Help with new sink install

Hope the more knowledgeable here can give me some advice. I'm trying to select a sink and would like to avoid having to lower the existing drain. The sink will be an undermount. The drain (into the wall) is 16" on center from the floor of the sink base, and the counter will be at 29" from the floor of the sink base. So that's 13" from the bottom of the counter to the center of the drain. I'm looking at 10" deep sinks and thinking that 13" is just not enough space for 10" sink, disposal, s-trap and all. Am I right? I'm also looking at a sink that has one side 10" deep and the other 8" deep. If 10" is too much sink, would hooking the disposal to the 8" side work better? Or would I be better off just going with an 8" deep sink and not take chances? Or, is even an 8" deep sink too deep for that drain location? The old sink was a drop in and was (I think) 7" deep and there was very little vertical plumbing, just a T joining the sinks connecting to a common S-trap.

sink

It appears that this will be a kitchen sink. Who will be using it? Midgets? All conventional kitchen cabinets are 36" high and the drains in the wall are installed to connect to something that high. Lowering the sink top that much will make you do some "creative" plumbing to make the connections, but we cannot tell you how to do it. If we were there and doing it there might be two or three possibilities, depending on the actual situation.

Hmmm, not sure what I said that makes you think the counter is lower than normal. I said 29" from bottom of counter to floor of cabinet, not the kitchen floor.

Also, when I said S-Trap, I, of course, meant P-trap.

drain

Missed the "bottom of the cabinet" part since we measure to the floor. Which is why the problem should have been detected before the cabinets were installed, unless these are existing cabinets and you are just replacing the top. Your disposer will be the limiting factor since the drain can be split into two branches so that each sink has its own trap, which will reduce the height requirement immensely. Also if you have a dual height sink the disposer will usually go into the smaller shallower one, again helping with your height problem.

Thanks for replying. Yeah, didn't really think about it until the cabinets were already in. Luckily, the DW goes beside the sink base so it's not too difficult to pull the sink base back out of the way. If I had more experience I'd probably have noticed that the drain is higher than "normal" while doing the demolition. I'm not there right now, but looking at my GD here I'd say that with a 10" sink, the GD output would probably be about 3" or maybe even more below the drain into the wall...that doesn't seem good. Even with an 8" deep sink, I think I'm asking for trouble. It seems the safest way to go is to lower the drain, I just have to convince myself of that. It's an old farmhouse though and even though the plumbing has been redone 10 yrs or so ago, I just never know what I'm going to find when I start tearing stuff up.

drain

IF the disposer outlet is even 1/2" below the pipe in the wall it will have standing water in it. That will affect the longevity of the disposer and also cause vibrations when the diposer is turned on until the water can be "pumped' out into the drain.