Can I use drywall mud instead of mastic on a backsplash wall?

no I would not recommend

Drywall mud would be used to smooth out a drywall wall. Then you sand smooth and prime. Mastic or thinset is used to adhere tile to the wall. If you have existing tile it's best to remove the tile, patch any damage with drywall patching compound, and prime. Tiling over existing tile adds more weight and both tiles can tear off the wall. Some have used peel and stick tile which is lighter but any imperfections in the backsplash will transfer to the peel and stick. Also it will add thickness to the wall and any electrical outlets/switches would need to be shimmed out.

Brenda

Everything I am finding says not to use dry wall mud for backsplash install and says it will dry and cause cracking of the tile or other backsplash materials. Here is another idea I found for you

https://homeguides.sfgate.com/mortar-vs-tile-adhesive-installing-backsplash-62974.html

For backsplash-yes. For tile -no. It is what holds the tile to the cement board.

If you are using tile, no, it won't hold.

Here is a great video from This old House on how to install a backsplash properly. https://www.youtube.com/watch?v=mNDISOzizbY

Hey Brenda! I would not use drywall mud for tiling, but you can buy already mixed thinset that makes it just as easy to use as drywall mud! I tiled a kitchen wall for the first time and it was pretty easy using the premixed thinset!

https://theinspiredworkshop.com/how-to-tile-a-kitchen-wall/

Hope this helps! Have a good one!

Mastic or thin set is an adhesive. Drywall mud is not adhesive. They are not interchangeable.

No, drywall mud is a plastering type product for drywalling, and mastic is an adhesive product for holding tile on the wall or floor. Buy the pre-mix type and the right knotched trowel for creating the furrows to hold your tile securely to your wall. Then you will need grout, sanded or unsanded, to use to fill in the grooves between the tiles that is applied with a rubber float and then wiped with a large car sponge.

No it will crack you need tile glue then grout the tile if the correct products are not used it will crack and the tiles will fall off

Mastic is a strong glue that will help keep the tiles secured. Drywall mud does not have the same effect

They are two totally different products, you really need to use mastic instead.