Painting - Paint over paper adhesive

Ceiling was previously papered. It was removed but adhesive remains on the surface. Can I paint right over the adhesive? The adhesive came off the walls easily but the ceiling is tougher. I removed about one square foot and it took about half an hour. People at paint store said that steamer would not help.

Second problem: There is a black stained area about one square foot that probably was a bathroom leak once but is now dry. I am planning to paint with Zinzer anti-mold paint then top coat with ceiling paint. Think this will work?

Welcome to the forums!

It would be best to remove all the adhesive. It should come off with water and lots of elbow grease:eek:
If you must paint over the adhesive, you need to either prime with an oil base primer or zinnser's gardz [which is water based] sand when dry and then paint.

You might try and see if any of the black will wash off, almost any oil base primer will seal the stain although stuborn stains might require 2 coats or the use of the utlimate stain sealer - pigmented shellac [like zinnser's BIN].

There will never be a better time than now to get the adhesive off, that right now. If you paint over it, every change in humidity could cause potential mildew and peeling problems. Cover the floor, get a garden sprayer and put a little remover in it with hot water, spray a section of ceiling, let it soak in and keep it glossy wet, and steel wool the paste off with coarse steel wool. It's not that hard. Agree on the black stain, Zinnser Bin.

Bill

On the ceiling, you can use gel remover which will not drop all over your head etc.... Roll it on like you would paint. You will still need to cover the floor, but it will be much less messy.

You can attach a spackle blade to an extension pole to scrape off the glue if it is heavy duty clay adhesive. There are spackle knives that have acme threaded handles which will work also if you can locate one.

Finish off with warm water rinse using a sponge mop.

I am never in favor of priming directly over wallpaper glue. But oil primer will seal off residual glue after you have done your best to remove all the glue (Gardz will too - as per Zinsser, but I would prefer oil to a waterbased product for this as an oil stain kill will prevent any staining from bleeding too). Ventilate well when using an oil stain blocker as the odor can be quite strong.

Don't prime or paint over the mold. Use a commercial mold / mildew remover. Protect the carpet well because most of these contain bleach which will ruin your carpet if they drip on it. If the mold is bad it may require proper mold remediaton.