I would agree with Isaac. The tile floor is sitting higher than the ORIGINAL hardwood. Traditionally homes are BUILT with different floors being level with each other. A tile floor will sit 3/4" high once finished. That means you have MORE THAN one floor there.

Be prepared for the demolition to take on a twist. It will cost more to remove both layers. Once the tile (and original) floor is gone you can then find out what can be done and with what material.

When was the house built?

Thank you both for the input! The house is from 1921 and I have a feeling you're right about the tile being laid on top of an original floor. Should be an interesting demo!

(agree with all the above, but also, if it turns out that the floors wil end up at different levels, it's still ok. use a sloped transition like you have currently, and it will work ok.)

1921 is right in the heart of the "lead and asbestos" eras. Before demolition begins you may have to test some of the layers (if there is a visual indication that something might be wrong) for asbestos or lead (lead is more likely if the floors were painted).

Before you go hog wild thinking you can get your wood floors refinished...please measure the wood. You can do this by finding a cross section of the floor (floor vents are SUPER helpful with this). You want to measure the amount of wood that sits ABOVE the tongue. You need 3mm of wood to have a successful sand and refinish.

If the wood floors are original to the house (and I have every belief they are) then they may not have much life left in them. Wood floors can have a life span of 60-80 years. The occasional hardwood (something sitting under carpet x40 years) will go 100 years.

A house built in 1921 = 101 years old. The original wood floors may be on their last 'life' span. It is possible they do not have another sand/refinish in them. Please check before you go on with anything (asbestos and lead testing can occur while you make your decisions).

1921 means you should definitely be on the lookout for asbestos tile and mastic. The mastic in particular is supposed to be tricky to remove safely, unfortunately.

Hopefully you just find wood and/or non-asbestos linoleum!

If you have wood floors in the kitchen, they may be hardwood or softwood. In either case, if you are lucky, the builders may have put linoleum over the wood from the very beginning. For some reason this was done in some cases, or so I have read. Alternately, if there is wood, it probably hasn't experienced 100 years of wear - at the very least it was covered by tile for part of that time. And hardwood can last more than 100 years - our 1915 floors are still going strong.

My parents removed asbestos floors in the kitchen of their 1920s home in the 70s, and found a softwood subfloor that was in really good shape. They finished it and used that subfloor as their final flooring, and it has held up (a bit dinged, admittedly) for 45 years. They do have a small transition to the kitchen floor, down instead of up, since it is a subfloor. May you be as lucky as they were!