Q: What are the three types of cellulose installations?
A:Spray applied: Also referred to as "damp spray" or "wet" cellulose. In this method of installation water is added at the tip of the hose in a very fine mist at high pressures. The cellulose is sprayed onto the exterior sheathing and builds up in the stud bay. Spray Insulation's policy is to fill the entire bay from back to front and from the bottom to the top with damp cellulose installed past its settled density. This method can only be used in new construction on exterior or interior flat walls.


All access cellulose sprayed beyond the studs is then brushed off with a scrubber making the cellulose even with the studs. All access cellulose is then vacuumed up, returned to the insulation machine and then is reused in the application process. By being able to reuse excess sprayed cellulose, there is zero waste in this process. This method is generally quicker in new construction and therefore cheaper. It requires a clean work site . The homeowner and builder can actually see that the insulation is completely filling the stud bay and has no chance to settle.

Dense pack: Also referred to as "dry" or "blown in" cellulose. We use a specifically engineered fabric called Insulweb that allows the air to escape as the cellulose gets denser and denser within the stud bay. The cellulose is installed well past its settled density and the entire bay is filled. The insulweb fabric is stapled up on all walls with pneumatic staplers. After installation, each bay is rolled with a roller to eliminate any bulging that could interfere with the sheetrock.

This method requires less cleanup time; however, more prep time is involved in stapling up the fabric making this method more labor extensive thus more expensive. The dense pack method allows for sheet rock to be applied immediately. Since you can see through the Insulted fabric you can ensure that the insulation will not settle.

In a cathedral slope the cellulose is dense packed into the bay either after sheetrock or with Insulted fabric and strapping to prevent bulging. Dense pack does not require either ventilation or a vapor barrier.

Loose fill: The method used to apply dry cellulose in a flat attic. A less expensive method to add cellulose insulation to an attic. Because the cellulose settles a few inches in the first few days, we recommend a settled depth of 16" or R60. This method requires venting and a vapor barrier.

Q: How long does it take for the spray applied cellulose to dry?
A: Depending on atmospheric conditions, you should wait at least 24 hours after installation before hanging sheetrock. Cellulose dries from the face back towards the sheathing and loses 1/2 its moisture in the first 24 hrs. If there are significant sources of moisture in the house such as an improperly vented heating system, or a new concrete slab, the drying time may increase. If the sheathing is below freezing, or if the walls are thicker than 6" then it will take considerably longer to dry out. Cellulose can actually help wet framing to dry and it dries in a controlled manner.