Latex primer over oil based paint?

We are planning to paint our walls which have oil paint on them since we moved in. The current paint is oil based, semi gloss and apparently only has one coat applied to the walls. I've already begun sanding with a 120 grit sanding screen. Now the roadblock is I've read a ton of things about not using latex paint on oil paint which is understandable. But my question is, can i use a latex primer on the sanded surface (preferably KILZ2) or do I have to use an oil based primer?

 

Welcome to the forums!

Some of the new latex primers claim that they will bond to oil base enamel but I'm not convinced. I know a solvent based primer will adhere long term! Kilz 2 is a poor stain hiding primer and has been reported to have adhesion issues - I never use it. You can't go wrong using an oil base primer [most any brand] over your existing oil base enamel.

 

Thanks!

The thing I've read about oil primers is their smell, and that's the factor I'm particularity worried about, which is why I'm sort of leaning towards the use of latex primers instead. What are a couple of good latex primers that could be named?

 

Being an old school painter I'm not all that up on what latex primers that claim to be ok over oil enamel are available [I always use a solvent based primer for those jobs] PPG has a grip rite [?] primer that supposedly will do the job. Zinnser's Bondz or Bullseye water based primer might also be an option.

Opening a window and using a fan to exhaust the fumes does a decent job of getting rid of the odor.

 

Zinsser Bonds is pretty good stuff, but it's unlike any paint or primer I have ever used. Looks and stirs like a heavy paint, but goes on almost like a semi transparent stain. I like that it sands to a powder, one of the things I always look for in a primer.

 

I'm defiantly leaning more towards Zinnser Bullseye 1-2-3 rather than KILZ now. Another question I have is how would a "Paint and Primer in One" work on an oil based surface?

 

I wouldn't depend on a paint/primer in one coating to adhere! IMO it's more a marketing ploy than anything else. Most interior repaints don't require a primer. The only time primer is needed on repaints is when there is either an adhesion concern [your case] or stain or color hiding is needed.

 

IMO, your best bet is to open all the windows and set up a fan or two to create airflow and stick with the tried and true method of oil based primer over oil based paint before using latex paint.

I don't believe the all-in-one products actually contain any primer; like Mark, I believe that's just a marketing ploy.

 

Neither Kilz 2 nor Zinsser 1-2-3 specially say (by the mfg) that they are recommended for use over an oil based paint... so don't know why you would even consider either one.

Zinsser Bondz *is* specifically recommended by the mfg for use over a variety of substrates, including over oil based paints and glossy surfaces. And it is water based, no odor, which is what you wanted.

Kilz "original" would also work but you said you wanted to avoid oil and odor.

 

X knows of what he speaks so if you want to try the Bondz, I'm sure it will do the trick. Otherwise, I stand by my last post.

 

Thanks for all the quick replies!

I think IF the paint is oil...I will pick the oil based primer. The reason I say IF is because I did a little experiment earlier today while i was sanding. I applied some of the new latex paint (1 coat) in a small area which was unsanded or cleaned with TSP. Returned 2 hours later to find that the paint had dried.

At this point I could tell something was up, the paint seemed in contact with the supposedly "oil based paint" on the wall. So then i took my thumbnail and went at it, I slowly scraped it with my thumbnail then just scratching at it. The paint, did not come off the walls one bit...

And If i recall correctly, a couple years ago we had a small leak in the bathroom on the second floor. On the celling a small "bubble" had formed which contained the water. I did a bit of research and i have only seen this taking place is on latex paints and not on oil based ones.

Does this mean the paint is actually latex and not oil?

 

Try this - http://www.doityourself.com/forum/pa...latex-oil.html

 

Yep, just tried that but with nail polish remover both on the ceiling and the walls, paint for sure CAME OFF onto the rag. And the finish did not look polished or shiner, it actually looks like it lost its gloss (dull) and smudged compared to the rest of the wall now.

 

I didn't know that nail polish remover and denatured alcohol were the same thing.

 

I had to use nail polish remover due to the fact I didn't have denatured alcohol on hand. I was surprised that it worked too.

Assuming now that the paint is latex both on the wall and celling, would sanding and a primer still be required?

 

The point is that your nail polish is so strong that it will likely affect BOTH oil paint and latex paint finishes. Denatured alcohol will only affect latex paint. Which is what the test is trying to determine.

 

I think nail polish remover is made from acetone with maybe a little lacquer thinner which will dissolve most oil base paints. Denatured alcohol won't touch oil base paints but will soften/remove dried latex. You could also use 'goof off' or 'oops' to remove/dissolve dried latex paint.

 

I'll try goof off - the miracle remover and update you on the results.

 

Got a small can of goof off pro remover, applied it to the surface and paint came off onto the paper towel! It also felt a little sticky afterwards, with the same effect of a duller finish.

 

Sounds like latex paint What made you suspect oil base paint to start with? Is the paint extra shiny? if so, a light scuff sand is in order before you repaint.

 

Yep, it was the semi gloss and it would not come off easily at all. Would it be okay if i just skipped over the sanding and cleaned the walls and applied primer?

 

If its latex, you dont need a primer. You should always lightly sand before painting a wall to knock off any imperfections from the last coat of paint. And you really only need to wash if the wall is dirty or has some residue that needs to be cleaned off, like maybe hair spray.

 

As stated above it's always good practice to sand prior to recoating. It doesn't have to be a heavy duty sanding, just a scuff sand to remove/minimize any imperfections and promote better adhesion.

 

Glossy paints can be hard to get the next coat to stick to and roughing them up a bit with a light scuff sanding usually helps a lot.

 

Thanks for all the help!

Looks like we're getting a step closer to painting, I'll let you know how it turned out!

 

Update:

Finished this project a couple days ago, a little later than i expected but the outcome is completely worth it! The new paint looks amazing with no roller marks or streaking. I did apply primer to the walls and ceiling to help the paint adhere a little better. Thanks for all your guys help! Next future project...the kitchen cabinets!

 

It's always nice to finish a project and the bragging rites that go along with it

You might find this useful when you get ready to tackle the cabinets - http://www.doityourself.com/forum/pa...t-repaint.html