Modern Insulation

Blow-In Insulation

Open Attics

A flexible hose is typically used to blow fiber into open attics.

Blow the specified amount of insulation evenly throughout the attic to achieve the correct R-value. The packaging will have the amount of insulation required to achieve the stated R-value.

TIP: If other insulation is already in place, Cellulose insulation can be blown over the top to increase the R-value and overall performance of the insulation. There should not be any reason to remove the previous insulation but be sure to check what you are going to be insulating before starting the process.

Safety & Comfort: There is often a dust produced when installing blown-in Cellulose insulation so wearing a mask and goggles is the safest and most comfortable way to do the installation.


Enclosed Wall

To blow Cellulose insulation into enclosed wall and cathedral framing cavities a 1 or 2 inch diameter reducer nozzle or “fill tube” is attached to the end of the regular hose.

A series of 2-inch holes are drilled horizontally through the drywall so the holes are centered in between each wall stud. The nozzle or fill tube is placed into each hole in turn to fill the wall cavity.

When using the nozzle, the Cellulose insulation is sprayed directly into the wall cavity until it is filled.

When using the fill tube, the tube is pushed into the hole and to within a foot of the far end of the enclosed cavity. As the Cellulose insulation is blown into the cavity it will pack down and continue to fill until it reaches the fill tube. As the dense Cellulose insulation gathers around the fill tube the blower will begin to stall. When this happens, the fill tube should be moved backwards until the blower picks up again. Once the wall cavity has been filled, move the fill tube to the next pre-drilled hole and wall cavity. The blown-in fiber compacts tightly around the plumbing and wiring providing an airtight insulation with an R-value approaching 4.0 per inch.

Although filling walls can be done from the inside of the home, normally wall cavities are filled from the outside. The same process as described above is used except that siding or roofing is removed to drill the holes for the fill tube.

Make sure you have high air pressure to ensure that the Cellulose insulation is firmly packed into the wall cavity. This is often called “dense-pack” Cellulose insulation.

Once the process is completed, the holes are plugged and the siding and roof covering is patched or reinstalled.

In new construction, walls must be enclosed with Insulweb scrim, fiber-reinforced plastic sheeting or drywall before cellulose can be blown into the framing. Choose whichever strategy makes the most sense for your situation.

If you have an older home that was insulated with inadequate levels of insulation, you are not out of luck.

Skilled cellulose professionals can snake fill tubes into a wall already filled with fiberglass batts. The installer fills the cavities with dense-pack cellulose in a way that crushes the existing insulation without balling up the batts, achieving a full uniform application of the new cellulose fiber. The goal on any application is to assure complete coverage that is installed at a density that will not settle over time.