Snowy roofs across the Delaware Valley make a pretty winter scene, but melting roof snow can form dangerous ice dams. Preventative measures, like putting de-icing cables in the gutters or physically breaking the ice, only treats the symptoms. Attic insulation cures the problem. Snows melts on a cold day because your heated house is emitting warm air through the roof. Instead of battling ice dams all winter, learn how to prevent ice dams on a roof once and for all.
How to Prevent Ice Dams on a Roof
Select your insulation product for the attic. You need to achieve a 12-inch thick layer.
For fiberglass batts:
- Seal gaps in the ceiling around plumbing ventilation pipes and electrical wires with expanding foam spray.
- Measure length of channels between ceiling joists.
- Put on a dust mask to ensure you don’t inhale fiberglass fibers.
- Wear work gloves because the batts can cause skin irritation.
- Cut fiberglass batts to size with insulation knife.
- Lay the insulation between the joists with the paper vapor seal side on the bottom.
- Once the joists have been filled with batts, add another layer of batts across the floor joists.
For cellulose insulation:
- Spray the expanding foam around ceiling gaps to seal heat into the attic as much as possible.
- Make marks throughout attic structure 12 inches from ceiling. This creates a guide so that you know when insulation is deep enough.
- Choose a place outside to set up the blower below an attic window or vent.
- Put on a face mask and crumble loose insulation into the blower’s hopper.
- Run the hose up to the attic.
- Position yourself in a central location near the attic access door.
- Blow insulation into the edges first and gradually fill the whole space.