I live in an northern Ontario and question is in reference to insulation. The top 4 ft portion of an 8ft concrete basement wall has been wood framed and filled with fiberglass bat insulation. The lower portion of the concrete wall is bare.

There appears to be mold covering most of the insulation and signs of staining running down the walls from where the insulated portion is present.

Behind the insulation is what appears to be tar paper which is against the concrete wall. The moisture content is also quite high.

So what we have is open to air fiberglass insulation which is on top of tarpaper which is against the concrete wall. Most of the insulation has turned some form of dark discoloration.

Need more information
What is the floor .
Is the basement vented to the outside.
What is the outside temp.
What is the outside Humidity.
Is there and running water in Basement .
Do you have a sump pump and if so how often does it come on .
Do you have a humidifier in the basement and is it running .
What is the humidity of the basement .
Do you have a dehumidifier in the basement and is it running.
These are just a few question that need to be answered ,to try and help your concerns .
Do you have a clothes dry and is it vented to the outside .
Does any one hang damp clothes to dry in the basement.
Do you store fire wood in the basement .
Do you have a cistern in the basement and is there water in it.

Roy Cooke

Air movement can discolor fiberglass insulation. Discoloring or darkening is not, by itself, an exact indication of mold.