I am repainting a bathroom that includes trim with a high gloss. The house is old (1924) and the existing paint may have lead in it. There was a remodel in the '80s, but I can't guarantee the current paint was applied then.
My local paint store advised against sanding to take off the gloss, because of the lead risk. They recommended a "liquid sandpaper" product which I applied. However, the first coat of the new paint did not stick (I've been stripping it back off for the last couple of weekends). The paint store also advised I did not need a primer, which I now believe was a mistake.
How can I get the new paint to stick to the old?
Best Answer
Rather than just seal in paint that might be lead-based, especially as you mentioned that you're stripping off the bad coat, it might be worth finally just removing it so you don't have to go through these concerns in the future. (especially if you don't have kids now, but think you might in the future, so you can get the dust over and done with).
New York has some recommendations for removing lead paint. The important thing is to keep it from becoming dust and getting spread around the house, which just makes things worse. I believe there are some chemical paint strippers that can be used with lead paint, although that website didn't mention any. I also found mention that Massachusets used to require licensed contractors and require it to be disposed of as hazardous waste, so it might be worth checking before you attempt this.
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If you were going to attempt this without stripping it all off, I'd follow the New York guidelines (contain the area), wet sand to rough up the surface, then prime it and re-paint.
Oh ... and you can also get test kits for check for lead paint. Odds are, being gloss and trim, it's more likely though, and even if the top coat isn't, there might be lead in an older coat.