How do you improve an old block foundation with no insulation or exterior moisture barrier?

Wilhelmina Lange
Updated: June 29, 2021

my house is 80+ years old; stucco clad; cinder block foundation which is 42" to 48" below grade; walls 30-32" above grade which slopes down and away from foundation/wall intersect.  Basement walls parged and painted with mold resistant paint; floor painted. Auto dehumidifier always on 24/7 year after year; fan oscillating at rear of basement; try to keep humidity around 55%.  Had energy assessment done - was recommended to instal blanket insulate floor to joist with 6 mil poly which was completed 2015. Last summer, hot humid weather here near north shore of Lake Erie, dehumidifier died. Found little 2-3" wide puddles along north wall, condensation inside poly at joists.  Moved wall shelving from east wall and found  very large puddling, some apparently had been there prior to this latest addition of moisture (along east wall).  Have had 7 fellas in to give me the news but all were differing opinions as to source and solution--1 fella just saying he 'just didn't know".  Along the east wall from corner over,I've cut away the black liner, pink batt and poly - all wet inside with small mold spots on what used to be a white wall. I've also removed the batts at the joists - which also are white and showing efflorescence.   What can I do to provide some warmth down there and keep moisture from invading my sweet little old home?? 

Responses (2)

Wilhelmina Lange
Wilhelmina Lange 3 years ago