High humidity?

[jordanphulet]

At what RH values should I be worried about damage to my home. I got a meter yesterday, it measured 65% this morning.

 

[hawkinsrgk]

I had black mold in the basement when mine got to 70 percent. I have since bought a dehumidifier and run it at 55 percent

 

[pecan2phat]

I sectioned off part of my basement and enclosed a fish room about 8.5 years ago. I have multiple tanks and a basement sump setup in there. My humidity averages 70% most of the time. I utilize an inline fan connected to two ceiling vents with a humidistat controller and also employ a vented portable AC/Dehumidifier/Heater when needed.
With all this proactive prep, I still developed black mold on exterior sided walls around the 3rd or 4th year. I now need to wipe down all these surfaces with bleach twice a year just to keep it in check and certainly not eliminating it.