Am I getting what I paid for?

When you decide how to insulate your home, you should give it a lot of thought. After all, this choice will affect you for as long as you own your house. Many people think that all insulations work the same, so they choose based on how much it costs to install. But there are many other things to think about. Long-term prices, comfort, and real-world performance are among the most important because they determine the value of your insulation year after year.

Aren’t all insulations the same?

No. Not even close. The R-value on insulation goods is a standard based on tests done in a lab. Also, each insulation is different because each building is different. The walls, ceilings, and floors are full of odd-shaped holes and barriers like plumbing, air ducts, and wiring. For insulation to work well, it must fill around these things without leaving any holes or spaces.

What can I do for my existing home?

It doesn’t matter if your house was built 100 years ago or just yesterday; you and your family can still enjoy the benefits of new insulation. Your attic and walls may have good insulation made of fiberglass. Covering the loose-fill fiberglass in your attic with more of the same stuff “fails to restore the lost R-value” 4 that happens naturally with low-density fiberglass. It makes sense that if you “cap” your existing low-density fiberglass insulation with high-density cellulose, you’ll not only add R-value, but you’ll also help reduce the free convection found in glass insulation and help restore the effective R-value that glass insulation promised but didn’t deliver during cold weather.

The sidewalls of many older houses had little or no insulation. We can add insulation to the sides of your home, which will make it use less energy and save you money. You will notice a change!

Different Types of Cellulose Insulation!

DENSE-PACK: In new construction, dense-pack cellulose is often blown behind an air-permeable polypropylene netting using a professional blowing machine. Achieving the proper density (at least 3½ lb. per cu. ft.) pushes the netting out beyond the face of the framing, so installers use an aluminum roller to flatten the material prior to hanging drywall. Properly installed, dense-pack cellulose is fully self-supporting, even if the netting is removed.

LOOSE-FILL: Loose-fill cellulose is typically seen in attic floors. Densely packed bales of cellulose are broken apart and fed into the cellulose blower’s hopper, where the material is agitated and blown onto the attic floor through a 2½-in.-dia. to 4-in.-dia semi-corrugated hose. To stop air leaks, installers.

DAMP-SPRAY: Damp spray adds water and sometimes adhesive to the cellulose fiber at the end of the blowing hose so the cellulose sticks to the framing. Cavities are overfilled and then the excess is removed with a rotating brush and vacuumed up for reuse. Although damp spray involves less prep work and installs faster than dense-pack, it’s tough to find installers who use this method, and it doesn’t work for roofs or ceilings as it doesn’t adhere well enough to support its own weight.


The R-value of cellulose is based mainly on its installed density, with denser installations generally delivering higher -values. Loose-fill cellulose has an R-value of R-3.7 to R-3.8 per in., while damp-spray and dense-pack assemblies are rated at R-3.6 per in. or higher depending on its installed density. The difference in appearance between a proper dense-pack installation and one with a lower R-value that is prone to settling or air leaks is tough to spot in existing construction, so you should ask for empty bag counts from the insulation contractor. Knowing the weight and number of bags blown and then doing some quick math to determine the density of the installed insulation will ensure you’re getting a quality job.


Cellulose insulation is so fire-resistant you can melt a penny with a propane torch while it sits on a handful of cellulose and the material will be only slightly charred. Its performance during a fire is backed up by its Class 1/Class A fire rating (it has a flame-spread rating of 15 or less and a smoke-developed index of 5 or less). These properties mean that cellulose will smolder, but it won’t burn without applying a high-temperature flame. Nu-Wool and other manufacturers offer over 50 UL-listed fire-rated assemblies, some providing up to three hours of fire resistance.


Cellulose is not technically an air barrier on its own, although at sufficient densities it can slow air movement enough to meet the envelope airtightness requirements of the 2012 IRC (3 ACH50 for most climate zones) without an additional air barrier. Cellulose’s air-sealing qualities are especially useful in retrofit work where existing walls are left intact and the cellulose is installed though holes made in the home’s exterior or interior. Cellulose is also less affected by wind-washing-a condition where air moving past the insulation reduces its insulating ability-than unprotected fiberglass batts or blown-in fiberglass. (See assembly details pp. 64.)