1

paint not sticking to wall

Background:

  • In a bathroom that had some mold/mildew.
  • Existing paint on walls appeared to be eggshell latex on top of oil. The latex had crazed/cracked but was adhering.
  • Existing paint on ceiling seemed to be gloss latex.
  • Existing paint on door trim seemed same as ceiling.
  • Temperature about 62F and humidity about 50%

Day 1: Mold on walls sprayed with 25% acetic acid, an hour later wet sanded with 25% acetic acid and scotch brite, an hour later sprayed with 25% acetic acid and wiped down. All other parts of wall wiped with 25% acetic acid. Similar treatment for ceiling except only mold/mildew hit with 25% and rest hit with 5% (it seemed fine).

Day 1/2: dehumidifier run in bathroom. Humidity sensor consistently 50% or below.

Day 3: Zinsser Mold Killing Interior/Exterior Multi-purpose Water-based Wall and Ceiling Primer applied to all surfaces. Coated fine, filled in crazing.

Day 4: nothing

Day 5: 2 coats Zinsser Semi-gloss Perma-White Tintable Latex Interior Paint + Primer about 3 hours apart on ceiling and door trim. Adhered fine, looked good. Also dabbed some on top of wall primer in a few places where more color seemed to be coming through. Again, adhered well.

Day 6: Sherwin Williams tinted quart of the above Zinsser Semi-gloss Perma-White, which they don't sell. Rep worked with me to try to come up with a color using one of their paints as a model (ProClassic; I have his tint formulation label if that helps). He did a great job. However, when I went to apply the paint, it would not stick well. Going over it with a roller pulled the paint right back onto the roller (new roller). I tried with a previously used roller, same result.

In a bit of a panic, I wiped as much paint off the walls as I could with shop towels and used a putty knife to scrape off more. Some that came off even took the primer with it. What remains seems to be adhering for now.

Questions:

  • Did the tint applied at Sherwin Williams change the adhesion of the paint, or should I suspect something else?

  • How should I handle the remaining paint?

2
  • What is "Day 6: SW tinted quart"? Southwest?
    – FreeMan
    Dec 19, 2023 at 14:46
  • 1
    Sherwin Williams is SW. I'll update the question to resolve the ambiguity. Dec 20, 2023 at 15:56

2 Answers 2

4

It seems the problem was indeed the tint. Two sources of evidence here.

  1. Zinsser customer support

Our Zinsser Watertite is designed to be tinted only to specific colors and using some coloroant systems like Benjamn Moore Preview, Charisma. We do not recommend custom tint with this tint base. We cannot tell you for sure how the paint might have been affected It may very well be the coloring tints used and the amount of tint used affected the properties of the Perma White.

  1. Sanded down the custom tint paint, used the same primer, and then used Perma-White tinted at Lowes. This is the first coat, but the second coat was also fine:

reprimed wall first coat

Reading between the lines, it appears that SW CCE tinting system is water based but Zinsser recommends Universal tint which has different properties. The failure seemed to be an application failure due to the tackiness of the custom tinted paint rather than a failure to form a durable coating, as the custom tinted paint, when dry, seemed to be "good". Here is the doc on the tech sheet:

perma white tech sheet

Why didn't I get the paint tinted at Lowe's in the first place? The rep at the desk at 730pm on a Tuesday night told me he couldn't tint it when I asked him to match a color. That sent me down the rabbit hole of having it tinted somewhere else.

1

When priming or painting over previously painted surfaces, especially substrates that have a higher sheen paint it is advisable to use TSP to clean and then degloss the surface with a deglosser or by pole sanding.

Another thing, not all primers are created equal. You must use a primer designed for previously painted surfaces.

My advice would be to let it dry/cure, pole sand the walls with 120 and then make sure you've got a primer suitable for the application.

Zinsser Permawhite is tintable so it is unlikely that the tinting compromised the paint.

1
  • This seems like good general advice, but the primer label covers the first two points: the existing paint was eggshell and the primer can be used over existing paint and light mold without cleaning (and I did clean and wet sand with scotch brite). label pdf I've put this question in to Zinsser and will report back. I may do a larger area of the wall with untinted white to see if I get the same result Dec 16, 2023 at 17:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.