Help prepping wall for paint

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Attempting to prep basement exterior foundation walls for paint. From the picture you can see that it has 2 existing layers of paint. House was build in 1948 so who knows how old the paint is. Paint is flaking off and just nasty.

We've been using a wire brush and lots of elbow grease but it's not coming off like we had hoped.

The plan is to wire brush, Thompson water seal, then paint.

Any help or ideas how to remove this tough old stuff?????


 
I speak from experience on scraping layers off old wood window frames, not brick.

Not sure how it would work on that rough surface, but I like Bahco carbide scrapers for scraping off old paint. I guess the hardness of tungsten carbide is so much greater than steel that it pops paint that a steel scraper just drags across.

Otherwise, a 5" disc sander by Makita with some 30-grit discs, but it'll make a lot more dust and in my experience goes about as fast as the Bahco scrapers.
 
If it's on there that good, paint over it.

Personally, I would not try to paint over Thompsons water seal. Your paint should seal enough on it's own.

What paint do you intend to finish with? Elastomeric?
 
Originally Posted By: expat
If it's on there that good, paint over it.

Personally, I would not try to paint over Thompsons water seal. Your paint should seal enough on it's own.

What paint do you intend to finish with? Elastomeric?



The paint is a behr brand "brick masonry" that was recommend by the Home Depot paint guy.
 
Be careful about lead in paint and asbestos in building materials on a house of that age.

Can't help you with your paint challenge, but I would research if the Thompsons is appropriate. It doesn't seem so.
 
Originally Posted By: expat
If it's on there that good, paint over it.

Personally, I would not try to paint over Thompsons water seal. Your paint should seal enough on it's own.

What paint do you intend to finish with? Elastomeric?


X2.

If the paint is that difficult to take off, there is no reason to remove it. I'm assuming you plan on applying some type of spackling to make a smooth surface before you paint? If so, then the spackling will even out the old paint.

Are there signs of water problems on this wall? If no, there is no need for a sealer. If yes, sealing from the inside will never give you a long term fix. If you were planning on using Thompson's to seal out staining that has came through in the past, then Kilz is a lot better choice.
 
Originally Posted By: BHopkins
Originally Posted By: expat
If it's on there that good, paint over it.

Personally, I would not try to paint over Thompsons water seal. Your paint should seal enough on it's own.

What paint do you intend to finish with? Elastomeric?


X2.

If the paint is that difficult to take off, there is no reason to remove it. I'm assuming you plan on applying some type of spackling to make a smooth surface before you paint? If so, then the spackling will even out the old paint.

Are there signs of water problems on this wall? If no, there is no need for a sealer. If yes, sealing from the inside will never give you a long term fix. If you were planning on using Thompson's to seal out staining that has came through in the past, then Kilz is a lot better choice.


The basement has gotten water in the past. Before the bought the house the basement was repaired by " US Waterproofing" and a sub pump was installed. Over the summer we had MASSIVE record setting rains and flooding. The basement was thankfully bone dry. Regardless this is why were going to paint and not frame and drywall everything.
 
I've had good luck with DryLok paint by UGL on basement block applications. I think you would be disappointed with the Thompsons product.
 
You could very likely be releasing lead and asbestos when scraping those materials. Test for both before proceeding. Use proper PPE.

DryLok is the way to go.
 
Do NOT use water seal. Use UGL drylock or Thoro seal. You can add latex paint to tint color. If you are concerned about adhesion Thoro systems makes a bonding agent called acryl60 which will make the paint stick to masonry. You mix it with the paint. I did 2 coats of drylok on my basement in 1998. Still dry as a bone. Use a masonry brush to paint it on. Put cardboard on the floor to catch the mess.

You can get acryl60 at Ace or Doitbest
 
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As stated, if the paint won't come off with a wire brush leave it. I wouldn't water seal it. I'd use a type of Dry Lock paint. Rememer you're painting the interior of the basement, not the exterior. No amount of paint of sealant is going to be able to withstand the pressure of water seeping in. In other words, you can't keep the blocks you're painting from becoming damp by 'waterproofing' the inside.
 
Sounds like you've already gone at it with a wire brush. As others have said whatever is left is probably on there good enough to leave. You certainly could try to sandblast or machine sand the surface down further.

Sounds like you have dealt with the water properly, with a drain system. That being said, I would not use ANY Thompson or Behr product below grade.

I will try to be brief here but 1/2 my family are contractors and I worked as a painter full time for a few years between high school and college. I have also reminded myself the hard way regarding Behr in my own home. The guy at home depot who recommended it might as well work at best buy.
Here is what I would do.
1) Prep the surface until nothing more can be removed without a machine or serious elbow grease.
2) broom/vacuum the surface off (it will have all sorts of concrete dust on it)
3)Apply 2 coats of either Drylok masonry waterproofer or Sherwin Williams Loxon block surfacer (I prefer Drylok)
3) Topcoat with 2 coats of high quality latex paint, Think Sherwin Williams or Benjamin Moore. Sherwin Williams' Duration line is one I like a lot.

If your drain system fails, the water will come in with entirely too much hydrostatic pressure for a product like Thompson's to deal with (I know, I know it's called "water seal") My route will be more expensive than yours, but as you know if you have been spending time down there with a wire brush, the work is not fun and thus something you don't want to do again. Spend the $60 per gallon and you will never have to do it again.
 
please make sure you have your sump pump on a power backup:
the floods in chicago area in the last 6-7 years did a lot of damage by shutting the power off first then dumping massive amounts of water. so no sump pump working.

also make sure your gutters are free of debris and that they dump the water really away from the house walls.
when it rains, go outside and check your flow and neighboor's too.
 
Ok

I went and bought a gallon of Drylock. I got about 1/3 done and I need to buy more paint. I really had to slop it on to cover everything.
I never knew how much work painting brick is. I had to use a large paint brush.

Making progress...
 
I have a large roll for brick however the Drylock is so thick I had better success just slopping it on with a large brush.

The wife said she would help after work today. With a helper I should be able to finish this evening.
 
don't worry, you'll be a hero for working so hard on the common dream house.
winter or not, make sure (for your health) you mind/dispense the fumes.
now would be a good time to ask for the favorite food/drink....
 
Yeah a large brush will work well. If using a roller, you will need one with a heavy 3/4" nap. Most rollers are made for finish work(3/8-1/2" nap) and those will not hold enough product or press deeply enough into your uneven surface. If going the roller route, a 3-5 foot roller extension will really help. It will allow you to use leverage and both arms to press into the surface.
 
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