# Painting over weakly bonded paint



## duluxordie (Jun 4, 2020)

Some clown had used a cheap water based paint over oil without good prep.


It doesn't peel in sheets, unfortunately, so it's hard to remove. It comes off in little flakes when scraped with a putty knife, video attached (sorry for the shakycam).


To strip all the walls like this would take soooo long. Obviously I'd rather paint over it. But I'm afraid that this weak bond between these existing paint layers will remain weak, yielding an easily scratched surface.


Is it possible that new primer applied over this paint will soak through and bind the underlying layers together? Do I have to use a water-based primer, or maybe some specialty primer?


----------



## SS_painting (Jan 11, 2020)

Palm sand what you can. Whatever is left has bonded to the substrate. Prime accordingly. Then finish

Sent from my SM-G950W using Tapatalk


----------



## Woodco (Nov 19, 2016)

Gardz.


----------



## futtyos (Aug 11, 2013)

*Welcome to Paint Talk*



duluxordie said:


> Some clown had used a cheap water based paint over oil without good prep.
> 
> 
> It doesn't peel in sheets, unfortunately, so it's hard to remove. It comes off in little flakes when scraped with a putty knife, video attached (sorry for the shakycam).
> ...


duluxordie, welcome to Paint Talk. What is your paint related trade or field? That being asked, I wood second what Woodco said about Gardz. Gardz will penetrate cheap, chalky paints and help bind them to the surface underneath. If you brush some water over the paint and you can see the paint darken a bit - just as water will darken a white t-shirt - then Gardz will likely be able to penetrate the paint you have shown in the photo. Good luck,

futtyos

IBTMTTO


----------



## Vylum (May 12, 2016)

interesting. what the recoat time of gardz? also if somethings really bad can you stack a bunch of coats on and it works miracles ?


----------



## Woodco (Nov 19, 2016)

You can recoat gardz an hour later. There is no miracle primer.

Gardz is not a sure thing either, but it can help in a pinch.


----------



## Joe67 (Aug 12, 2016)

I'd third (?) the gardz as the best bet (tho not a sure one as there aren't any). If you've never used it, I suggest a respirator.


If there's time in the budget, apply some gardz to small area that you know is bad. Come back the next day and see if it passes the fingernail test.


----------



## SS_painting (Jan 11, 2020)

Would applying multiple coats of Gardz do anything extra? Or would that just be a waste of time, money, and energy? 

Sent from my SM-G950W using Tapatalk


----------



## cocomonkeynuts (Apr 14, 2017)

I would spec lightly pole sand with 150 grit then guardz


----------



## Joe67 (Aug 12, 2016)

SS_painting said:


> Would applying multiple coats of Gardz do anything extra? Or would that just be a waste of time, money, and energy?
> 
> Sent from my SM-G950W using Tapatalk



No "expert" on Gardz, but I've used it. If the first coat was thorough, then I doubt it would help. It kind of acts as a super-sealer, so the second coat would just sit on top of the first. I'd imagine this can easily depend on how porous the surface is. But in this case, I'd bet on the side of a waste...


One way to find out would be to just inspect after it's dry. Like other clear primers (MadDog or PrimeRX) it leaves a rubberyish kind of sheen behind. Light at an angle shows it, and with a hand-rub you can feel it. So if a post-1st coat inspection shows any inconsistencies a 2nd might be in order.


Others smarter and/or more experienced with Gardz may chime in.


----------



## futtyos (Aug 11, 2013)

*Gardz TDS*

Here is the TDS for Gardz:

https://www.rustoleum.com/~/media/D...GDZ-01_GARDZ_High_Performance_Sealer_TDS.ashx

Here is an exerpt from same:

GARDZ appears
milky blue-white during the application but dries water clear.
Properly sealed surfaces should have a uniform sheen.
Reapply to areas that have been missed or lack sufficient
coating. 

futtyos


----------



## Redux (Oct 27, 2018)

Before messing with a primer I’d try steaming it with a wallpaper steamer followed by scraping it off with a flexible joint knife...it might come off in big sheets/effortlessly with steam, but then again it might not..


----------



## Woodco (Nov 19, 2016)

I dont believe in multiple coats of gardz, myself. Its similar to a waterborne stain. The first coat penetrates, the second coat sits on top. I think youd be better off doing one coat, and doing subsequent coats of something like scuff-x or precat epoxy or something very tough, in hopes that the strength of the topcoat can offset the lack of adhesion... Still a crapshoot though...

An oil primer might work better than gardz in this situation though.. Run some 80 grit sanding over it, and with any luck the primer can find some micro holes in the paint to fill in and stick to the surface below. Then put two three coats of something tough, and tell the client to be careful, as theres no promises of good adhesion. 

And be careful if you do steam it. You can turn the sheetrock into mush if you overdo it.

What about peel stop triple thick? That might make a bulletproof layer, like rolling elmers glue on the wall. I wouldnt do it on cabinetry, but walls might work.


----------



## MikeCalifornia (Aug 26, 2012)

Guardz is a bad idea in this situation. Go straight to CoverStain oil based primer, don't sand anything until its primed. Skim coat any imperfections, then paint.


----------



## Joe67 (Aug 12, 2016)

MikeCalifornia said:


> Guardz is a bad idea in this situation. Go straight to CoverStain oil based primer, don't sand anything until its primed. Skim coat any imperfections, then paint.



Some elaboration would be nice...


----------



## futtyos (Aug 11, 2013)

*Why Gardz is best choice for chalky & porous surfaces*

Once again, from the TDS:

"Penetrates deeply into porous surfaces" "Binds down chalky surfaces" "Strengthens soft texture finishes"

...all of which seem to describe what duluxeordie is trying to do. 

I like Joe67's idea in post #7: "If there's time in the budget, apply some gardz to small area that you know is bad. Come back the next day and see if it passes the fingernail test."

It is good to remember that Gardz is a rip off of Scothc Paint's Draw-Tite. Draw-Tite was fashioned after a concrete sealer. 

I used to strip and was (actually acrylic finish) floors. One floor I did early on was somewhat worn and beaten down. After stripping and rinsing off the old finish, I applied several coats of acrylic floor finish, but the floor continued to look dull. I went to my local janitorial supply and and conferred with my janitorial guru, Jack. He explained that I needed to use a sealer first, then the finish coats of acrylic would sit on top and shine like it should. He was right. I re-stripped the floor, then applied 2 coats of sealer. My top coats of finish shined brightly over the sealer.

My guess is that duluxeordie's paint is a cheap water-based paint. What better to use over it than a water based sealer? Gardz is thin as well, so it will soak in right through the paint, and without any sanding beforehand. At least that is my observation based on my use of Gardz over the years. I wonder if an oil or solvent based sealer or primer would do the same or just stay on top.

If it were me, I would do a section like Joe67 said to do, then come back the next day and give it the fingernail test.

duluxeordie, if you do decide to try a Gardz on a section of paint, watch carefully to see if the surface gets darkened by the Gardz just as plain water would slightly darken a t-shirt. If this happens, the Gardz is probably soaking right through the cheap paint and adhering it to the surface underneath.

futtyos


----------



## MikeCalifornia (Aug 26, 2012)

Joe67 said:


> Some elaboration would be nice...



Here's my elaboration:


My advice works and is the standard for what that little video showed. The video did not have a film that is peeling, so its one coat of latex over oil. If you just leave it alone and coat over it with oil, you will have little to none prep after it dries. Sure Guardz may work, but what if it doesn't? Most of the responses do not know what would happen. I like Guardz and have used it to solve some crazy problems, but more sheen related than peeling paint.


----------



## futtyos (Aug 11, 2013)

*Joe67 post #10*



MikeCalifornia said:


> Here's my elaboration:
> 
> 
> My advice works and is the standard for what that little video showed. The video did not have a film that is peeling, so its one coat of latex over oil. If you just leave it alone and coat over it with oil, you will have little to none prep after it dries. Sure Guardz may work, but what if it doesn't? Most of the responses do not know what would happen. I like Guardz and have used it to solve some crazy problems, but more sheen related than peeling paint.


MC, you may be right about about coating it with an oil something, but I am inclined to try out Joe67's suggestion (Post #7) of doing a small area with Gardz, then come back the next day and give it a fingernail test.

What oil based product would you use on this?

futtyos


----------



## Redux (Oct 27, 2018)

Below are a couple of photos of failures with Gardz & 024 oil primer used on latex over oil. The Gardz did not penetrate the existing latex film to any noticeable degree and did not enhance adhesion between the existing oil & latex in the slightest. 

Prior to repainting, there were no visible cracks/alligatoring, and the drywall was not subjected to moisture/humidity, being located in dry locations. The alligatoring was due to the existing latex delaminating from the oil due to added internal stresses from subsequent coatings and increased dry film thickness. 

The procedures implemented were to give the existing latex a quick once-over mechanical sanding followed by Gardz then 024. Minor repairs were performed over the 024 and finish coated with Regal select. After all the wasted effort, I ended up re-rocking two of the three rooms. 

Before doing the rooms, I strongly suspected that both Gardz and oil primer wouldn’t work. One of my employees recommended I try Gardz. Not saying it wouldn’t work in some instances, but it didn’t work for me..I might add that the rooms were not for a paying client, had they were, I would have removed the latex and charged accordingly.


----------



## Woodco (Nov 19, 2016)

The more you know....


----------



## CApainter (Jun 29, 2007)

Mechanical sanding degrades a compromised coating even further. 

Short of following best painting practices and completely remove the flakey coating, I would just cross my fingers, start the motor on the seat of my pants and launch into the unknown of Hillbilly chemistry and physics with a pile of steamy down home painting experience thrown in for good measure.


----------



## finishesbykevyn (Apr 14, 2010)

Whatever doesn't come off with a good 100 grit pole sand probably ain't coming off. I also vote for cover stain oil primer. Or even INSLX Stix may be a good bet for bonding purposes. I've done this tons ove the years with success. 
2 Coats of primer may be a good idea just for some build to fill in imperfections.


----------



## Redux (Oct 27, 2018)

This past winter I tackled the last of 4 rooms from my prior post which had been previously painted with latex over oil, trying something I saw on a DIY YouTube video. 

I wet the walls with slightly diluted household ammonia & soap. It did soften the latex enough that it was able to be scraped off with the similar ease of removing a wall covering. It took about an hour per every 100 sq ft.


----------



## futtyos (Aug 11, 2013)

*Gardz and non-porous surfaces*



Redux said:


> Below are a couple of photos of failures with Gardz & 024 oil primer used on latex over oil. The Gardz did not penetrate the existing latex film to any noticeable degree and did not enhance adhesion between the existing oil & latex in the slightest.
> 
> Prior to repainting, there were no visible cracks/alligatoring, and the drywall was not subjected to moisture/humidity, being located in dry locations. The alligatoring was due to the existing latex delaminating from the oil due to added internal stresses from subsequent coatings and increased dry film thickness.
> 
> ...


Now that you describe this scenario, and reading over the initial post, it does seem that if the oil based paint underneath the latex is non-porous (i.e., shinier than a flat sheen), Gardz will not likely be effective as Gardz is basically designed to soak through and into porous surfaces and bind them down.

Painting latex over non-porous, non-scuffed or non-primed oil based is a big non no. In fact, there is a word that I use to describe this situation - vandalism!

Even so, I would try a spot test with Gardz as long as this situation is present, just so see if it works.

futtyos


----------



## Redux (Oct 27, 2018)

futtyos said:


> Now that you describe this scenario, and reading over the initial post, it does seem that if the oil based paint underneath the latex is non-porous (i.e., shinier than a flat sheen), Gardz will not likely be effective as Gardz is basically designed to soak through and into porous surfaces and bind them down.
> 
> Painting latex over non-porous, non-scuffed or non-primed oil based is a big non no. In fact, there is a word that I use to describe this situation - vandalism!
> 
> ...


Unfortunately the vandalism was on my own home, the previous owner coating over what appeared to be Satin Impervo with latex..I hadn’t noticed it until oil priming and installing grass cloth in my master bedroom. Within a few weeks, the grass cloth developed huge air pockets where the existing latex pulled away from the oil. I ended up having to gut the room & re-rock/re-trim. It was a very time consuming and costly fix..as were the other rooms..

In agreement with sampling out and testing the Gardz..


----------



## Woodco (Nov 19, 2016)

Redux said:


> Unfortunately the vandalism was on my own home, the previous owner coating over what appeared to be Satin Impervo with latex..I hadn’t noticed it until oil priming and installing grass cloth in my master bedroom. Within a few weeks, the grass cloth developed huge air pockets where the existing latex pulled away from the oil. I ended up having to gut the room & re-rock/re-trim. It was a very time consuming and costly fix..as were the other rooms..
> 
> In agreement with sampling out and testing the Gardz..


Sorry to get off the subject, but paste supposedly doesnt stick for chit with modern oil primers anyway. What exactly were you using?


----------



## Woodco (Nov 19, 2016)

Also, whats everyones thoughts on simply skimcoating the wall? Redux says he rerocked three rooms. What do you think would happen if you just skimmed a 1/8" of mud on the whole thing, then gardz that? Technically, there would be a weak layer in there somewhere, but think a good layer of mud just might be enough to solidify it against any future failures. Thats my theory, anyway. If anyone has experience in that, I'd love to know the outcome. It'd be a hell of a lot easier than rerocking, I know that much.


----------



## futtyos (Aug 11, 2013)

*What surface is underneath?*



Woodco said:


> Also, whats everyones thoughts on simply skimcoating the wall? Redux says he rerocked three rooms. What do you think would happen if you just skimmed a 1/8" of mud on the whole thing, then gardz that? Technically, there would be a weak layer in there somewhere, but think a good layer of mud just might be enough to solidify it against any future failures. Thats my theory, anyway. If anyone has experience in that, I'd love to know the outcome. It'd be a hell of a lot easier than rerocking, I know that much.


I would think that the weak link in the OP's scenario is the bond between the oil based paint underneath (which I am assuming is of an eggshell or higher sheen and which was not scuff sanded prior to top coating) and the latex painted over it. This weak link will not go away unless the latex paint is removed. I was thinking that Gardz would soak through and help bond the latex to the oil, but Redux and others here have disabused me of this idea. Gardz is for sealing porous surfaces. If the underlying oil based paint was a flat, Gardz might work, but since it appears that the underlying surface has a sheen and probably has not been scuff sanded prior to the application of the latex topcoat, I don't see how Gardz will adhere to the non-porous oil based paint. If this is the case, anything other than removing the latex paint and prepping the oil based paint for topcoating - OR - drywalling over the damage, will not work as the oil-latex bond will cause adhesion problems with anything applied other than screwed on sheets of drywall.

On a lighter note, I am doing a repair job at a large 2 story house, re-inserting and patching drywall squares that were cut out for repairs and left for re-insertion as well as some ceiling water stain problems. The stairs here are 1.5 stories. I woke up today with my left knee ballooned out and sore. 

futtyos


----------



## Joe67 (Aug 12, 2016)

Woodco said:


> Also, whats everyones thoughts on simply skimcoating the wall? Redux says he rerocked three rooms. What do you think would happen if you just skimmed a 1/8" of mud on the whole thing, then gardz that? Technically, there would be a weak layer in there somewhere, but think a good layer of mud just might be enough to solidify it against any future failures. Thats my theory, anyway. If anyone has experience in that, I'd love to know the outcome. It'd be a hell of a lot easier than rerocking, I know that much.



The last time I had an "impossible wall" it was from widespread plaster failure brought on by an older leak in the roof of the house. You know how it is with plaster - start knocking and see what falls off and then keep chipping 'til you find what adheres. On this one, It seemed clear it would be most of it.


Anyway - long story short - no gutting. We got the drywall guy in who just did 1/4" sheetrock over the whole thing. 



Perhaps Redux was thinking something like "might as well gut it and redo the electrical too" or whatever. That can sometimes make a lot of sense, depending. But if that's not a thing, I'd say just slap 1/4" over it all and prime/paint as normal.


----------



## Redux (Oct 27, 2018)

Woodco said:


> Sorry to get off the subject, but paste supposedly doesnt stick for chit with modern oil primers anyway. What exactly were you using?


I primed with 024 which was allowed to cure for a couple of weeks, followed by the manufacturer’s recommended wallcovering-specific acrylic primer which was compatible over all surfaces as per TDS. 

The point of failure was the existing latex over oil interface, and not the acrylic over the 024..whenever I do use 024 under a wall covering installation followed by a wall covering specific acrylic primer or even a porous flat paint as specified under some wall coverings, as a precaution, I’ll hit the 024 w/#150 to create some tooth..haven’t had a call-back yet using the 024 followed by an acrylic, but there’s always a first time for everything..


----------



## Redux (Oct 27, 2018)

Joe67 said:


> The last time I had an "impossible wall" it was from widespread plaster failure brought on by an older leak in the roof of the house. You know how it is with plaster - start knocking and see what falls off and then keep chipping 'til you find what adheres. On this one, It seemed clear it would be most of it.
> 
> 
> Anyway - long story short - no gutting. We got the drywall guy in who just did 1/4" sheetrock over the whole thing.
> ...


The reason I opted for gutting & re-rocking vs using 1/4” drywall was I wanted to keep the trim consistent and not have to fabricate extension jambs. I also would have needed to cut the copper heating pipes and move the baseboard heaters out a 1/4”, as well as install box extenders on the receptacles and switches. It was probably more time efficient having removed the drywall rather than dealing with the above mentioned. It’s amazing how one chitty paint job could cause so much work..btw, the house was only 7 years young..


----------



## Joe67 (Aug 12, 2016)

Redux said:


> The reason I opted for gutting & re-rocking vs using 1/4” drywall was I wanted to keep the trim consistent and not have to fabricate extension jambs. I also would have needed to cut the copper heating pipes and move the baseboard heaters out a 1/4”, as well as install box extenders on the receptacles and switches. It was probably more time efficient having removed the drywall rather than dealing with the above mentioned. It’s amazing how one chitty paint job could cause so much work..btw, the house was only 7 years young..



Indeed. Sometimes the gutting does make more sense.


----------



## Woodco (Nov 19, 2016)

futtyos said:


> I would think that the weak link in the OP's scenario is the bond between the oil based paint underneath (which I am assuming is of an eggshell or higher sheen and which was not scuff sanded prior to top coating) and the latex painted over it. This weak link will not go away unless the latex paint is removed. I was thinking that Gardz would soak through and help bond the latex to the oil, but Redux and others here have disabused me of this idea. Gardz is for sealing porous surfaces. If the underlying oil based paint was a flat, Gardz might work, but since it appears that the underlying surface has a sheen and probably has not been scuff sanded prior to the application of the latex topcoat, I don't see how Gardz will adhere to the non-porous oil based paint. If this is the case, anything other than removing the latex paint and prepping the oil based paint for topcoating - OR - drywalling over the damage, will not work as the oil-latex bond will cause adhesion problems with anything applied other than screwed on sheets of drywall.
> 
> On a lighter note, I am doing a repair job at a large 2 story house, re-inserting and patching drywall squares that were cut out for repairs and left for re-insertion as well as some ceiling water stain problems. The stairs here are 1.5 stories. I woke up today with my left knee ballooned out and sore.
> 
> futtyos


I was suggesting skimcoating over the whole thing, not gardzing it. Give the whole wall an 1/8" of new mud. After the skimcoat is done, then gardz the raw mud like usual.


----------



## Woodco (Nov 19, 2016)

Redux said:


> I primed with 024 which was allowed to cure for a couple of weeks, followed by the manufacturer’s recommended wallcovering-specific acrylic primer which was compatible over all surfaces as per TDS.
> 
> The point of failure was the existing latex over oil interface, and not the acrylic over the 024..whenever I do use 024 under a wall covering installation followed by a wall covering specific acrylic primer or even a porous flat paint as specified under some wall coverings, as a precaution, I’ll hit the 024 w/#150 to create some tooth..haven’t had a call-back yet using the 024 followed by an acrylic, but there’s always a first time for everything..


Gotchya. I didnt realize you acrylic primed over the oil afterwards.


----------



## finishesbykevyn (Apr 14, 2010)

Woodco said:


> I was suggesting skimcoating over the whole thing, not gardzing it. Give the whole wall an 1/8" of new mud. After the skimcoat is done, then gardz the raw mud like usual.


You think mud would stick better than a good bonding primer? I don't know about that. I'd be afraid it would come off in sheets.


----------



## Woodco (Nov 19, 2016)

finishesbykevyn said:


> You think mud would stick better than a good bonding primer? I don't know about that. I'd be afraid it would come off in sheets.


Im not talking about sticking to the wall, Im talking about giving the wall a whole new surface.


----------



## duluxordie (Jun 4, 2020)

Zinsser Peel Stop Triple Thick seems more specifically for this situation than Guardz and is roughly 10% more expensive, so shouldn't it be considered over Gardz?


I'm getting good ideas for stripping paint quicker here. I know acetone dissolves latex nicely but haven't tried applying it wholesale to entire walls.


----------



## finishesbykevyn (Apr 14, 2010)

Woodco said:


> Im not talking about sticking to the wall, Im talking about giving the wall a whole new surface.


Yep, but the mud would still have to have a mechanical bond. It would work, but I would hit it with a bonding primer like coverstain first. Also @Fructose, I don;t think Gardz is designed to bond to oil, although it might..wouldn't be my first choice.


----------



## Woodco (Nov 19, 2016)

finishesbykevyn said:


> Yep, but the mud would still have to have a mechanical bond. It would work, but I would hit it with a bonding primer like coverstain first. Also @Fructose, I don;t think Gardz is designed to bond to oil, although it might..wouldn't be my first choice.


The mud would go on top of the latex layer, so there would be no adhesion issues there, and no need for bonding primer. I really dont think you'd even need a bonding primer over oil. Mud sticks. The reason you can scratch paint off the oil, is that its so thin, you can break through the paint layer all the way to the oil, then pull it up more. You're not gonna break through a nice thick layer of mud to get to that weak oil/latex layer with a fingernail, and if you do, that would be wall damage anyway, so its irrelevant. Its encapsulated. I deal with floated walls all the time. The mud is ON THERE. It would take a chisel to get to the paint layer.


----------



## jacob33 (Jun 2, 2009)

The only way I would do mud is if the whole wall had mesh over it. They sell mesh tape that is 3 foot wide. I have applied it over the entire wall and than skim coated it. First you spray glue on the wall. Lowes sells spray bottles of it. Spray it on put the mesh up and than skim coat it. It makes the wall really strong and there is a layer bonding all across the whole wall. 

Thats just my 2 cents probably not worth much more than that.


----------



## futtyos (Aug 11, 2013)

*Post #28*



finishesbykevyn said:


> Yep, but the mud would still have to have a mechanical bond. It would work, but I would hit it with a bonding primer like coverstain first. Also @Fructose, I don;t think Gardz is designed to bond to oil, although it might..wouldn't be my first choice.


See my post #28.

futtyos


----------



## Wildbill7145 (Apr 30, 2014)

finishesbykevyn said:


> @Fructose



Sorry, this part did make me laugh. I think Kevin was saying that Futty is a sweet guy. Such a nice thing to say during these troubling times.


----------

