Blown-In Insulation

Blown-in is a method, not a menu — and the method is what determines whether the R-value on the bag ever reaches your attic floor. Loose fill is fed through a hopper, fluffed with air, and hosed across the deck through a long fill tube, building up an even blanket that drapes around joists, wiring runs, and the irregular framing a rigid batt can never sit flush against. That conformability is the whole reason loose fill exists: it has no seams, no friction-fit gaps, and no cut-to-fit waste. Prime Chimney Experts installs it the way the coverage chart demands — to the bag count AND the settled depth, not whichever runs out first.

Material choice changes the numbers, and we choose by the attic, not by what's on the truck. Cellulose delivers roughly R-3.7 per inch, packs denser, and resists air movement through the blanket better — but it's heavier and settles more, so we over-blow it to account for the drop. Loose-fill fiberglass runs about R-2.5 per inch, weighs less, settles barely at all, and won't wick water if the attic ever leaks — but at low density it lets more air drift through, so we blow it to the higher install depth its chart specifies. Hitting R-38 to R-49 means a real, different installed depth for each: a cellulose job and a fiberglass job to the same R-value are not the same height of fill, and a crew that ignores that under-delivers one of them.

Density and depth verification are the craft. We dial the machine for the target install density — under-fluffed cellulose blows light and settles into a thin, cold blanket; over-packed fiberglass wastes material and can lose loft. We over-blow above the final R-target so that when loose fill settles in its first weeks the SETTLED depth still meets spec, and we staple depth-marker rulers every few feet across the deck so the installed inches are a measurement you can read yourself, not a promise. We dam and baffle the eaves so the blower doesn't drift fill into the soffit vents and so wind-washing can't thin the perimeter blanket. How this differs from insulation-services: this page is the loose-fill blow itself — the one installation method — where that umbrella service decides whether blowing, batt, or spray is even the right answer and air-seals the envelope first.

One honest limit defines this method: loose fill is a conductive barrier, not an air barrier. Blown over an unsealed attic it simply filters the air still leaking through every top-plate gap and penetration, which is why we flag air-sealing as a prerequisite rather than pretend the blanket fixes leakage. We blow over existing fill when it's dry and intact (a top-off to depth), and we re-fluff or re-level settled, matted, or foot-traffic-crushed fill that's lost its rated loft. The premium is in the gauge readings, the over-blow math, and the documented settled depth — getting the method exactly right, every square foot.

Because PCE is national and standards-driven, the machine-density settings and over-blow allowance are tuned to the local climate zone and the chosen material's coverage chart in every market — a cellulose blow in a freeze-thaw northern attic and a fiberglass blow in a hot-climate southern one are each installed to their own correct settled depth. You're not trusting a crew to eyeball the hopper; you're getting the brand standard on the one thing this service is: loose fill, blown to a proven depth.

For a machine-blown, density-correct, depth-verified loose-fill install, call (682) 226-6257, anywhere PCE serves.