I know for a fact that the builder of my house did not prime the ceiling. (About 5-minutes of painters tape loosely applied stripped the ceiling down to the drywall paper.)

I am painting a room with a sky-blue ceiling, with the intention of covering it up w/ 2 coats of SW Classic99 Flat Extra White.

Would it do any good to prime the ceiling at this point, or should I figure the at least three coats of existing paint is a suitable "primer substitute"?

I am already priming the walls, as I had to skim quite a few patches, and where I didn't skim, the walls are tutti-fruti colored.

SirWired

 

If you already have the primer out, go ahead and prime the ceiling. Primer is great for hiding darker colors. You will get a better application of ceiling paint without the worry have multiple coats to hide the blue.

 

skyblue and tutti fruit: why paint over - that's be back in style in a couple hundred years.

if i though i was going to apply 2 coats i'd prime and then do 1 coat of paint instead.

 

With cheap builders paint and no primer, you have a disaster waiting to happen
It might takes months, it might take years
It might be fine even for a repaint...for now
But this time, next time, sometime, it will fail

Extra top coats of paint at this point won't help...well it will help hasten the failure, but I assume you aren't going for that

It can be saved with a penetrating primer
A coat of Zinsser's Gardz will penetrate through the builder's paint, and help it seal in and adhere

No further priming is required after that
Top coat with a premium Ceiling Paint
Don't skimp here...you need the adhesion
The Classic will be fine...but if possible, I'd suggest a ceiling-specific paint

But if you skim coat any repairs, or are doing a massive color change, you may want to prime over the Gardz
It's not pigmented very well
It;s sort of like a watered down Elmer's Glue
-it may be actually...lol...maybe that's why it works so well for adhesion issues

 

Slickshift, I appreciate the advice, but I primered (with SW Latex ProBlock) just before I saw your post. (oops)

Will the Guardz still do any good, or did I just prevent it from soaking through to the wall?

SirWired

 

The Pro Block is pretty good stuff
At this point, I wouldn't Gardz it
The Pro Block is technically more of a "blocking" primer than a "adhesion" primer
But I wouldn't try and Gardz over it
Let it dry and cure as much as possible (at least 24 hours) before painting it

 

Heh. Letting it dry 24 hours won't be a problem. My wife and I have spent all day yesterday just putting the finish coats on the trim.

We are also having our handyman come in and do some drywall work in the room before the finish coats go on. (My pathetic attempts at skim coating took a long time to do and look like junk.)

And yes, the drywall patches will be primed.

As to why I am using the Latex ProBlock: In this case, I want to make sure that whatever crap paint the previous homeowners put on the wall does not bleed through, and when I told the paint store that I had "bold colors" and scattered stains throughout the house, this is what they gave me. For the remaining ceilings, I'll use Gardz (or the SW equivalent, PrepRite Drywall Conditioner).

SirWired