6 Questions to Ask a Basement Waterproofing Contractor
Where is the home located, what is the exterior wall construction and type, how is the space heated?
It could be a whole host of different scenarios that would generate that result. It is nearly impossible to tell but I would say that most basement moisture problems are a result of bulk moisture intrusion or condensation issues.
Given the deep and hard winter this year, it could be a condensation issue that hadn't previously been shown.