Painting Over Old Paint

Zendik

What does it take to paint over old paint? I'm hearing al this stuff like to walls need to be scrubbed with TSP? Or will a few layers of primer do it? This is an interior situation.
Thanks for any answers!

Flikka

Need some more details.

When was it last painted?
What type of paint is on the wall, what type of paint are you putting on the wall? Latex/Oil?
What has the room been used for....lots of grease from cooking?

Cheers
Mary

Zendik

Hello, Mary,
I believe last it was painted was ten or more years ago and the house has been vacant for the last three or so years. I believe it is just a latex that is on the walls at this time and we want to use a latex for the final paint. The kitchen has been completely re modeled with new sheetrock so ther is no grease problem there. The rest of the house, living room, bedrooms etc are the parts we are wanting to paint now...
Thanks!!

Flikka

Who is telling you to use TSP and why? Typically TSP is suggested when there is grease, heavy dirt or unknown substances on the surface of the wall that won't come off with normaly washing. When you're prepping a surface for paint you want to make sure that you have the best surface possible to apply the paint for the best finish possible. Makes for happier clients. At the very least you should give it all a good wash, sanding and prime with a high adhesion primer before painting, as the last known paint job is 10 years plus.

Good luck
Mary

P.S. Your welcome.

PlainPainter

Why not just sand the walls, and the dust, and then if you feel you want to give them more prep - give a good TSP washing, or a rag soaked with Denatured alcohol and a good rub. I wouldn't resort to priming - unless there is something real funky.

Tmrrptr

Zendik, you are in Honolulu?

Humidity and moisture are your problem.

Yet, if a residential wall surface is clean and dry, (and not painted w something exotic, like epoxy), there should be no problem painting over it without using a primer. Primer can resolve possible problems with unknowns, and less than desirable circumstances, before applying a topcoat.

A quick-sanding, to help with adhesion, could identify bad areas on the walls. It allows you to focus... You'll notice if a bunch of slough drops from a particular part of the wall, or doesn't, from others.

TSP is also used to etch the surface somewhat, as in liquid sandpaper...
(which I don't like, a lot).

I'd give it a quick shot with a pole sander, if you're in doubt.
r

skyhook

If you sand and don't prime, you will not get an even finish. Had a painter insist on sanding only, no wash, all the stains came through, primed it and stains still came through, painted it twice after that. Would have been so easy to just wash it first. Needless to say I fired him.

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PlainPainter

I disagree - if there is nothing wrong with walls why would you prime? And unless you have grease or something funky - why would you wash? Rooms such as bathrooms with all the toiletries and hairsprays - need a good wash on the walls - and perhaps a child's bedroom that has loads of gunk. But nicely maintained living room walls? I think a wash is overkill - and I wash more than most painters - I wash after wallpaper removal, walls with obvious soot, around door knobs of all the doors, bathrooms, kitchens - but formal dining room walls? Forget it!

Paul_R

I wash some walls if they appear or feel greasy, ie kitchen walls. Bathroom walls can be a toss up. Seems like there are usually fingerprints around the light switch, or the wall above the toilet where the mister put his hand while taking a leak. A wet rag with some dish detergent usually removes the offending substance. Also kids rooms can have various waste products and such stuck to the walls, this also should be cleaned. Prime with spray primer of your choice if you have crayon or magic marker to cover. Also there may be black shoe marks in closets. They can be spray primed as well.

Hope this helps, and Happy Painting, Paul.