Cover wall and drop ceiling cavities to prevent filling these areas with insulation. If knob and tube wiring is present, a licensed electrician should certify that insulation can be safely installed. Once the above steps have been completed, insulate all attic areas to the maximum settled density possible, usually R-30. A floored attic may limit the amount of insulation that can be installed. To maximize your energy savings, insulate all attic entryways such as hatchway openings, kneewall access doors, and walk-up stairways.
Attic ventilation reduces summer heat build-up and prevents winter moisture condensation.
Both problems can be costly and damaging, and both can be virtually eliminated by effective attic ventilation. Differences in home construction and design are a major factor in choosing the right type or combination of vents. Vent location, style, and size are all factors to consider when insulating your attic. A qualified contractor will know the formula by which to determine how much ventilation you will require. Important factors in the formula include the existence of vapor retarders, location of existing ventilation in relation to the eaves, and square footage of the attic.