How can I deal with non square walls when installing a countertop with backsplash?

Question

I am converting the huge upstairs master suite in my house into a studio apartment. I have built a kitchenette in one of the dormers. Everything is coming along and looks great. But when the counter was dry fitted into place, we realized the corners of the dormer were not square. The counter is flush against the window but is 5/8" off the wall at each corner. I had planned on installing a subway and mosaic tile back splash but don't know how to deal with the gap. I love the way it has turned out but all the wind has been knocked out of my sails with this problem.

Answer 1

If you are installing a tile backsplash, just sort the issue out on the tile substrate. Depending where you want the tile surface, either overlay backerboard and shim to correct the gaps, or rip out the current wall surface and replace with backerboard, shimmed to correct the gap once the tile is installed (which may mean an even gap before the tile is installed, again depending how you intend for it to look.)

It's a small area, should not be too difficult/lengthy a process.

Counter looks a wee bit high going by the window opening...if that's an egress window you may fail inspection for partially blocking it.

Answer 2

In my kitchen, there's a wooden cap molding which hides any gap between the backsplash and the wall, stained to match the cabinets. I can't immediately tell whether it was scribed to follow the wall, simply nailed down tight, or if the wall was leveled in that area before the cabinets were installed... but if you're willing to have the backsplash's reveal be a bit uneven, this would probably suffice to hide the problem.

Answer 3

For a small runout on laminate countertops I like this method. I assume this is a laminate counter top. First cover the top of the back splash with a one inch width of masking or green painting tape. Run a pencil held vertically so it transfers the bulging section of the wall to the top centre section of the back splash. In this case the centre section of the backsplash. Trim along the line so the end result is the middle top of the back splash will be slightly thinner than the ends. This will allow the counter top to move back slightly reducing the spaces on both the left and right sides that were being held away from the wall by the centre section. Repeat a tiny amount each time to gradually make the back sides come closer to the wall reducing the space. Use a very fine tooth metal cutting blade in jigsaw take your time, do not let it jump up losing contact with the surface to reduce chipping. The back splash is very thin along the top so it will cut easily. I suggest green painting tape to be applied so the pencil mark shows up. It will also protect against chipping and scratching. Reapply painting tape for each cut. Caulk the back splash where it meets the wall to eliminate any remaining narrow gap.