Aspiring contractor and DIY'er here. So I'm learning a lot along my journey and trying to soak in as much knowledge as I can. Live and learn!
So I'm working on a kitchen that has some fairly wavy walls, and trying to set myself up for success on some old framing. I've decided not to tile all the way to the ceiling, but would like to throw in a wrap around (3 wall ~ 30" high) subway tile backsplash on these walls. My back wall needs some amended electrical work and there's a large bow in the middle preventing a flush scribe for my counter tops so I plan to rip out the sheet rock the span/height of the tile only and truing up the studs for a flat substrate on this bowed out wall.
The thing is, these other two walls run into a window and door jamb and only have mild fluctuations say maybe 1/4" or less over the span of the wall, so I'd like to entertain building out the wall or filling in gaps before tiling. Only thing is, I can't seem to find any definitive resources on floating mortar/adhesive out there, seems to be a old school/"feel" skill. But I'm curious as to what my options might be, and have a few questions for the pros, if you'd all be so kind. For reference, this is subway tile going over primed w/paint sheetrock:
1) I absolutely know that the proper and ultimately easier way to tackle this is to completely plumb/level the framing, which will be done on one wall, but the other two are simply not an option. Given that these waves/variances in the wall range from about 1/4" (MAX) and below, I'd like to try and build out the wall with some type of compound in these spots. Does it make more sense to build out the wall in certain areas, and then tile adhesive over that? Or is it simply enough to go fat on the tile adhesive and fill things in as I go, back buttering and spot tiling?
My plan ultimately with these wavy walls is to make a grid with marks both up and down before hand, so as to have many visualized areas for low spots and dips that could use some filling in. I've heard of various compounds to build out the wall, but would also require a more glue-ish mastic type of tile adhesive. What do you all think? Any help would be greatly appreciated. Much thanks in advance.