Mushrooms - Fungi - Growing on Building Surfaces

Detection and identification of mold or mushroom contamination in buildings

Mushrooms Growing Indoors

Brown fungus growing out of carpeting and floor trim combined with green mold on the exposed surface of drywall were conditions easily seen, and under which we assumed that the wall cavities were likely to be mold-contaminated in this area.

If you see mushrooms growing out of a building surface it's a safe bet that conditions have been quite wet and there is high probability of additional and substantial hidden mold growth and perhaps rot (and insect damage) in building cavities and in nearby wood structural members or subflooring.

Typically basidiomycetes or wood-rotting fungi grown on wet wood and can appear rather quickly even indoors in wet conditions

. These fungal fruiting bodies may appear in any of many colours, commonly brown, white, red, even blue or very dark, almost black.

Also see MUSHROOMS GROWING OUT OF BUILDING CEILINGS FLOORS or WALLS FAQs

More examples of mushrooms growing in or on buildings are

at WHITE MOLD PHOTOS

and
at MOLD on DIRT FLOORS - separate article, includes white mold on dirt in crawl spaces & basements

Examples of Mushrooms (mold) on Dirt Under Buildings

As we illustrate above and below, mushrooms of various shapes, sizes and colors are often found in damp or wet dirt crawlspaces under buildings

- discussed in detail

MOLD on DIRT FLOORS

Are these mushrooms growing on the wall in our garage?

I found your informative site after an hour or so of trying to find similar pictures to a mold/mushroom/fungus that I discovered in my garage yesterday.

I only noticed it after it dropped a clear liquid next to me. They seem to be growing out of the darker patches of moist paint/plaster.

Would that interest you to feature the photo? If you did, it might help me know what I could do about it. [Photo shown above]

Thanks and regards, On 2019-10-31 by Michael -

by (mod) - mold (or fungi) producing mushrooms growing on indoor surfaces

Michael

Thanks for the photo and question.

Other examples of mold (or fungi) producing mushrooms growing on indoor surfaces are at

YELLOW MOLD PHOTOS

and separately at

MOLD APPEARANCE on VARIOUS SURFACES we provide a large catalog of photos of what mold looks like growing on all sorts of building materials and surfaces.

What is the material and what are we looking at in your garage photo: this looks to me like a concrete or other masonry wall skim coated with a moisture-resistant paint.

Those blistered spots in the right side of the image look like paint being pushed off of the wall by moisture and probably by efflorescence - a mineral salt that forms as water moves through the wall and evaporates on the inner surface.

Some of the dark areas in the paint are likely to be one or more species of mold.

The "Mushroom" in your photo is simply confirmation that the area has been wet and that one of the mold species produced its fruiting body.

Am I right that this is a wall and that it's below ground level? If so your outside focus will be on getting water away from the building by addressing surface runoff and / or overflowing roof gutters.

Indoors, you can use any common cleaner to clean the surfaces and let them dry. But don't bother re-coating the wall before the water problem has been addressed.

Finally, knowing the genera/species of mold won't change the cleanup procedure; from the little we know here there's no justification for any further testing. Remove the mold and fix its cause.

Also see MUSHROOMS IN or NEAR BUILDINGS

Also see MOLD on PLASTER CEILINGS, WALLS where we'll include your photo. Thanks again: working together makes us smarter.

by Michael

Many thanks for the detailed response. It definitely proves your competence, as every one of your predictions of further details were correct; very astute.

I had to check with the owner's son about the wall material etc, but it is indeed a concrete wall, and he believes the paint was moisture resistant.

I have removed the fungus, brushed down the wall and knocked off the darker patches (wore a mask, just to be sure). I've dried the wall using heaters and heat guns, but the underlying problem as you said was moisture insidr the wall.

It is un the garage which as you rightly deducted is underground, as the garden comes up a level around the house. Having investigated, the garden patio where it meets the problem wall has perforations all the way along; each large enough to accommodate a fat ant to pass through.

Not sure how or why those holes have started, but it explains perfectly how the wall can get so wet. This is the thing that I'll need to fix.

Further, the garage used to be a chicken coup, 80 years ago.

And there was a metal chimney of sorts, of which the stove pipe is still in place in the unused outhouse the level above...turns out, with the current cold weather, water had been condensing on the inside of this pipe and running down and out in the garage, exactly where the 2 mushrooms were.

Once I get the patio/wall holes filled, I can tackle the metal pipe then re-dry the wall and paint it.

Many thanks for your invaluable help.

by (mod) - keep the water out from outside

Michael

Thanks for the compliments. Actually I'm just a 13 year old kid typing from my smartphone in Guanajuato, Mexico. It's dry here but we still see mold growth from time to time. (ok just kidding).

Comments:

It's always better to keep the water out from outside than to let it come in and then try to get rid of it; but beyond trying to seal the wall inside or out, at most homes the most-important step is to keep the roof drainage system working: clean gutters, unclogged downspouts, and downspouts take water 10' or more away from the building and dump it where it doesn't run back towards the foundation.

In-slope grade close to the foundation also sends un-wanted water in that direction.

Your detective work on noticing the abandoned metal chimney pipe as a source of moisture is great: I'd like to see some photos (one per comment is what works);

That too is best fixed from the roof-side (don't fall off the roof);

But the condensation also tells us there's a high indoor moisture level; In addition to stopping water entry as we've discussed, look for other moisture sources.