Thread: Cellulose batt insulation

I haven't seen this used before, 3" cellulose batts with two layers over most of the attic. Anyone know the R-value of this? Note: this was the nicest 1983 attic I have ever seen, fully covered with radiant barrier, walk boards every where, not a speck of dust or one spider web, two shop light fluorescent fixtures made it look like an operating room with the reflective radiant barrier. (I could do this for a living)

Originally Posted by Vern Heiler

I haven't seen this used before, 3" cellulose batts with two layers over most of the attic. Anyone know the R-value of this? Note: this was the nicest 1983 attic I have ever seen, fully covered with radiant barrier, walk boards every where, not a speck of dust or one spider web, two shop light fluorescent fixtures made it look like an operating room with the reflective radiant barrier. (I could do this for a living)

The New 5 1/2 inch batts are rated R20

The ECOCELL 5.5" R20 batt is now available. Combining the ease of installation of a batt with the superior thermal and acoustical performance of cellulose insulation, ECOCELL batt insulation is the superior choice for insulation. Click here for more information.

Originally Posted by Billy Stephens

The New 5 1/2 inch batts are rated R20

The ECOCELL 5.5" R20 batt is now available. Combining the ease of installation of a batt with the superior thermal and acoustical performance of cellulose insulation, ECOCELL batt insulation is the superior choice for insulation. Click here for more information.

I found information on the 5.5" but this is 3". Should I just figure R of 3.6 per inch for total of R-22?

Originally Posted by Vern Heiler

I found information on the 5.5" but this is 3". Should I just figure R of 3.6 per inch for total of R-22?

That would be Close.

Originally Posted by Vern Heiler

I haven't seen this used before, 3" cellulose batts with two layers over most of the attic. Anyone know the R-value of this? Note: this was the nicest 1983 attic I have ever seen, fully covered with radiant barrier, walk boards every where, not a speck of dust or one spider web, two shop light fluorescent fixtures made it look like an operating room with the reflective radiant barrier. (I could do this for a living)

The really great part about this kind of batt is that it is friction fit. As you know the purpose is to stop air movement and create dead air. The batt itself only holds the air in place. Because it is a friction fit, it actually works better than fiberglass insulation when installed properly. How many times have you seen fiberglass that had gaps around framing members etc? No fiberglass protection needed, no itching.

The bad part about this kind of batt is its cost and the shipping of it about 30-40% abive fiberglass in most markets. It is not usually compressed and rolled and is very bulky to use, but that is what makes its installation more effective.

As to the thermal barrier, in your latitude it is not necessary under the rafters, only on top of the insulation. Make sure that the thermal barrier covers any wall that the air conditioned space is adjacent t0 and any area above and around air handlers. Also assure coverage of any gable ends facing east or west if the sun blazes hot ther in summer, you will however reduce winter heat gains by doing that so be careful the farther north you are. In Dallas where it is both hot and cold, we do a complete attic envelope of thermal barrier. I have seen attics drop from over 180 deg to ambient plus 3. THis seems to stop all hot and cold spots in the home as well as balance heat loads in areas that have been at issue due to poor engineering of AC systems.