Energy efficiency: Attic insulation upgrade issues

We all want our homes to be more energy efficient.  And, with attractive rebate incentives from local utility providers to improve attic insulation, there’s little reason to not jump on board.  In fact, priority #1 should be to air seal and insulate the attic.  Why?  Because hot air rises.  You want to keep it in the house.

A few issues I commonly run into when inspecting older homes that have recently installed attic insulation are concerning.  The most common is for insulation to be blown in around everything, including furnace flues.  Clearance requirements vary from manufacturer to manufacturer, but at least one (1) inch, free-and-clear, is required of all.  Insulation in contact with the chimney flue is a safety hazard and is all too commonly discovered.  The second issue I discover is blown-in insulation completely restricting the roof’s soffit vents.  By restricting attic ventilation, you run the risk of elevated moisture and humidity in the attic area.  This can lead to moisture and insect related issues, together with the real possibility of structural problems down the line.  The insulation contractor should install baffles (typically card board or styrofoam), designed to keep insulation away from the underlying soffit vents, and allow for free and unrestricted ventilation of the roof system.

So, yes, please have your attics insulated and brought up to prescriptive levels (typically R38).  But, ensure that your contractor does it right and keeps your home safe.  The simple installation of a sheet metal protective shroud around the chimney flues and soffit baffles will keep your home safe and properly functioning.  Plus, you’ll enjoy substantially reduced heating bills from the increased insulation!