DIYbanter - View Single Post

In article .com,
says...

I have those tiny dustlike black fungi that grow in the bathroom.
They're like very very fine black pepper but can become a significant
volume if left alone, and they're sometimes hard to rub or scrub off
the surface. Though I wipe them off, and sometimes it's hard, they grow
again. They also seem to be spreading to other rooms upstairs. I'd like
to kill them off.

I found this spray in a nearby store that's made especially for this
purpose. It's some antifungal spray. The only problem is that it seems
a little expensive at the recommended dose, ~4£ for each 2 square
meters. I have the bathroom and the whole upstairs floor to spray.

Does anyone know of a cheaper solution? Can bleach work? What about
vinegar?

A 1:10 bleach solution can kill them (1 part bleach, 10 parts water) but
there very well might be another source of the spores, like behind your
drywall. You must drill some holes in the drywall and look in there with
a flashlight (you might have to drill 4-5 inch holes to get a flashlight
and your eyeball in there.) If you have a behind-the-wall infestation
(i.e. that's where you can't clean and they can grow unmolested) you
have to take your drywall off, clean all surfaces with a bleach
solution, and put on NEW drywall.

Also check under your carpets, the pad could be holding moisture too. Do
a sniff test. Get on your hands and knees and try to find where the mold
smell is strongest, then pull up that area of carpet.

This is the procuedure most people use after a flood: Remove all drywall
(which holds water really well), remove any particle wood (like MDF
often used for sheeting/sheathing), and wash studs and weight-bearing
wood with bleach solution.

The last thing you have to do is find out why moisture is being trapped
behind your walls and feeding the fungi. Is there a moisture barrier
between the outside siding and sheeting? Not sure where code requires
the moisture barrier so consult a local builder.