DIY Install of Dense-Packed Cellulose
Thought I’d share my recent experience dense packing cellulose in 2×6 stud bays.
As insulation contractors that do dense pack cellulose are few and far between in my area, I was pleased doing it myself with a rental machine was relatively simple and straight-forward.
I used a Krendl 425 blower, rented from my local independent building supply store for $45/day. Much of the information I used to figure out how to do it came from GBA articles, including comments on Martin Holliday’s blog post here:
First, I stapled and glued Insulweb across the stud bays. The glue was Elmer’s, thinned with a quart of water per gallon of glue and rolled over the stapled webbing. For a blowing wand, I used 4′ of 1 1/2″ schedule 40 PVC pipe, using exhaust pipe reducers to adapt it to the 2 1/5″ hose the blower came with. As recommended, I cut the end of PVC pipe at 45 degrees, making it easy to punch a hole through the web to blow the stud bay.
The Krendl 425 blower had plenty of power to dense pack the bays to 3.5-4 lb/cf. Based on bags used and total volume filled, my final density was about 3.6 lb/cf. Fill time per bay was about 4 1/2 minutes.
The biggest difficulty I encountered was static buildup from the plastic pipe and hose, that discharged periodically causing very powerful (and painful) shocks. Tying the hose to building ground at each hose clamp helped; grounding myself with a loop of bare copper wire around my wrist and a long length of lamp wire tied back to the building ground helped even more.
Attached are some pictures. Dense packing all the exterior walls in a 600 SF apartment took about two days, working over a weekend.
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