Ceramic tile and grout

I use color-matched latex caulk for most movement related caulking, such as in wall corners. In showers and wet areas I use the closest match of silicone or polyurethane caulk.

You do that if you want to have a real workout when you try to remove the caulk to replace it several years down the road. We just had to do this. Nothing like caulk reinforced with grout!

JK

Use caulk whenever the substrate changes direction (changes plane, not direction on the same plane) or material changes. So corners, at fixtures like bathtub or toilet, where a tile backsplash meets tile countertop, where baseboard cove tile meets floor, where floor tile meet door threshold, etc. These areas are able and likely to move relative to each other, so you want the flexibility of caulk.

Do all the grout first, then tape off the areas to be talked, caulk and smooth, and remove the tape before the caulk sets.

As another poster said, use color matched silicon or urethane, and get the kind with a mildewcide (usually labeled for kitchen or bath use).

HTH,

Paul