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Vapour Open Paint – Pealing

charles_biden | Posted in General Questions on

Hi everyone;

So, I am currently painting my CMU house. I have some water-related problems that have ruined my paint job.

First, I have significant raising damp. Secondly, I have poor roof overhangs and therefore, my walls are seeing a lot of rainwater. My actual paint is not vompletly vapour open. 

In this phase, I only have the budget to deal with the walls. I have been recently advised by the contractor that I must use a vapour open paint in order to allow that moisture to escape. However, I am afraid that also leads to pealing, essentially in the raising damp areas.

He also suggested that I could choose an EIFS without the insulation. But if I have rain or soil water behind this finishing layer won’t it start to peel and fall apart?

Any thoughts on the best solutions?

Thanks

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Replies

  1. user-2310254 | | #1

    Charles,

    EIFS without the foam (stucco) doesn't make much sense to me (as a non-expert). Most of the work in installing the system is the stucco application. If you decide to go in that direction, I would get the foam.

    I'm assuming the home is existing, and you painted over existing coats of paint. Is that correct?

  2. PLIERS | | #2

    Did you paint over an old layer of paint? You need to remove any peeling or cracking paint off first to get a good adhesion. Years ago I had peeling paint on a concrete banister, I scraped off all the loose paint and used an anti peeling paint as a primer, I think it’s made by killz before painting over it. Held up for a long time, paint still not peeling, it’s outside the newer paints are less toxic but you have to go over every few years.

  3. Expert Member
    PETER G ENGLE PE | | #3

    Peeling paint is the least of your problems. The photos of the patio show pretty clear signs of masonry corrosion. This occurs for lots of reasons - old true-"cinder" block where the coal ash used as aggregate reacts badly with the cement over time is the biggest. Freeze/thaw makes it worse. Anyhow, those patio foundation blocks are becoming rotten and a pretty big rebuild is on the way.

    Fortunately, the house walls don't look so bad, but it is important that you do what you can to keep them dry. There's not much you can do about the rising damp. There are some chemical treatments that soak into the block, but I've heard mostly mixed results with them. The EIFS idea is not a bad one, but I would also recommend adding an inch or two of foam, as with standard EIFS. The acrylic stucco coatings used with EIFS can be good coatings when directly applied to block, but if the block is significantly wet, they will still blister and peel. If you include the foam layer, the block will still get damp from rising damp, but it will be warmer in winter and see far less freeze/thaw. And, the moisture will be better dissipated within the foam layer and less likely to concentrate in one place. The acrylic coatings are relatively vapor-open and can tolerate a certain amount of moisture and vapor flow through the materials. Note that the EIF systems must be terminated a few inches above grade. You can use the coating direct-applied to the CMU below that, but the coatings will take a beating from the weather and will require periodic scraping and recoating.

  4. ursalacim | | #4

    The best way you already missed, if you haven't had any experience with painting, you should approach professional painters to avoid the problems that you are having now. As I know, professional painters check the weather conditions and other factors to choose the proper painting. Also, they look at the medium temperature in the area, and only after that do they choose the proper painting. In your case, it is not too late to approach a professional painter's service. You can write in google painters Ballarat, and I'm sure you will find a good service in your area. https://perfectpaintersinballarat.com.au/

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