Disposal outlet/waste line height differential question

[indianajonesy]

So I'm 90% done (probably a hopeful exaggeration...) with renovating my kitchen and the wife decides to tell me she'd like a disposal. We conveniently have an abandoned wall box with power there (probably from a prior disposal), so I tell her sure.

Now I'm getting ready to order a disposal and plan my plumbing and I realize that my waste outlet is 7" from bottom of sink to centerline of the waste pipe. I see that ISE has a compact model which has a 6" centerline of outlet height. I have a fair amount of room to run piping as the old sink was a double basin end outlet and we now have a large (and deep...oops) center outlet single bowl, so my question really is if this 1" differential is enough to prevent standing water in the disposal?

Moving the waste line lower is theoretically possible, but would require removal of the counter and several cabinets that I just finished installing, so not a great option.

 

[Dj2]

Can you upload a pic?

Wives often do it, they make last minute 'change of mind'.
Cities often do it, they re-pave a street, then open it up to replace a rusty pipe.

 

[Sponsor]

 

[indianajonesy]

Can you upload a pic?

You can see a bit in this one (before I hung the sink):

And a bit more in this one:

I'll be over there later today and I'll grab a better one.

 

[Terry]

If the drain is 1" lower than the outlet on the disposer you won't have standing water. A standard p-trap may not work, and it might need a reversing p-trap there.

 

[Reach4]

You might be replacing that 90 with a 45.

 

[indianajonesy]

You might be replacing that 90 with a 45.

Yeah, that was my thought as well. That J-bend is a Keeney reversible one, so should be minimal modifications otherwise...just a 45 and a disposal elbow into the trap. I'll pick up the disposal and give it a try.