Insulation Efficiency and Condensation
Is there a condensation risk to a house if the insulation over the exterior walls and outside edge of living space on main floor is removed or reduced to allow space for an attic ventilation system? If not, great. If yes, what would be a recommended fix?
• House built in 1939
• Roof joists end above the exterior walls
• There are No soffits and there was No ventilation in the attic
• Roof is very steep
• Finished, conditioned room is in the attic
• Blown insulation encapsulated inside cardboard-like covering along entire roof line and knee walls
• Each knee wall has a door (covered with foam board) to allow access to open space behind.
• Had wood sheathing pulled up to install 16” wide baffles (2” air flow), Edge vents full length of house (front + back) for air intake and Ridge vent across peak of roof for air exhaust.
• Baffles extend from the top of the roof line and end 1-1/2 feet above base of each rafter bay.
• All insulation removed from above exterior wall (1 foot) and some additional insulation removed in base of each rafter bay to insert the DCI Smartvents. There is a 1” gap between where underside of edgevent ends and baffles start upward. Contractor indicated gap isn’t an issue and that insulation will not enter baffle.
Two pictures attached.
My question is, with the removal of insulation at the base of the roof (over the exterior walls and some of the main floor living space) is there a risk of condensation behind the plaster walls or in the outside perimeter space between the attic and lower living area?
Would appreciate thoughts from those in the know on house construction and insulation. Am I worrying over nothing or is this an issue I need to have fixed to prevent issues down the road? Your thoughts would be very much appreciated.
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