Sanding off latex paint / texture with the Planex ?

[AIPDX]

I am looking for advice from fellow FOG members.

In one of my bedrooms there is a persistent smell from a paint job which I completed nearly two years ago. Chemical smell from paint which does not want to go away is a rare occurrence, but not unheard of. There are long treads on the internet about this kind of issue. Different fixes are suggested, reported results are mixed. Replacement of drywall always works (and some people actually went down this path), coating of walls with multiple layers of shellac-based BIN primer (which is the best odor blocker available) sometimes works, air filters or "household solutions" like exposure to fumes of chopped onions or vinegar never work. I tried baking the paint off with heaters (no result) and exposure to ozone for 4 hours of generator time (significant improvement, but some odor on a much lower level remained). My wife does not want me to repeat ozone with a longer exposure (this time, I would use 8-12 hours) because the residual ozone smell takes about a month to completely disappear, and my wife finds it very annoying even in small concentrations.

To make the long story short, I am considering the idea of sanding the offending paint off the walls. I am dealing with  (greenish on surface) drywall, splatter texture, at least 4 layers of old (nearly white) paint/primer, and then new smelly (orange) paint. I should have good visual cues of how much I sanded off before damaging the drywall itself as color changes from orange to white to greenish. The house is from post-lead construction period, so it is all plain and simple latex paint.

I plan to use the Planex for this task. In fact, I would not even consider sanding the paint if I did not have a Planex. Since it is indoors and since I have hardwood floors which I definitely do not want to expose to anything potentially damaging, chemical paint removal is out of question.

I searched on the FOG and in the Internet, but did not find much, if anything, specific about removal of paint. I made an experiment on a small area of wall in a bathroom which I was remodeling this year and got the impression that I can sand the paint down to drywall with good control. I gathered that if I do not sit on the same spot for a long time and watch the color of the wall as it is being sanded, I can see when I get through the paint.  However, it was just a square foot of the wall surface, while the task at hand is the whole room.

I wonder if FOG members have experience with such task and could recommend type of abrasive / grit size, Planex settings, time which it might take to finish the whole room. or provide other helpful guidance which could help me to reduce the risk of mistakes.

Thank you!

 

[cblanton42]

Hello,
    I don't know how big the room is but I'd really consider removing the drywall and re-hanging new instead. You most certainly can remove it way quicker than sanding it all down to the paper layer and not do some sanding damage needing repairs.    I've spent a lot of time patching/sanding/smoothing drywall and in hindsight several times wished I had just gutted the place and started with new drywall instead of the time spent making the old look acceptable.  Other factors may make it unfeasible but just a thought from Seattle.  Good luck!
 

 

[rizzoa13]

You won't be able to just sand it down and get a consistent enough surface to just paint over it. You'll likely need to do some Spackling even if you went the sanding route and even then you'd have trouble getting a consistent sheen.

If your really against re-rocking it is consider sanding it pretty rough with like a 60 grit to give it some tooth and then skimming Spackle across the entire surface. Coat with a stain blocking primer and I can't see any odor getting through that.

If you wNt to go that route PM me for some tips on skimming if you'd like.

 

[AIPDX]

Thanks! Yes, I fully expect that I will have to prime and spray texture after that, maybe also skimcoat before priming if there is too much damage or exposed tape. I am not very receptive to the idea of drywall replacement. I can install drywall with a reasonably controlled amount of dust, but drywall demolition on the second floor is bound to be a major mess around the house. My wife would prefer the ozone option to sheetrock mess for sure...

I plan to try sanding the walls on the weekend. Got P80 Granat specifically for this task. I was hesitant to buy a rougher grit because of the risk of oversanding. In my little test which I described earlier, I used P180 which I used for drywall sanding. That created virtually no damage, but it was kind of slow.

In principle, the task at hand is similar to that of removal popcorn texture from the ceiling, with the difference that I deal with relatively flat texture covered with at least 6 layers of paint.

UPDATE SATURDAY, AUG 29: Started sanding with P80 Granat. Paint turned out to be much more stubborn than I expected. The initial results are promising, removal is very controlled and visual feedback is excellent, but removal rate is way too slow. At this rate, I am guessing it might take me in the ballpark of 12 hours to remove paint from walls of an approximately 10 feet x 12 feet room. Ceiling would be a major workout even with the harness. So, I ordered a rougher grit abrasives, P40 and P24. They should arrive on Wednesday.  Since I do not know what will work best, I ordered two sizes at the same time. The price bites (especially with P24). Too bad Festool does not sell grit assortments or smaller packages. Not every Planex owner is a professional contractor who needs abrasives in bulk.

For the fun of it, I also tried P180 Granat. Surprisingly, I did not find that the paint removal rate was much slower (as far as one can compare very slow with another very slow), but P180 clogs with paint quite a bit, while P80 does not.  So, as expected, P180 is definitely a no-go, and P80 is also not aggressive enough, at least for the initial removal.

 

[AIPDX]

For the record, and for the benefit of those who might ask the same question in the future. I tried sanding the painted wall with P24 paper, with the same result of marginal success. There is some slow removal, but it would take hours and hours to get a room done. P24 does the job a little faster than P80, but not by much.

I decided to try Rotex 125 for the same task, and got much better results. Upon some experimenting, I discovered that the task of sanding paint requires a lot of pressure on the sander. Planex, due to a large size of its sanding head and its design, is not made to press hard on the sanding disk. Without pressure, neither Planex nor Rotex are successful. Sanding paper, even P24, has hard times gripping on the paint and removing small pieces.  When you press the Rotex against the wall, you start seeing removal and a fairly rapid progress.

Unfortunately, I have to conclude that Planex is totally not suited (nor designed for) for sanding paint off the drywall with a shallow (splatter) texture.

I have no experience with popcorn removal, but I start wondering if it would even work if the ceiling is painted.

 

[cblanton42]

  Thanks for the update, I always like to hear how things work out!  Sorry to hear the plan didn't work using the Planex, it would have been a lot faster if it did.  Just to clarify, did you sand down the whole room with the rotex after you decided against using the Planex or are you still trying to figure it out?
      If the popcorn on the ceiling has been painted it really makes that job quite difficult because water can't get to the stuff and dissolve it, if not, a spray bottle of warm water and a scraper on a long pole gets it off real quick and as you can guess, is real messy.  Wear a mask, could be asbestos based, a single room won't kill you but err to the safe side!
Good luck!
CB

 

[AIPDX]

Thanks! I had to put this project on a temporary hold due to other things that had to be done in the house and a family trip during the Labor day weekend. I will post an update as I get back to the project. I expect to finish it within the next two weeks or so.

 

[AIPDX]

Let me just finish this thread, since the project has been done. After I had done both walls and ceiling, I made the following learnings:

1. Latex paint is very hard to sand. It feels like sand paper just slides on top of it, without creating much damage, or does it very slowly. The best way to overcome this is to use a lot of pressure. The thicker is the paint, the more pressure is needed. Pressure is difficult to achieve with Planex. I found that Rotex RO125 which I had at hand was much more efficient tool for this task. Its removal rate was probably 5-10 times higher on the walls which had at least 5-6 layers of paint on it (accumulated over time), and 2-3 times higher on the ceiling, which likely had 2-3 layers of paint. It helps to both press fairly hard on the Rotex, and to move it around at a fairly fast rate, to complement its own rotation/vibration with linear motion which seems to be efficient in chipping off small flakes of paint. I connected it to the dust extractor from Planex using a standard green vacuum hose.

2. Removing paint from walls with Planex was practically impossible - or it would take unreasonable long time, even with P24 abrasive. You see some progress, but it is impossibly slow.

3. I had better success with the Planex on the ceiling where paint was thinner and texture a little rougher. Using Rotex on the ceiling was a major workout. Planex with the harness made this job easier. It was not fast, but steady. It took probably several hours in total to do the ceiling in a small to medium size room. I made breaks often, so it is hard to calculate the total actual work time exactly. Planex is not exactly a light tool, even with the harness.

4. The texture was light splatter on the walls and knock-down on the ceiling. I do not have experience to compare how removal efficiency depends on texture. I would think that it may be easier to break through peaks on a rougher texture, and then removal would get more efficient, but I may be wrong.

5. The risk of damaging the drywall was quite low. If you move the tool around, you will see when you hit the paper on the surface of drywall, and it takes at least a few seconds sitting on one spot to get through the paper. If you pay attention, you most likely will not damage the drywall itself. I had just a few relatively small spots where I got through the paper, and it was predominantly during the learning curve part of the job. Taping at the joints between sheets of drywall was not damaged, with the exception of one small area which yielded to pressure on the tool - but it was easy to fix.

6. The problem with Rotex is that it is hard to control when it comes to sanding near the corners. To prevent risk of creating more damage than it was worth, I decided against sanding the corners and left about 1-2 inches of painted surface around corners intact. I figured, if I remove 95+% of paint, my (residual smell related) task will be achieved.

7. I had to coat the walls and ceiling with drywall compound to make them flat again, and they sprayed texture. The walls now look better than they looked before. Since I had old paint left in corners, and there were a few areas which were sanded more than the others, I ended up with not quite a skim coating, I troweled around 70 Lbs of drywall compound on the walls and ceiling. It looked so clean and even after that that I was hesitant to even spray texture on it, but our house is all textured, so it had to be done for consistency.

8. Labor-wise, it was probably a similar amount of work to what it would take to take the drywall down and install the new one (except that in my case, heat isolation in the attic is a foot of loose powder sprayed all over the attic. It just rests on the drywall ceiling below it, so taking drywall off the ceiling would be a MAJOR undertaking - unless on looks forward to getting buried by all this isolation falling down from the attic and then go through the mess of replacing it with fresh one). The amount of dust and mess was much less than if I were to replace the drywall, and I did not need a drop box to get rid of the removed drywall. The cost of sanding and recoating was also lower than the cost of drywall + drop box (if Planex and Rotex are not counted as expenses related to the job). Realistically, I used up about 10-15 sheets of Rotex P24 paper, a few sheets of Planex P24 paper, and a sheet of P220 for touch sanding after skim coat. [of course my actual cost was higher than a few sheets per grit because abrasives are sold in bigger boxes and I doubt I will ever use the rest] And then, a box of drywall texture compound and paint and primer and all that plastic that went on the floor to protect it. And several plastic liners for the dust extractor.

I finished painting on Sunday, so the impact on smell will be seen after paint dries completely.

I took some pictures along the way, but after looking at them decided that there is not much added value in posting them.

 

[robkelle]

Hey [member=28086]AIPDX[/member], thank you for taking the time to post this through to the end of your project. Almost a decade later, I'm facing a similar situation, but I just want to take down the painted texture coat because of inconsistency. If a Planex had done the job as I was hoping it might, I would have tackled a good portion of our house. This has either spared me a lot of work or at least set expectations much lower!

 

[AIPDX]

Since my post (a long time ago!), I had another occasion to test my skills of removal of latex paint and texture off drywall. I want to make sure that my long post which you answered to is not misunderstood. The wording of your message suggests that there may be some confusion. You definitely need a Rotex, or any powerful and agressive sander, to tackle this task. Texture is soft and easy, but latex paint is surprisingly stubborn (and, evidently, fairly slippery for the abrasive disk). One has to use a low grit sandpaper and press the tool into the wall pretty hard (expect a good workout for the arms). Planex has too large sanding disks and is not designed to exert enough pressure. One can sit on one spot and wait forever, it is just way too slow. Since I have the original Planex, which was rather large and heavy, holding it at one spot for a long time was not a very enticing idea.

So, on the second project, I used Rotex (125 mm) from the very beginning, then put a thin layer of drywall compound, then a light touch with Planex, then sprayed texture.

It is not possible (or very difficult) to remove paint / texture from about the last inch from the corners.

Regarding the speed of the project... It depends on how strong your muscles are. For me, even a small room took two days. I just cannot press the Rotex against the wall or against the ceiling with a significant pressure for a long time and need a lot of rest breaks.

 

[alltracman78]

latex paint is surprisingly stubborn (and, evidently, fairly slippery for the abrasive disk).

Latex is rubber.
Rubber is a pain the arse.
The vibration just shakes the paint around instead of digging in.

It's just like trying to remove frozen bolts in a rubber bushing.