Has anyone encountered a channel drain (also sometimes referred to as trench or line drain) here in the US? See the web link below for an idea of what I'm referring to. I'm trying to find a source for this type of product for my bathroom remodel (guest and master baths). It seems as though they're more common in Europe and Australia. Would appreciate any leads! Here is a link that might be useful: Channel Drain Example

Plumbing new drains and vents can be complicated, but in this case it seems you are just replacing your old shower pan and drain with a new curbless design. You are not really changing the basic plumbing design; you are just trying to get the drain to align. I assume you have fully researched the design for a curbless shower, since that is more complicated to implement than your plumbing changes. In most cases its easier to use a pre-sloped pan covered with a waterproof membrane by Schluter or other good company. They recommend also using waterproofing membrane under the bathroom floor for several feet around the shower, since its hard to predict how much water will end up on the floor when you have a curbless design. This company has a low profile P-trap, but I'm not sure it will be low enough for what you need. https://pvcpipesupplies.com/1-1-2-p-trap-low-profile-dwv-fitting-d706-016.html If the vertical pipe in the wall is accessible and made out of PVC or ABS, it is a relatively simple job to cut it and lower the drain connection. If you are motivated enough to break up concrete, cutting into and splicing a drain pipe should not be that hard for you. Bruce

Cat_ky, I will probably do that eventually. I don't know how they'll look into this other than cutting into the ceiling below--unless they can see what they need to see by removing that gasket. I just did some measuring, and it actually looks like my shower straddles my laundry room and garage. The drain is probably right above a wall. I might try asking my neighbors via Nextdoor if their drains appear the same. The part that really concerns me is the top of the pipe and how it's raised above the gasket and the edges are rough--doesn't look like the water will all drain out properly and will instead sit on top of the o'ring.

My drain cover has no screws in the master bath because I didnt wajt to have to unscrew it if I wanted to clean out the drain. I got mine from Designer Drains and they have versions with screws or without. It stays on quite well. I used to have a hair catcher that wejt over my previous drain cover and it worked well.