Too cheap to work

[JohnRoberts]

For a few decades I have wrestled with black mold inside my house. The high relative humidity and copious mold in local soil makes this too easy to get established. I had a leaking bathroom toilet water fitting that was left un-repaired for years. The bathroom humidity allowed mold to do what mold does. I won't bore you with the details but the long term solution that has been successful for years is to maintain indoor relative humidity at levels low enough to suppress mold survival and spread. Coincidentally when established mold is first deprived of moisture its first reaction is to blow out huge numbers of spores. This involved lots of cleaning indoor surfaces for years.

Running indoor dehumidifiers during winter months generates excess heat that is relatively easy to live with. During summer months extra indoor heat is obviously undesirable. My research suggests that indoor humidity can be as high as 60-70% RH and still suppress mold growth. I have a few cheap indoor temperature/humidity sensors that indicate "too high" humidity for levels >55% RH. I mentally understand that I should disregard the too high humidity warnings but they serve as a subliminal "nudge" for me to dehumidify more than is necessary.

I checked and modern versions of these same gadgets have raised the "too high" thresholds to 60%RH and 70%RH.... I just ordered a pair of 70%RH threshold devices. Hopefully this will save some energy and help save the planet.

JR

 

[cyrano]

Maybe it would be wise to figure out the exact species of black mold. Stachybotrys chartarum, Aspergillus niger, Claviceps spp or Fusarium spp. These are the four ones listed in my compendium as black mold. All of these produce a mycotoxin.

I kinda doubt it's Aspergillus, since that's more commonly found on fruit or nuts (pistache and peanut). It produces a deadly mycotoxin.

Stachybotrys chartarum is more likely, as it "eats" cellulose. It also produces a mycotoxin, but it's not as dangerous.

I don't know about the other two as it's an entire family. Claviceps purpurea, fi is the one that killed thousands in medieval times. Is it "mother of corn" in English? Or "ergot fungus"? Despite it's name, it's usually black. Fusarium is possible. Ever had toe nail fungus that's black? That would indicate a Fusarium species.

Over here, you can ask one of our universities to check it for you. Also, some water treatment companies do a free analysis, but they'll try to sell you something. And some, if not most fungal treatments are less than scientifically justified.

 

[JohnRoberts]

Maybe it would be wise to figure out the exact species of black mold. Stachybotrys chartarum, Aspergillus niger, Claviceps spp or Fusarium spp. These are the four ones listed in my compendium as black mold. All of these produce a mycotoxin.

I kinda doubt it's Aspergillus, since that's more commonly found on fruit or nuts (pistache and peanut). It produces a deadly mycotoxin.

Stachybotrys chartarum is more likely, as it "eats" cellulose. It also produces a mycotoxin, but it's not as dangerous.

I don't know about the other two as it's an entire family. Claviceps purpurea, fi is the one that killed thousands in medieval times. Is it "mother of corn" in English? Or "ergot fungus"? Despite it's name, it's usually black. Fusarium is possible. Ever had toe nail fungus that's black? That would indicate a Fusarium species.

Over here, you can ask one of our universities to check it for you. Also, some water treatment companies do a free analysis, but they'll try to sell you something. And some, if not most fungal treatments are less than scientifically justified.

Thanx but sorry if I wasn't clear... I do not currently have a mold problem. I did decades ago but by keeping my indoor humidity low (<60%RH) prevents the mold, whatever type it is, from reproducing. I kicked mold's a__ years ago.

My problem today is old humidity/temperature sensors that overstate the threat from humidity.


This sensor is probably 20 years old and suggests that humidity in the 50s is too wet.

The new ones (already on order) suggest that high 50s%RH is in the green comfort zone, so not too wet.

JR

 

[JohnRoberts]

This is before picture of back wall of my house. Rain dripping down from the roof, splashes up on the wall and supports mold growth. The after picture shows what my pressure washer did to black (?) mold on brick. Since these old pictures were taken, I added gutters to my roof that prevent feeding the mold so much moisture. The mold did not return without the water dripping from the roof.

JR