I have removed a wall and upper cabinet, replacing some sheetrock. I have skim coated and sanded the existing walls and removed the "popcorn" ceiling. My question is: do I need to primer the walls & ceiling before I spray "knockdown texture?
Something is needed to seal the new drywall. Primer is much cheaper than paint. The basic rule is if you want a wall to look uniform, you have to prime it first.
If this is a paint + texture can, when left unprimed, the drywall will suck all the paint from the texture into the wall, leaving an uneven mess behind. If you're going to paint after applying the texture, I'd prime in between as well; the natural unevenness from the spray will lead to splotchiness.