More questions about treating mold in crawlspace (cleaning, condo, cost)

[hmrd]

The owner of a condo near me wants to sell his unit, but can’t until mold in the building’s crawlspace is remediated.The mold looks very similar to that in the pictures posted by timd2010 in his thread “treating mold in crawlspace?”

https://www.city-data.com/forum/house...rawlspace.html

The association is thinking about having the crawlspace blasted with dry ice, which would kill and remove the mold, and the crawlspace would look great, but dry ice blasting is very expensive.

I’m planning to tell the association management about Concroblum fogging, which I learned about in timd2010’s thread, but I’m wondering whether the dead mold will still be visible after the fogging, and if so, what’s recommended to ensure the crawlspace can pass a home inspection and a buyer’s walk-through. Looks like the Concroblum company has cleaning products that could be used after fogging as well as a product to remove black mold (there’s a small area of this). If it takes two or more products and procedures, would that push the cost close to the dry ice blasting given that the association will be hiring professionals? Also, anything you can tell me about the likely price of each, especially in Raleigh, NC, will be appreciated. Just in case it influences your answer, the building is 160 ft long, 37 ft deep; the crawlspace’s height ranges from 4 ft to 6 ft.

I’m aware the high humidity needs to be remedied or mold will again appear, but in this post I’m just looking for answers that help me compare various methods of mold remediation (especially dry ice blasting and Concroblum fogging) for this specific situation.

One other question, can anyone tell me whether dry ice blasting or Concroblum fogging keeps mold from reappearing the longest? I know that mold can’t live and propagate in low humidity, so if the high humidity is remedied mold growth won’t be a problem. But just say, in a constant humidity of 75%, which would keep mold from appearing the longest? Anybody know or have some thoughts on this? I’ve read that either a microcode or biocide is sometimes applied after dry ice blasting. Does anyone know whether this extends the mold-free period?

[Jason Yost]

Fogging won't work in removing potential environmental triggers associated with the mold growth. And, dry ice blasting, while it removes the fungal structure from the building components, (1) has to be performed carefully so there is no cross contamination into the structure and (2) in conjunction with the removal of the causal factors (which led to the mold growth); otherwise, you'll just end up with another problem down the road and keep pouring money into this. Have you had an indoor environmentalist evaluate the structure and generate a protocol for remediation? This may give you and the complex options without remediation-bias.

[Jason Yost]

No one can guarantee you, with either of these methodologies, that mold won't be back in two or three days, given the 75% humidity that you describe. Furthermore, you may have other issues besides mold down there (with the humidity that high).