The Cellulose Insulation Dry Pac System: A Guide for Contractors

If you’re a builder or contractor trying to hit high-performance targets without burning up the budget, it’s time to get familiar with the cellulose dry pac system.

‍

This method isn’t new, but it’s been quietly outperforming batt insulation for decades. And if you’re building tight, energy-efficient homes—or you’re tired of callbacks from homeowners complaining about drafts and noise—you’ll want this in your playbook.

‍

So What Is the Dry Pac System?

Short version: we staple up 6-mil poly, dense-pack cellulose behind it, and tape it off clean.
Long version: It’s a smarter way to insulate framed walls, locking in air sealing, soundproofing, and thermal performance all in one go.

‍

Here’s how the install looks on site:

‍

Step-by-Step for Contractors:

1. Hang the Poly
   Staple and stitch 6-mil poly over the stud bays after framing. That poly’s your containment.
2. Insert the Blowing Hose
   Cut a small slit in the poly. Feed the hose deep into the cavity. We’re not fluffing—this is dense-pack.
3. Dense-Pack Cellulose
   Use an insulation blower to pack each cavity solid. No voids. No settling later. Just clean, consistent fill.
4. Tape It Shut
   Once the cavity’s full, tape the slit. The poly stays intact and does its job as an air barrier.

‍

Why This Beats Batts (Every. Single. Time.)

‍

✅ Higher R-Value Per Inch
Dense-pack cellulose gives you better thermal performance than fiberglass batts, hands down.

✅ Built-in Air Sealing
Done right, this system slows air movement like a champ—no need for extra air-sealing steps inside the wall.

✅ Soundproofing, Too
Your clients won’t hear what’s happening in the next room or outside. Big win for quality of life.

✅ No Settling, No Gaps
Because it’s packed to the right density (3.5–4.0 lbs/cu ft), it won’t sag or settle over time.

✅ Eco-Friendly & Code-Compliant
Made from recycled paper and treated with borate—safe, sustainable, and passes every code requirement you’ll run into.

✅ Mold, Pest & Fire Resistant
The borate treatment keeps critters and mold out, and adds a layer of fire protection your inspectors will like.

‍

When to Use the Dry Pac System

If you’re working on:

✔️ New builds that need airtight performance
✔️ Additions that need to meet modern code
✔️ Passive house or energy-efficient designs

…this is your system.

‍

Why Nealon?

‍

We’ve been insulating shoreline homes and working with builders like you for 48 years. Our team knows the dry pac system inside and out—and we get in, get it done, and get out of your way so you can keep your build on schedule.

‍

👉 Ready to line up insulation that actually performs? Contact Nealon Insulation for a walkthrough or quote.

‍

P.s. Calculate how much R-Value your home needs