Asked on Jan 08, 2019

How do I backsplash over wavy drywall?

Jeremy Wagner
by Jeremy Wagner

Just got new countertops installed to find out my wall that the backsplash will be installed is is wavy, is it easier to use mud and build up the wall or use the backsplash mortar to build up the wall? Or just cut the drywall out and replace?

Terrible countertop install but it is what it is
Yes they cut the drywall out to make their countertop fit, yay Home Depot
  12 answers
  • William William on Jan 08, 2019

    For minor differences in the wall you can use the thinset to create a smooth finish. Place the thinset on the wall then butter the back of the tiles with thinset and set in place.

  • Joy30150932 Joy30150932 on Jan 08, 2019

    It would be much easier to level it out with the drywall spackle.

  • Mani Mani on Jan 09, 2019

    I had the same problem on my living room wall. I used drywall mud. If the wall is really wavy, put the mud on in layers, letting it completely dry before adding next layer. Use a level or straight edge to determine when the wall is even.

  • Crystal Meyer Griffith Crystal Meyer Griffith on Jan 09, 2019

    The quick, easy treatment is to buy a sheet or two of 1/4" backer board and screw it into the studs. This stiff board is made for tile applications. You will need to tape and mud any joints. Check YouTube for assistance.

  • Mona Blake Mona Blake on Jan 09, 2019

    Drywall mud is the best way to level it out. After you mud the wall and install the tiles, grout everwhere except the bottom. Run a bead of caulk along the bottom.

  • Seth Seth on Jan 09, 2019


    if you replace the drywall with cement backer board remember that your wall studs are probably not completely flat (might be bowed or crowned) causing the waviness. You will need to fur/shim the studs in order to get a flat surface for whatever material you use. Check out this youtube.

  • Frank Frank on Jan 10, 2019

    What kind of backsplash are you installing and what's the biggest gap behind the counter?

  • Jeremy Wagner Jeremy Wagner on Jan 10, 2019

    Thank you for all y’all input, Seth that’s my biggest worry about replacing the drywall is working on the studs. Frank, the biggest gap is only 3/16 but they also cut the drywall out to fit the countertop under the drywall about 3/16-1/4”

    • Jeremy Wagner Jeremy Wagner on Jan 10, 2019

      As far as the type of backsplash it is 12 x 12 squares with slim rectangles, that’s all I know about the type

  • Seth Seth on Jan 10, 2019

    You should be okay filling dips with thinset if only 3/16" deep. More than that and you run the risk of the tile popping. A 12x12 is pretty heavy and a deep layer of thinset may not hold that much weight. You might be better off filling the dips with joint compound first.

  • Jean Jean on Jan 18, 2019

    I had the same problem and did not want to mess with the drywall. I used small tiles 1 x 1 marble, on sheets. The "waves" were not noticeable at all when it was finished.

  • I think you'll be just fine here as the mortar and tile will hide many secrets.

  • Deb K Deb K on Jan 09, 2024

    Hi Jeremy, you can easily fix this with drywall filler, nobody's drywall is perfect so don't feel like it's just yours 😊Once you use the filler you should put a coat of primer over it to set it.