Breathable Walls Prevent Moisture Failure — FarmPal
Natural material walls must breathe vapor-open assemblies allow moisture to pass through without trapping it. Never use vapor barriers (plastic sheeting) on earth, cob, straw bale, or hempcrete walls. Use lime plaster (not cement) for exterior coats lime is vapor-permeable while cement traps moisture, causing spalling and mold. The rule: walls should dry faster than they get wet. Monitor wall moisture with a pin-type moisture meter readings above 20% signal problems.
Natural material walls must breathe vapor-open assemblies allow moisture to pass through without trapping it. Never use vapor barriers (plastic sheeting) on earth, cob, straw bale, or hempcrete walls. Use lime plaster (not cement) for exterior coats lime is vapor-permeable while cement traps moisture, causing spalling and mold. The rule: walls should dry faster than they get wet. Monitor wall moisture with a pin-type moisture meter readings above 20% signal problems.