedroom with just a 3/4″ plywood door covering it.
The problem: A strong musty smell in the adjacent bedroom has been getting steadily worse for several years. Humidity in there has also been very high even before the odor appeared. I have pulled some of the drywall off to check for mold, but there is no sign of mold or mildew on the paper. I suspect the bare earth under the jaccuzzi as the source of odor, but it seems odd that there is no such odor in the second bathroom that has a frickken garden with large area of bare earth.
That second bathroom has a partly sunken tile tub and an atrium with 24 sq feet of bare dirt and some plants. There is no musty odor in the bathroom. The adjacent bedroom has an access door for the sunken tub. That access space is all concrete, no bare dirt. It smells a little musty inside, but none of that odor is noticeable in the adjacent bedroom.
Any suggestions for fixing the problem on the first bedroom?
I thought of digging the trench under the tub a little deeper and pouring concrete in the trench, but access is difficult for digging.
Is there a liquid material I could pour into the trench that would seal the dirt without having to try to dig where access is difficult at best?
Replies
I suspect there's a leak somewhere that you haven't found yet.
I had the same problem at my house. Both bathrooms had a 12"x12" hole where the drain from the tub was installed, same musty smell. Check for leaks first, then just close up the hole with concrete, making sure you add gravel if needed. I like the fiber reinforced concrete, and I treated the existing slab with an acrylic bonder. The last step was a skim coat when the concrete had cured long enough and I caulked aroung the drain pipe.
I'm sure that the plumbers around here will disagree, seeing as how that hole is easy access should you need to replace or repair the shower drain. The way that I see it is, if I have a plumbing problem, then chances are that slab is coming up anyways.
You might have to get a little creative to pour in such a confined place. I ended up building a chute out of 1x4s and just poured what I needed onto the chute and into the hole.
Thanks for the confirmation and pouring suggestion. I was trying to figure out how to get concrete through a narrow opening 3 feet back under a tub. Constructing a chute and a push rod would be just the trick.By fiber reinforced concrete, do you mean the quick-setting stuff used for stucco patches and such?BruceT
Edited 11/14/2008 2:29 am by brucet9