What's best to stick granite backsplash to granite countertop?

Question

Forgive my lack of knowledge here.

New bathroom vanity.
Black granite countertop and 3" tall backsplash.
Countertop, and will-be-visible faces of backsplash, are polished and factory sealed.

** Backsplash will be about 2" from wall **

What specific product is best to use to "glue" the backsplash to the countertop?
(googling seems to suggest some sort of epoxy, but wondering if that might be too brittle, or discolour...?)

Do I need to sand the polished & sealed countertop where the backsplash will sit?

Do I need to caulk when the "glue" is set, and with any specific caulk?

Here's the relevant bit of the "installation guide". There is no text...

Thanks in advance...

**** EDIT **** For clarification, the backsplash won't be against a wall but it will be near it. About 2 inches away. And we have little kids so I'd like to use the backsplash to stop stuff running down the back of the cabinet where it will be hard to clean.

Answer 1

Clear, slow (ie, not 5 minute set time) epoxy is what I'd use. Apply masking tape on the countertop exactly at the seam line. Same for the backsplash. Glue and set the backsplash (clamp gently in place), and wipe the joint clean of the excess. (Disposable gloves will be your friend, here, as epoxy is hard to clean.) Pull the tape and wipe the joint one more time. Have whatever recommended solvent on hand for cleanup in case you get any epoxy where it shouldn't be.

My gut feeling is that this sort of setup is usually used against a wall, so they aren't expecting the backsplash to take a lot of abuse. Since you aren't against a wall, be careful in the future.

I don't think there's a need to rough up the mating surfaces, but it can't hurt.

And since you have a perfectly waterproof joint, I wouldn't bother with caulk.

Answer 2

YOU DON'T.

If it isn't against a wall then it serves no function. The point of the backsplash is so the wall isn't hit with water. You want water on the sink (in a normal vanity situation) to go to the floor.

Since in your situation water will go straight to floor, this piece is completely non-functional. Not only is it non-functional, but please ask the manufacturer if they recommend it being installed - not against a wall.

Also...

• The back of it will be unfinished and look bad.
• Even from the front it will not look good and be weird sitting up there like that.
• If you glue/epoxy it you make break the granite below if it is bumped, hit or whatever
• If you glue/epoxy it and it is bumped, it could be dangerous

Instead add molding

An alternative and there are several different types of trim based on the look you want is to install a matching granite trim piece. An example below is granite pencil molding. You could simply apply clear silicone to install this. It will look better, function better, not be a hazard and if it ever does come off it won't take the other granite with it.