General Plumbing Questions General Plumbing Questions

If you’ve got plumbing questions or need plumbing help, be sure that others have probably encountered the same issues. Take a look at the following Q&A’s, which address a variety of common plumbing problems.

Q. What should the water pressure be in my home?

A. 40 to 60 pounds is "normal." Over 80 is too high and will cause problems with your plumbing fixtures and water heater. You can buy an inexpensive test gauge that attaches to an outside faucet. Just be sure to run the water a bit before hooking it up so you do not get a false reading from air trapped in the gauge.

Q. I am doing a new bathroom my second floor. On the work permit the approver wrote "no dry vents below the waste." Could you please explain to me what it means?


A. It means you cannot connect the vents from the downstairs fixtures into the stack that goes up to the upstairs bath until you are well above the upstairs fixtures. Vents cannot merge until they are something like 6" inches above the flood level of the highest fixtures being vented. In other words, if you don't connect the waste pipe from the upstairs bath into the existing waste plumbing above any of the downstairs fixtures, you should be okay. Don't connect the vent pipes from the downstairs fixtures into the upstairs vents until you are up in the attic - or well above the upstairs fixtures. There is such a thing as wet venting, but you'd better look at a plumbing book at the library for that one, something with good pictures. What you don't want to be doing is flushing your upstairs toilet into the vent for the downstairs sink. You cannot have a vent tie back into a stack, at a level below or the same as, a branch that receives water from a toilet and when the toilet is above a laboratory or sink and on the same stack. You will have to reroute the existing vents to above the connection you make for the new bathroom. You may or may not have a problem. You just need to look around at your plumbing setup. The reason is that a slug of water from the toilet going past a dry vent connection could pull enough of a vacuum to siphon water from trap seals on the vented line.

Q. I am trying to get more water pressure out of my shower. I have installed several heads and have removed several water saving devices, but I think since we are on a well and this shower is on the top floor four floors, the water has to travel a long way to get to the shower head. The water is way too hot when it is on full. Is there any way I can maintain that pressure without the high pressure being on full heat?


A. You would have to change the valve to a pressure-balanced valve in order to eliminate the temperature variance.

Q. I was just wondering if there is a limitation to the type of shutoff valves that can be used underneath a kitchen sink.


A. There is no code requirement as to specific type of shutoff. The type most frequently used is the angle valve, and with good reason. They are simple to install and come in different configurations. I have also seen ball or gate valves used, as well as threaded, sweated, or compression. Go with whatever works for you.

Q. I have a gurgling sound coming from our kitchen sink and utility room sink. Recently a plumber put two vents in the toilet lines to vent the toilets. He told me that I only had one roof vent for the entire house. I have five sinks and three toilets in the house. Do I need to have vents installed in sink lines, such as were installed in the toilet lines?

A. What you describe certainly sounds like air being pulled through the laundry and kitchen sink traps. I assume you've run water to make sure those traps are full and sealed. If you do that and still have the gurgling, it sounds to me like the vents for those fixtures are not working or non-existent. I'm curious if you had this before the toilet vent was installed. On the other hand, if you didn't have a toilet vent, I wonder if you have any of the other vents you are supposed to have. I also wonder where water is running when you hear the gurgling. Is it all the time, or just when the toilet is flushed or the shower running? In any case, yes, every fixture needs to be vented one way or the other. You can join vents in the attic so you don't have to put another hole in the roof.

Q. My pipe leading to my outside water spigot has split open in my basement. Do I have to replace the pipe or can I get some type coupler to go over the split and seal it up?

A. If the frost-free type are 10" long or more and the washer that actually shuts the water off is on the end inside the house, you will have to replace the whole faucet assembly. If it is just a pipe, you will have to put in a new piece of pipe. Where the pipe split will be thinner metal and will probably leak no matter how you try to patch it.

Q. I recently discovered a floor drain in the basement that was covered with a carpet by the previous owners. It is getting really stinky and making the basement a no-go zone. I need some ideas on how to deal with this. I have tried flushing the drain out with a hosepipe but it still stinks. I am thinking of capping the drain off. What is the best method?

A. You might have a partially clogged drain that is allowing backup to come to that drain. A good cleaning with a hose usually does the trick. You can cap it off with a twist-in plug so that it is not permanent; you might need it if the basement ever floods.

Q. I am looking to build a bath in the basement of an older home. How does one map out where the drain lines are located before busting through the concrete? For iron pipe will a metal detector work? I would like to know in the planning phase before soliciting bids.

A. The best way is a pipe camera. This inspection will completely lay out the plumbing, along with finding any problems before starting.

Q. Whenever we run water in our kitchen sink, the drain makes a gurgling sound for about 30 seconds. Our plumber said this was "normal" but we'd like to make it go away. I've read I might need an air admittance valve. Will this fix the problem? Does it just install under the sink somewhere?

A. It depends on the plumbing codes in your area. Some do not allow Air Admittance Valves. That would be the way to go though.

Q. I have a leak in my shower diverter and I can't seem to remove the diverter in order to replace it. I think it's a Waltec. When I pull it out to divert the water to the showerhead, water continues to come out the spout as well as spray out of the diverter itself. Can you please give me some advice?

A. You can change the whole spout. Look under the spout where it meets the wall/tub. If there is a slot there, it has a set screw which when loosened or removed, will allow the spout to pull off the supply pipe. If there is no slot, it screws onto the supply pipe. Turn it counter-clockwise to remove. If it is the screw-on type, make sure the internal threads are the same distance from the back of the spout on the new one. Otherwise, you would have to lengthen or shorten the supply pipe. Re-caulk when done to prevent water from running behind the wall.

Q. I replaced my old bathtub with a new soaker tub. Simple plumbing, or so I thought. I replaced the copper piping and the PVC drain piping, put the tub in and installed the new faucet. I drew a bath in my new tub the other week and when I turn off the water, I hear a slight trickle. To my horror, I peek over the tub and see a slow but steady pool of water making its way from the bottom on the tub to the door. I don't know what it causing it! I am almost 100 percent sure it is not the copper piping going to the bathtub. I still don't have the tiling around the tub. I am thinking it is coming somewhere from the drain maybe? Is there putty or something you have to use with the drain to make it water proof?

A. Since you still have access to the drainpipes, it's an easy fix. Yes, there should be a sealant under the flange, either plumbers putty or silicone. Unscrew the flange, make sure everything there is dry, install the sealant, and then screw it back down. With plumber's putty, you can use it right away; with silicone, you must wait a day for it to set. If you decide to use silicone, use some masking tape around the outside of the flange. It makes cleaning up a lot easier.
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