So the guy from Eco Foam concluded that I needed vent chutes around the attic perimeter and a layer of R-30 blown-in cellulose (about 9 inches) in both attic areas on top of the existing insulation. The vent chutes will allow for better cold air intake and overall circulation. This made sense to me considering my initial hypothesis that there was insulation obstructing the soffit vents. For some reason I couldn’t visualize what the baffle/vent chute would look like or how it would be installed so I did a quick scan of the web and found a couple things.
A little animated tutorial on insulating an attic. Mentions baffle installation a couple times…now I get it!
Itchy’s Do It Yourself Home Insulation provides a quick overview of installing baffles/vent chutes in both new construction and in an existing attic. He had a couple of great lines in the article that made me chuckle because it sounded like he was talking about me: “Installing the baffles [in an existing attic] is the same [as doing so in a new home] but it is a slower process and may require a certain amount of cussing to get the job done. But, that’s OK because nobody can hear you in the attic anyway.”
I can say with absolute certainty that based on the pitch of my roof and the amount of space it provides near the end of the eaves, there is not a chance that I’d get up in there and do this install on my own. About a year ago I installed some rolled insulation up there and that was miserable enough. Balancing on rafters and dripping sweat behind an air mask for an extended period of time didn’t instill loving memories of my attic.
Which leads me to another thing mentioned by the insulation guy. He explained how rolled fiberglass insulation isn’t as effective as blown cellulose. Basically, the R-value of fiberglass insulation decreases as the temperature decreases and because there are many openings and gaps in rolled insulation, air can blow through it, which negatively affects its ability to insulate. On the other hand, blown cellulose holds its R-value as the temperature drops, it doesn’t have the gaps like the rolled stuff because as it settles, it fills the voids, creating a more tightly sealed attic. AND it’s a recycled product AAAANND it’s cheaper than the rolled fiberglass.
So there you have it. $1378 will get me 9 inches of blown insulation and a bunch of vent chutes. Not sure how that compares to other parts of the U.S., but around here that’s not too bad.