Painting - Kilz + Flat Paint = Shiny part

Hi,

I am painting my living room and started with the ceiling. I took the ceiling HVAC diffusers out and noticed some discoloration where moisture messed up the drywall's appearance.

So, I reached for my Kilz, which was oil-based, rolled it on, and then waited about an hour and a half or so. I painted flat paint over it and now where I applied the Kilz is shiny.

How can I fix this problem? I am planning on doing a second coat tomorrow.

I wouldn't panic until the 2nd coat of flat paint is applied.

That part is shiny because it was sealed by the Kilz,unlike the rest of the ceiling.I hope another coat of flat fixes it,but it might not.If you're getting a glare on the ceiling from a window,you might always see the shiny part.
Worst case scenario,you might have to prime the entire ceiling.

Latex paint dries slower over kilz. Often it just looks shiny because it hasn't dried yet while the unsealed surface nearby has soaked up the paint allowing it to dry faster.

Let it dry, if it still shows another coat of flat should fix it.

Oil needs much longer than that to dry before coating with latex
(oil/water=not good)
You run the risk of other problems also

Oil needs much longer than that to dry before coating with latex
(oil/water=not good)
You run the risk of other problems also

There are MANY oil primers that work quite well under a latex coatings. And MANY of these oil primers are very quick dry for topcoating. Kilz, ProBlock, Zinnser line etc can be ready for topcoating in as little as 30 minutes. (Depending upon humidity, air temp etc)

In many cases, oil is the PREFERRED primer depending upon surface conditions. In the exterior oil primers on steel is usually better at holding out rust stains, but then are best topcoated w/latex.

On wood, (exterior) oil primers DO require longer dry times before painting w/latex, but in fact seal the wood more effectivly as they soak into the fibers rather than float on the surface.

Regardless of what the can says, I'd let it dry longer than 1 1/2 hrs to avoid this, and other problems

Oil primer/ Latex topcoat DOES NOT = bad

You may feel more comfortable waiting more than 1 1/2 hr for repaint. However, it will not give the OP better results. Unless his living room was a chilly 45F and relative humidity of 90% that is about 45 minutes longer than required for a successful job.

The culprit most likely was a cheap flat applied before he/she got into the home. The primer sealed up this area, and so the "shiner" was very noticable. As Marksr pointed out, a second coat in all likely hood will aleviate the problem.

By reading your original response the OP would step away with the impression that somehow the oil primer on its face is not to be used w/ latex topcoat.

Thanks for your prompt response though. And I hope the OP has gotten his problem fixed.

Slickshift basically said you can't mix oil and water. Well, if the oil primer wasn't dry, the h/o DID mix oil and water. If the oil primer was dry, then there was no mixing.

Hi all,

Another coat of flat fixed it right up. Now I am having an issue with roller marks, but I know what I did wrong. Thanks for the advice!