Hello again, it's me, the guy that put his lawnmower blade on upside down, back with a new question...

So our shower drips, and I haven't found a way to stop it, but it's not much, and it's in the shower, and we can't get back in there to the valves or anything without removing part of the shower, so whatever, it drips, it's okay for now. We just bought the house in march and we have other things we're still working on.

So this week I'm replacing one of the bathroom faucets so I try to turn the water off underneath, and when I turn the valve it starts leaking from the valve itself. Okay, so I need to replace the valve soon, but to get this faucet project done real quick I can just turn the water off at the curb.

So I do that, and then turn on the other faucet to get all the water out of the system. Aaaaaaand it doesn't stop dripping. So I just go ahead and turn the valve back on because the water is off, and it starts dripping from the end of the connector.

Due to a different problem (I think the last person glued the sink flange to the drain pipe) I ended up not being able to replace the faucet, so I just reconnected it to the faucet to stop the dripping, which worked, but then the shower started dripping again. (The shower had stopped dripping during all of this other dripping.)

So, theories? My current leading theory is that maybe the water coming to our master bath is somehow coming through the attic so that maybe even when I turn the water off there's some left in the lines and both the valve under the sink and one of the shower valves is broken.

Shower stopped dripping because there was no pressure on the lines.
Sounds like the valve at the street needs replacing. Call the city.
What are your pipes? Galvanized, copper, PVC?
Repair the shower dripping from the valve. Call manufacturer for parts. Usually a lifetime warranty.

The shower dripping means you need to change the cartridge in the handle. Mine are Moen and use the 1222 cartridge. Here's a video on how to do it:

Change the shower cartridge.

When you go to replace the sink valve, turn the water off at the curb, bleed the line from the sink, put a bucket or container under the valve, and just replace it. It sounds like you just have a really bad valve and it's leaking because the line isn't completely bled (water could be trapped between valve and faucet or before valve). It doesn't sound like your main shut off is bad because there's no pressure in the line (It's dripping with faucet open, not running).

If this is an upstairs faucet, try bleeding the lines from your faucets downstairs. Everything higher than them should drain out.

I considered the street valve, but literally nothing else drips when the street valve is off, just this one bathroom valve/faucet.

I'll change the shower cartridge though, thanks for the video on that.