As a professional interior design, I always tell my clients that real hardwood flooring is typically not warranted to go into bathroom areas. However, many builder's install them into the powder room areas to save money. I always ask, "Are you prepared to clean up any "Miss the Bowl" accidents quickly?" Hardwood is very porous and liquids can seep into the wood causing discoloration and can hold onto terrible smells, if you know what I mean?

There are plenty other products on the market, if you are looking for a wood look that are waterproof sort of speak. There are many LVT (Luxury Vinyl Tiles) in wood planks and porcelain wood plank tile looks to choose from. It is almost impossible too match the color and look of existing hardwood floors with these products. It is best to select a look and color that compliments rather than matching.

In terms of going with something like ceramic, porcelain or stone tiles, I have no problems with using a different flooring in bathrooms from main areas. It is a whole different room, it brings interest, as long as you keep the colors coordinating with adjacent rooms and preferable the rest of the house for continuity.

A 5x6 bathroom can support using, most sizes of tile 6x6, 8x8, 12x12, 13x13, 12x24 size tiles. There are plenty of mosaic sheets that are small like 1x1, 2x2, 3x3 or even subway sizes. PLEASE NOTE: Make sure they are rated as FLOOR tiles and not walls tiles or they will break.

In terms of transitions from wood to tiles, you can build up underneath the tile so it is the same level as the wood height. I like to use Schulter Stripping in between.

You can also find a reducer strip or T-molding too match the wood species and color that transitions down if it ends up being a different height.