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Interior priming, spotty coverage

3290 Views 17 Replies 8 Participants Last post by  Brushjockey
After priming over previously painted walls I question if the primer coat is sufficient. It appears to not be perfectly even, and Im concerned this will effect the final top coat..?
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Why did you use a primer? When going latex over latex, a primer usually is not needed.
When you say primer- realize you are saying problem solver. Know your problem, know your primer.
There is not usually an adhesion problem, or a porosity problem unless it is greasy, dirty or heavily patched.

You are probably safe to go to your paint unless any of the above problems were present.

A quick sand to knock off any bits on the wall is always a good idea .
Why did you use a primer? When going latex over latex, a primer usually is not needed.
When you say primer- realize you are saying problem solver. Know your problem, know your primer.
There is not usually an adhesion problem, or a porosity problem unless it is greasy, dirty or heavily patched.

You are probably safe to go to your paint unless any of the above problems were present.

A quick sand to knock off any bits on the wall is always a good idea .
I used a primer in interest of hiding the bright colors for better coverage of the new color. Ive always been told using a primer is the best option even over painted walls... Sounds like you feel otherwise, interesting!
Primers are not for covering colors- they actually have less pigment- more resin than paint. paint is best to just switch colors.
Primers, as i said- solve other problems. I carry at least 5 different primers- each do different things.
Primers are not for covering colors- they actually have less pigment- more resin than paint. paint is best to just switch colors.
Primers, as i said- solve other problems. I carry at least 5 different primers- each do different things.
What exactly would I use a primer for besides repairs or new drywall/wood? Im repainting the entire house, if I skipped priming that could save money and time! Whats your opinion on spot priming over drywall repairs and then switching color?
Primers:
Some seal irregular porosity ( ie new rock or patched walls)
Some seal stains ( many choices in oil, shellac or waterborne depending on the kind of stain)
Some are for adhesion ( which depends on what you are adhering to- and what is the end product)
I could go on, but it would be a book.

This is one of the things that I think separates the DIY from the pro- what to use when.
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AJ, primers, as BJ said, are problem solvers. I have raw wood or drywall, and since finish is not designed to bond to those substrates, that's a problem. Primers are designed to bond to bare substrates, and have a higher resin content, but have less hide. Finishes have higher pigment content that gives the hide. There are numerous conditions and problems that can give a painter a flawed finish, either aesthically or functionally, and numerous types of primers to correct for those.
I've never used primer to hide color on a color change, and that's either on my own jobs or when I've worked for other pros, and that accounts for about twenty five years of rolling, or as BJ says, "rubbin" walls.

Unlike BJ, I carry three basic primers, Zinsser Cover Stain, Zinsser (shellac)BIN, and a regular everyday latex primer, usually Zinsser 123 or a BM or Sw primer. I think Cover Stain is the most universal primer, it seals and bonds, unlike Kilz, which doesn't bond. It can be used as a full prime both interior and exterior, unlike BIN which is full interior spot exterior. Though they may be spec'd for drywall, neither Cover Stain (oil) or BIN are ideal for priming new drywall, in which case I'll use the 123. However, if I have a job where I'm doing a lot of new drywall, I'll buy a conventional dedicated drywall primer. In some cases when I have a lot of new pine trim to prime I'll use full BIN to head off what nuclearnerd is suffering. There are a lot of variables, which could, yes, be a book.

I'm doing some Hurricane Sandy aftermath work in Ocean City, NJ. I'm working for the owner of the building/business, while a new tenant is remodeling undamaged office areas. The new tenant's contractor is doing his painting, and he's done nice carpentry work. However, when it comes to painting, he's a DIY. Part of their job is a stairway, which had wallpaper that was stripped, over plaster. The walls were not washed and were caked, and I mean caked, with wallpaper paste. Yesterday, his guy was rolling drywall primer on those walls. He had a problem, which he failed to recognize. And he didn't know he needed a special primer, either an oil quick dry or Gardz, to act as a barrier between the water soluble paste and water based topcoat. Now, his final finish, and the primer, is at great risk of complete failure as the paste can cause the whole job to end up a crackle finish and flake off. That's the difference between a pro and a handyman/DIY. The walls are such a mess that I recommended rehanging paper to the tenant, but he was being sentimental on paint, and his contractors cheaper paint bid. I told him, twice, that he needed an oil prime and extensive plaster repair and that paper was the easier/least cost way to go. Now his shortsightedness, and stinginess, may end up costing him dearly. Always hire a pro. I don't necessarily like it, but I'll struggle to hide my glee when the finish goes crackle and pop. Always hire a pro.
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On just about every wall there are drywall repairs. In this case does it make sense to prime everything or just spot prime?
On just about every wall there are drywall repairs. In this case does it make sense to prime everything or just spot prime?
You have received outstanding advice from jsheridan and Brushjockey.

Using their sage logic, ask yourself the question, "Do I have a problem?" Yes, you must prime those bare spots or they will flash through the finish coats. Are the walls glossy? You now have a problem with adhesion. Your new paint may not stick to SLICK, SHINY walls. In that case you will need a bonding primer.

If you are painting satin over a satin or flat over flat all you need to do is spot prime with a drywall primer and apply 2 coats to the walls. No need to prime the entire wall.
To JS' list of fav's of primers to keep on hand, I see his 3 and add:

Gardz- clear penetrating sealer for dozens of situations
Universal Sanding sealer ( desterated shellac) - use on finishing wood

His :
Bin
Cover Stain
Zin 123 ( or 123plus/Smart Prime)

This is a very comprehensive list of problem solvers..

There are many others to replace some of the above or are more for special situations.
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I've been wanting to try the Gardz, but it's not too readily available in my market. I'd like it for the wallpaper to paint barrier to get away from the Cover Stain, which is a quicker recoat time, but heavy on the odor.
J, I just picked up some Zinsser primer for the stains...

Im going to switch to only spot priming instead of priming everything. Just picked up some sherwin william emerald paint, hopefully its worth the extra money!
"Ive always been told using a primer is the best option even over painted walls..." AdrenalineJunkie

That's the main 'problem', right there - as I see it. What one sees as a 'problem' isn't to others - or the 'problem' has a different solution altogether. Here the OP didn't know he/she had a problem situation at the outset; it became a problem eventually, as the results weren't as expected.

So the question is: why did the OP prime the wall? The answer is that really it took no primer at all...it took paint.
I've been wanting to try the Gardz, but it's not too readily available in my market. I'd like it for the wallpaper to paint barrier to get away from the Cover Stain, which is a quicker recoat time, but heavy on the odor.

http://www.homedepot.com/buy/zinsser-1-gal-problem-surface-sealer-2301.html

+ SW should be able to order it for you
I used a primer in interest of hiding the bright colors for better coverage of the new color. Ive always been told using a primer is the best option even over painted walls... Sounds like you feel otherwise, interesting!
On just about every wall there are drywall repairs. In this case does it make sense to prime everything or just spot prime?
You are giving conflicting info here. As Brushjockey mentioned Primers are not for covering colors. Any patched areas will need 3 coats or they will not match the existing wall. It is always best to have your first coat be primer and then a coat of paint (both of those can be on just the areas patched), and then a final coat over the entire wall. One coat of primer and one coat of paint is rarely enough, especially with an eggshell or semi-gloss paint.
SW doesn"t handle any Zinnser products, but Ben Moore does. My local HD doesn't carry it and won't order it, but yet they carry Zinnser, figure that out. I ended up finding it at just a small paint store in the area.
You are giving conflicting info here. As Brushjockey mentioned Primers are not for covering colors. Any patched areas will need 3 coats or they will not match the existing wall. It is always best to have your first coat be primer and then a coat of paint (both of those can be on just the areas patched), and then a final coat over the entire wall. One coat of primer and one coat of paint is rarely enough, especially with an eggshell or semi-gloss paint.
I can see how it comes across conflicting... When you say three coats, do you mean spot prime and then two full coats on the entire wall or just the spot primed area?
..read his post again..
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