I may have put a screw into a PVC drain pipe

[jwarren90]

Hi, I'm looking for advice on something stupid I may have done.

I bought a condo at the beginning of the year, and I spent a few months doing work on it. Some of it was done by professionals (new sinks, faucets, countertops, backsplash in the kitchen and bathroom) and some of it I did myself. I mostly did minor stuff like painting, changing outlets and switches, etc. on my own - nothing crazy.

One of the things that the home inspector pointed out was that the cabinets had been hung with drywall screws instead of cabinet screws. To avoid issues down the line, they suggested I back out the drywall screws and replace them with cabinet screws one at a time. I did this, but on one of the cabinets, I added two extra cabinet screws. I used a stud finder to find the stud, added the two extra screws, and went about with the rest of my projects.

I've been moved in for about two or three months now. It all of a dawned on me yesterday that the cabinet I added the extra screws to was directly in front of a PVC drain pipe that runs vertically up to the unit above me. In the under the counter cabinet below the one I added the extra screws to, you can see where my kitchen sink drain pipe connects to the one that goes up into the unit above and down to the unit below. I'm very concerned that I may have put one or two cabinet screws into the PVC drain pipe. I'm not 100% sure that I did, but I'm concerned because it's a possibility. I would have done this in the middle of February, so I don't specifically remember anything different about putting in those two extra screws. I imagine it would have felt/sounded different than all the other ones - but it's been so long now that I don't really remember.

I would need to remove the cabinet and cut a hole in the wall to see if I did in fact hit the pipe. I talked to a few friends about it (they are fairly handy, but by no means experts), and they say that even if I did hit the pipe, it is unlikely to cause any problems as the screw is in there, the water is only coming down from the unit above's kitchen sink, and the pipe is not under any pressure. I am worried about water slowly leaking into my wall and not realizing until it is a much bigger problem than taking down a cabinet, cutting a hole, and fixing a pipe. I wouldn't feel comfortable doing this sort of job, so I would need to hire someone to take care of it for me.

Any suggestions or advice? Please be gentle - I know this was an easily preventable mistake (and honestly the cabinet screws were probably unnecessary anyway).

 

[Sylvan]

1- If the cabinets were installed by a licensed contractor and you replaced the screws they are no longer responsible for any liability such as cabinets falling off the walls or puncturing a waste or vent or water line or causing electrical problems

2- If you did put a screw into a waste line eventually it will case a stoppage and it the screws are not stainless steel or brass they will rust out leaving a hole and possible minor leak

3- Even sheet rock screws when they penetrate a copper heating line may take years to show a leak

Good luck

 

[Sponsor]

 

[Mliu]

Were the two extra screws you added in-line with the other existing cabinet screws and the pipe? I'm curious if the problem is limited to your new screws or if the other screws may have also penetrated the pipe.

Before you start pulling down the cabinets and opening up the drywall, you might want to investigate further. I would start by removing the two screws that concern you and inserting an insulated solid 12ga wire into the hole (insulated for safety in case it contacts a concealed exposed live electrical wire, so don't be touching any exposed copper on your probing wire). Does the probe wire stop at the depth of the screw or does it continue into a hollow space? If it enters a hollow space and you leave the probe wire in overnight, does it come out wet?

 

[DIYorBust]

It may be hard to figure out if you're in a pipe, but maybe not that hard to figure out if you're in a stud. You have a stud finder, identify known studs and determine the distance between them. Is your screw in the right place for a stud, or is it between studs?

Another idea, Back out the screw and stick in a drill bit. What's coming out? Wood, you're good, PVC, you're going in.

Third idea, remove the screw and insert the nozzle of a can of great stuff expanding foam. Spray a generous amount, wait a few days and see what happens.

 

[Cacher_Chick]

We cannot see what you see. If it is centered off your sink, I would expect it to be the vent for your sink, to continuing to rise up in line with the drain.

 

[Reach4]

Steel cabinets? If not, I might check the resistance of the suspect screw to a metal pipe ground. If less than 1k ohms, I would think I screwed into a metal stud, or that I connected to steel mesh in a plaster wall.

If > 20 megohm, I would tend to think I am not into a PVC pipe with moisture inside.

In between, because that is a big gap, I don't know. Even if the cabinets are steel, it might be interesting to check.

 

[Mliu]

Another idea, Back out the screw and stick in a drill bit. What's coming out? Wood, you're good, PVC, you're going in.

Third idea, remove the screw and insert the nozzle of a can of great stuff expanding foam. Spray a generous amount, wait a few days and see what happens.

A bad idea followed by a much worse idea.

If you are in the surface of the pipe but haven't penetrated it, the drill bit surely will.

If you have penetrated the pipe and you fill that pipe full of expanding foam, expect hundreds (if not thousands) of dollars in repair and potential liability costs after you've put a permanent solid obstruction in your and your upstairs neighbor's DWV pipe. If it's a drain pipe, then the clog could cause overflowing fixtures upstairs (how much will it cost you to remediate water damage?). If it's a vent line, it could cause siphoned traps and the introduction of toxic gases into living quarters.

 

[Mliu]

If > 20 megohm, I would tend to think I am not into a PVC pipe with moisture inside.

I doubt that even an expensive Megger test will give you a conclusive determination. I know that a simple resistance test with a common ohmmeter will not.

 

[DIYorBust]

A bad idea followed by a much worse idea.

If you are in the surface of the pipe but haven't penetrated it, the drill bit surely will.

If you have penetrated the pipe and you fill that pipe full of expanding foam, expect hundreds (if not thousands) of dollars in repair and potential liability costs after you've put a permanent solid obstruction in your and your upstairs neighbor's DWV pipe. If it's a drain pipe, then the clog could cause overflowing fixtures upstairs (how much will it cost you to remediate water damage?). If it's a vent line, it could cause siphoned traps and the introduction of toxic gases into living quarters.

If he was able to anchor the cabinet to the pipe, it's probably not just on the surface, and the damage is already done.

The foam was a joke, sorry I guess you never know what people might do.

 

[Mliu]

If he was able to anchor the cabinet to the pipe, it's probably not just on the surface, and the damage is already done.

The cabinet was already hung on the wall. OP decided to add two extra screws and is now questioning their placement. Even if they hit the pipe, they may not have penetrated the inside wall of the pipe.

 

[Kreemoweet]

They have cameras on the end of long, snakey, flexible tubes. They're cheap, too, and even cheaper to rent. You can probably shove one up into the wall from the lower cabinet
area to see what's going on with the pipe, which is most likely nuthin'.

 

[DIYorBust]

They have cameras on the end of long, snakey, flexible tubes. They're cheap, too, and even cheaper to rent. You can probably shove one up into the wall from the lower cabinet
area to see what's going on with the pipe, which is most likely nuthin'.

What about the irony if he hits the pipe making an entry for the camera?

 

[Mliu]

They have cameras on the end of long, snakey, flexible tubes. They're cheap, too, and even cheaper to rent. You can probably shove one up into the wall from the lower cabinet
area to see what's going on with the pipe, which is most likely nuthin'.

Better yet, have a plumber scope the inside of the pipe.