Silo // Types of Insulation

The Ultimate Guide to Blown-In Insulation Extrusion

The Very Good Home Company Engineering Team
March 1, 2026
4 Min Read

Simply throwing fresh white fiberglass over 30-year-old, compacted, rat-infested batting is a common contractor scam. To achieve true thermal performance and indoor air quality, the old material must be surgically extracted before the new "blown-in" blanket is laid down.

The "Dirty Sponge" Rule

Old insulation acts exactly like a giant sponge sitting above your ceiling. Over decades, it absorbs roof leaks, humidity, dead insects, rodent urine, and heavy dust. When you turn on your AC, the system pulls air through this dirty sponge. You would never put a clean sponge on top of a dirty one to wash your dishes. The same applies to your attic.

The Extraction Process:
  • 1 Industrial Vacuuming: We deploy huge gas-powered vacuums sitting in our trucks outside. 6-inch hoses pull everything out to the bare drywall without bringing a speck of dust into your living room.
  • 2 Sanitation & Sealing: We treat the bare deck for odors and physically seal all can lights and wire penetrations with expanding foam.
  • 3 The New Blanket: We blow in 13-16 inches of premium, snow-white, formaldehyde-free fiberglass back over the sealed attic floor, ensuring zero gaps.

Stop Reading. Start Fixing.

Your house won't fix its own thermal leaks. Schedule a complimentary diagnostic sweep and see exactly where your HVAC is bleeding cash.

Deploy Thermal Audit