REPLACING an apparently cracked vent pipe in a wall of the small restroom of the school building (the one on the north side of the corridor between the classrooms, across from the chapel — called the Shemesh Restroom by the pre-school) is one of two non-emergency plumbing projects now being considered. (The other is to add a toilet in the space where the urinal used to be.)
 |
| Sample cracked vent pipe — is this what’s inside our wall? |
This post describes the situation.…
Over the summer, the odor of sewer gas suddenly became noticeable in this restroom. How harmful it is depends upon the concentration, but anyway it’s quite unpleasant for those who smell it.
Ellie arranged for a smoke test to be done by a plumbing company that’s known for such detective work. The plumber found that when he introduced a source of smoke into a clean-out pipe opening that’s located in the corridor, the smoke emerged inside the restroom. It appeared to come from behind the bookcase where the urinal had been. Presumably the sewer gas was getting into the restroom through openings in the wall.
 |
| Behind the bookcase (just after removal of the urinal) |
Ruben has since applied rope caulk (clay) around the three pipes that penetrate that wall, to seal the openings. Reportedly the stench has been greatly reduced. However, it is still noticeable to some (not to me — but my nose is not very sensitive).
According to the tester, the smoke result was evidence of either a cracked vent pipe or a cracked sewer drain pipe. Since nobody who was present at the time knew how to access the crawl space under the building, he was unable to check the sewer drain for leaks. However, I later checked myself and found no evidence of leaking sewage. So that leaves a cracked vent pipe as the purported culprit. Apparently such pipes can rupture with age, and then the gases that should be venting above the roof are instead lingering inside the wall. The fix is to open up the wall and replace the broken section of pipe. Of course, until the wall is opened, nobody knows exactly where or how long the crack is, and thus how easy it will be to replace.
The vent pipe inside the wall runs (presumably straight) up to the roof from the drain pipe that is downstream from the toilet. The photos below, taken in the crawl space, show the vent pipe’s location relative to the toilet drain, and to the urinal drain.
 |
| Relationship of vent to toilet drain (As usual, click/tap on an image to enlarge it.) |
 |
| Relationship of vent to urinal drain |
The restroom side of the wall is covered with tile, making it a messy way to access the vent pipe. Therefore it seems best to access it from other side of the wall, which is part of a classroom used daily by the pre-school. On that side, a large bulletin board covers much of that portion of the wall. (The door on the right is for a supply closet.)
Based on the 2003 HSR architectural drawing, the vent pipe should be exactly 5 feet to the left of the closet doorpost (see arrow, below).
[Updated 11/7:] Happily, since this post was first published, our final asbestos test results have shown that the level of asbestos in this wall is legally negligible. Workers and building occupants will not be placed at risk; no special precautions are needed.
Meanwhile, the EPA requires that any disturbance of the wall’s original paint layer(s) must be undertaken by a Lead-Safe Certified firm that follows lead-safe work practices if the affected area (hole cut in the wall) is 6 square feet or more.
It seems to me that the plumber will need to specify in advance where exactly the abatement contractor should open the wall, taking care to ensure that the opening is no more than 6 square feet. (For example, it could be 10" wide by 7 feet high, if that's workable.) Perhaps the top and bottom of the opening can be marked with blue painter's tape.
If it turns out that the section that needs to be replaced will extend all the way up to the roof, then perhaps the new piece can be lowered from the roof, thus avoiding the need to open up the entire height of the wall.
No comments:
Post a Comment