Trapping Mildew Between Product Coatings

There is a scene in the classic original ‘The Karate Kid’ (1984) movie where Daniel (Ralph Macchio) is being coached by Mr. Miyagi (Pat Morita) through an exercise which Daniel believes is pointless at the time.

Daniel was shown by Mr. Miyagi a technique in which he should be stroking the brush when painting a house.

As the scene moves on, Daniel is visibly frustrated as he believes that the exercise is simply a way for Mr. Miyagi to cheaply get his house painted vs. having any real value in Daniel’s karate training.

These annoyances are soon squashed as Mr. Miyagi confidently walks Daniel through a demonstration of the value in the repetitive motions of the painting process and connects the dots as to how one has to do with the other.

While Daniel’s concerns may have been instantaneously quelled by Mr. Miyagi’s impressive show of what one had to do with the other (you have to see the movie to “get it”), my innards cringe every time I see the scene.

Though I do understand the value Mr. Miyagi was teaching, the painting genes embodied within my soul go absolutely bonkers as I watch Daniel paint directly over a mildew-covered house!

This is about as big a ‘NO NO!!’ of a scenario as one could put together.

Prior to any exterior paint job that we take on, we clean the outside of the building with what we call a ‘soft wash’ process.

This method is designed to clean the surface that it is being used on without damaging any of the substrate and without compromising whatever remaining integrity there is in the existing coating structure (i.e. – paint chips are not blown all over the neighborhood).

Properly cleaning these surfaces ensures that any mildew or mold is NOT trapped in between any paint or stain coatings.

In watching this referred to scene, as methodically as Daniel works to apply the paint in the manner which Mr. Miyagi guided him to do so, my insides turn inside out every time I watch it as brush stroke after brush stroke, Daniel applies the product directly over the mildew infested surface.

Even worse, from afar at least, it appears that the product being applied is an oil product over an oil product (which would make sense given the period of time).

Because mildew particularly feeds off the properties of oil-based paints and stains, Daniel is unknowingly creating a mildew sandwich time bomb (oil coating, mildew covered surface, a coating of oil on top)!

Once this type of scenario takes place, the mildew becomes trapped between product coatings.

Recently I visited with a client who had a mildew-covered, polyurethane-coated front porch ceiling.

With clear coatings, this type of situation is more visible than with more solid colors.

If the polyurethane ceiling is cleaned with a mildew cleaning agent and the mildew comes off, the client is golden.

If the mildew does not come off, then at that point the mildew is surely trapped in between coatings and the only way to solve the issue (outside of replacing the actual ceiling boards) is to strip off the coatings and start from scratch.

Not only is mildew unsightly, but with trapping mildew, mold, etc. in between coatings, even if mildew-resistant products and mildew inhibitors are used in subsequent coatings on top, it is only a matter of time before the mildew returns because mildew & mold beget mildew & mold.

Again, the only way to solve the situation at this point (without replacing the substrate itself) is to strip all the coatings and start from a clean surface.

Clearly, these are situations that can be avoided if the proper steps are taken as one is working through the project from the beginning.

It would not surprise me if within a year, the house that Daniel begrudgingly painted was covered in mildew and mold all over again.

As disheartening as this is for me to envision, perhaps Mr. Miyagi is well aware of what most likely will occur and has some type of advanced training technique up his sleeve for Daniel to embark in a year afterward, as he is now forced to strip the coatings off the house to rid it of its mildew.

Knowing Mr. Miyagi’s brilliance in the way he operated moving about things, it would not surprise me at all if this were the case.

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