Does Your Home Need Drill & Fill Insulation?

Many of our clients ask us about how we install insulation in closed ceilings and walls. The process is called drill and fill. Drill and fill means that small holes are drilled into each bay of the wall then cellulose insulation is blown directly into the wall or ceiling to fill it using an insulation blowing machine. This technique ensures that every area of the wall or ceiling is filled with insulation – something that is not always possible with traditional batt insulation.


Oakland Wall Insulation Project

The quality of the work is great. Our house is warm and comfortable — much more so than the little apartment we just moved from. More than that, AHE staff was extremely friendly, knowledgeable, timely, and professional in all of our dealings. They helped educate us along the way about making our home more energy efficient, they made sure we were aware of any PG&E rebates that we’d qualify for, and they were always willing to answer our questions. We are very happy with the work we had them do, and we would gladly hire them again and recommend them to our friends.

Ashley in Oakland, CA


Drill & Fill Insulation Process:

  1. Depending on your home, drilling will either be from the inside or the outside of the house.
  2. One- to two-inch diameter holes are drilled into each bay.
  3. One installer operates the hose to fill each hole while a second installer operates the blowing machine.
  4. The two installers use cellulose insulation to fill each bay of a wall providing maximum insulation.
  5. After all holes and bays are filled with cellulose insulation, each hole is patched up.

This process can also be used to fill the space between floors, cutting down on the sound transfer.


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Drill & Fill Insulation For Older Homes

Homes built before 1979 typically have little or no wall insulation. In many homes batt insulation can only provide incomplete insulation which allows for more heat to escape. The answer to incomplete wall insulation is the drill and fill process.

Every spare spot on a wall can be filled with drill and fill insulation which is not always possible using just batt insulation. Filling every bay with insulation ensures maximum insulation benefits.This allows the highest possible R-value for wall insulation. R-value measures how effective insulation performs in various parts of the home. On older homes that might already have old wall insulation, drill and fill techniques can be used to re-insulate the walls and provide maximum R-value coverage.


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