The traditional way to deal with higher bathroom flooring is with a marble saddle at the bathroom door with one side beveled to be lower than the other. The door would probably have to be undercut a bit more.

mtsoni = spammer? Thanks but no thanks, not clicking on your link.

Thank you, handymac and Renovator8, for posting.

We're using through body porcelain tile so we can bullnose or bevel the edge of the tile at the threshold.

handymac, I'd appreciate it if you'd clarify your statements a bit more. Why do you think that "Using even a custom transition strip when the hard surface is higher than the carpet usually does not work well"? Do you mean that it becomes a trip hazard? Or is there another reason?

By "So, you might wind up adding 3/4" to the carpeted areas just to get the heated floors in the baths" are you suggesting that we add underlayment before we re-carpet? If so, how do we address the differences at the stairs? Do we gradually raise the height of the top steps? I'd think we'd need to do something or else the top step will be 3/4" higher than all the others and that would be noticeable.

Thanks!

A marble saddle is designed to take the stress of foot traffic but a tile bullnose is not.

But we're not using marble. I really don't want my only other choice to be a metal strip.

What is it about a marble saddle that makes it handle foot traffic? The thickness, the edging profile or ?

Thanks!

Marble is much harder than ceramic tile and it doesn't have joints. It's the traditional material for this condition and comes in all colors. Why wouldn't you use it?

A marble saddle at a bathroom door is not only a way to transition between different flooring heights; it is traditionally higher than either floor surface so it helps to fill the door undercut and reduces the sound transfer between the rooms. The purpose of the door undercut is to allow the bottom of the door to clear any mats or rugs that it might swing over.

Even if you don't use area rugs or mats a saddle allows a smaller space under the door when closed.

Marble is harder than porcelain tile? I've banged pans on my porcelain tile island and it's never chipped. Can't imagine a marble counter faring as well but the only marble we have is the inset piece of Carrara on each of the antique nightstands in the MBR (and each has at least one chip acquired before we purchased the pair).

Thanks for explaining the reason for a marble saddle. As for why we aren't using one, it's because no one has mentioned that option to us (interviewed 5 contractors and have talked to 4 flooring contractors). Maybe it's not common in my area. I don't think I've ever seen a bathroom with a marble saddle, including bathrooms with marble floors (and I go on all the new and remodeled home tours in the area). I'll have to ask about it.

I know marble comes in many colors - I fell in love with slabs of Emperador and Crema Marfil at the local stone yard - but I'm not sure how it will look with our tile choice. And I'm definitely not starting over! LOL

I've got tile-to-carpet transitions all over my house (5 places) and have no trouble with height differences. Even in our master bath, which has heated floors. Our recipe:
Subfloor
Wire taped to subfloor
Ditra thinsetted over top of wire
Porcelain tile thinsetted over Ditra

We put metal edging strips where tile meets carpet. They're only about 1/4" wide, and we chose off white painted metal ones, to coordinate best with our tile. But the carpet covers it up, so it's really not noticeable.

" handymac, I'd appreciate it if you'd clarify your statements a bit more. Why do you think that "Using even a custom transition strip when the hard surface is higher than the carpet usually does not work well"? Do you mean that it becomes a trip hazard? Or is there another reason?

Transition strips have to be stable---both sides have to have support. In the example above, the strip is supported by the hard surface, but will nor be supported by the carpet/pad sufficiently unless the strip compresses the carpet/pad quite a lot. That usually results in a squashed carpet look most folks do not like.

By "So, you might wind up adding 3/4" to the carpeted areas just to get the heated floors in the baths" are you suggesting that we add underlayment before we re-carpet? If so, how do we address the differences at the stairs? Do we gradually raise the height of the top steps? I'd think we'd need to do something or else the top step will be 3/4" higher than all the others and that would be noticeable."

Adding 3/4" under the carpet is what I meant.

As for the stairs, I have seen a landing area(at the original floor height) done at the top of the stairs, maybe 4' by 3' and a transition strip used between the carpet and the landing area. Maybe solid surface flooring or vinyl tile. That minimizes the height difference at the top step and a 3/4" visual difference does not create a trip hazard.

Thanks for the pic, weedyacres. When I returned all the tile samples to the supplier yesterday, she showed me metal strips that they use to protect the tile's edge that is very similar to what you did. So we have that choice, too.

Thanks, handymac, for explaining what you meant. I should have clarified that the tile - and whatever transition we might end up using - will be supported by a hard surface. The carpet outside the bathroom was destroyed during the toilet flood so it's gone (pad, too). Since it won't be replaced until the bathroom remodels are completed (we're remodeling the MBTH next), we can lay carpet and pad as necessary and appropriate. (I would not be happy with compressed pad and carpet either.)

After talking to a friend who's a CMKBD in the bay area, I think we are going to install underlayment (1/2", 5/8" or 3/4", not sure what's standard in our area at present) before we have the new carpet installed. The hallway is carpeted to the stairs and the stairs are carpeted so we can't do a transition landing at the stairs as you suggest. Instead, we'll need to add gradually thinner boards or felt board or whatever the stuff is called, sized to cover the entire width and length of each stair, to several steps at the top to make the new floor height less noticeable. It's all doable. In fact, this is likely something hubby and I can do.

Thanks, everyone, for your help!

Placing something underneath is always safe as it keeps the expensive rug safe and intact.