valve cover plate size options

Hi everyone - I've given up trying to fix my 1920's shower valves that wont stop leaking through the stem. With a baby on the way I want to replace the valves and call it a day with a fancy new thermostatic valve.

I'd like to do this with a remodel plate as I cannot go in from the back, and wifey really doesnt want me knocking down the existing tile wall. I'm somewhat confident in my ability to replace the setup from inside the hole create by the cover plate ( I know the supply lines to the bathroom are galvanized, but I am pretty sure the feed lines are brass...otherwise its a whole new ballgame if I have to either use PEX or create dielectric connections (can you even do that inside a wall?).


What I am running into is that the width between the outer edge of the existing valve cutouts is a hair over 13" and all of the cover plates I am finding are set at 13". Does anyone know if there are any larger sized ones available? Say 15"? that would give me piece of mind?

Plan B is to try and selectively remove the tiles from the middle of the wall, open it up, do my thing, then create some kind of backer and re-adhere the tiles directly...


Thanks

If it is galvanized, there is very little chance that the rest of the piping is brass OR copper. In addition, there is almost no way you can make a hole which can be covered by a remodel plate to replace the valve with screwed piping, PEX, or copper and dielectrics. You must have an 11" center to center valve to need an opening that wide. If so, I doubt that you will find a cover plate that wide, anyway.

hj said:

If it is galvanized, there is very little chance that the rest of the piping is brass OR copper. In addition, there is almost no way you can make a hole which can be covered by a remodel plate to replace the valve with screwed piping, PEX, or copper and dielectrics. You must have an 11" center to center valve to need an opening that wide. If so, I doubt that you will find a cover plate that wide, anyway.

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hmm....the supply pipes heading upstairs sure seem like they are galvanized, but the stuff in the wall sure seems like it is bronze.

I assumed that when I opened the coverplate hole I would be able to cut off the ?dropear? for the existing valve and solder on connections to bring it to a newer valve.

I found this picture I took a while ago of the supply lines heading upstairs (as I want to replace the 1/2pex with 3/4pex)

looking at this again, the pipes almost look like black pipe....

I've found remnants of corroded and abandoned pipes in the walls which lead me to think these were galvanized.

The problem will be that you cannot "unscrew" any of the galvanized pipe fittings unless there are unions right at the valve, and even if so, not enough room to make a transition.

Depending on the layout of the walls, it might be possible to fish pex up through the wall from the basement or crawl.

Not many houses out there that are impossible to access the wet wall from the backside.

I won't be able to fish anything up easily as the supply comes in on the opposite side of the tub.

I can get to the wet wall but I would have to completely dissemble a built in cabinet. I'd rather smash in the front than deal with that.

I assume that if there is brass pipe at the valves I could just cut it and solder a fitting on. Is that not a valid assumption?

If there is any brass pipe, it is sized at the equivilant iron pipe size, which is meant to be threaded. Any sweat fittings commonly used today are copper tubing size, which is not interchangeable.

cacher_chick said:

If there is any brass pipe, it is sized at the equivilant iron pipe size, which is meant to be threaded. Any sweat fittings commonly used today are copper tubing size, which is not interchangeable.

Click to expand...

Very interesting. So I may open this up, find out that the supplies going to the valves are brass, which leaves my only option to unthread them, which may be very difficult. If I cut them, there is not a logical way to connect them to something else without re-threading them?

Sounds like this a mess.

Is there no way to go from cut brass/ips size to a copper size?

I was perusing...I found this picture. Im pretty sure this is whats behind the wall. There is an access panel in the closet but it only reaches the the top of the tub, pretty much worthless except when suctioning the drain. This is what it looks like in there, although I cant see the top of the connections where the tub valves are. I also don't remember seeing any unions. This is much easier for me to access, so now that I know what to look for, I can take some pictures up into the wall and see whats hiding back there.

http://inspectapedia.com/plumbing/92_Hooker_Pok_745_DJFs.jpg