Black substance on insulated panels

This black substance was observed on insulated ceiling panels in a cold store underneath the front patio. The patio has minor cracking so water might be getting down here. My guess is that they sealed the top of theses panels with some black sealant that leaked down in the seams. What do you think it is?

Microbial type growth would be my “guess”. Mold or mildew, but photos are inconclusive.

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Looks like mould from here.

From here it looks like an organic substance consistent with mold.

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Looks like mold here— or in my report, microbial growth.

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A below grade cold room I take it. Please, correct me if I am wrong.

My 2 cents: Appears a bitumen mastic was mistakenly used to seal gaps between insulation and to stick the Styrofoam panels to walls and ceilings, instead of using a proper Styrofoam insulation construction adhesive suited for the substrate, concrete.

The mastic became a mixture of bitumen and water, weakening the viscosity of the mastic. Seeing bitumen is a petroleum product, and doesn’t mix with water, an emulsion took place and the mastic mixture emulsified into fine droplets separating from one another leaving the circular patterns you see on the ceiling.

Mold, I do not think so.

Sure looks like mold-like substance and that is how I would report it. You may be correct, but only testing will confirm.

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Morning, Lon.
To me, not as a pattern.
As well, as a product, spray foam insulation, does not attract mold. And unlike wood or metal, spray foam does not rot, rust or deteriorate. This means that an area properly sprayed with foam insulation will never become a food source or a hospitable environment for a mold colony.

Mold needs 3 things, water, food and oxygen. The environment would include proper temps.

I agree with you, foam is not typically a food source. However, we often see mold growing on many things such as synthetic carpet or materials, painted surfaces, plastic etc.

In this case, dirty water can transport nutrients for mold to thrive. Other sources of nutrients can be as simple as cooking residue, dead skins cells etc.

So, as stated by others as well; it is visually consistent with mold, the environment for mold is possible and would require testing.

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