Free Calculator
Blown-In Insulation Calculator (Bags Needed)
Find how many bags of blown-in fiberglass your Florida attic needs to reach R-38 — plus depth, coverage, and installed cost.
Total conditioned square footage (from your listing or tax record).
Blown-in fiberglass needed · 2,000 sq ft home
~26 bags
To bring your ~2,100 sq ft attic to R-38 you'd add about 5.4″ of new blown-in fiberglass.
Estimates are for planning only and based on typical Central Florida homes and 2026 pricing for blown-in fiberglass. Your exact price depends on attic access, existing insulation condition, and whether removal is needed — confirmed free during your inspection.
Blown-in fiberglass is sold and installed by the bag, with each bag covering a set area at a given depth. This calculator estimates how many bags your attic needs to reach R-38 based on its footprint and how much insulation is already there.
It uses the same footprint and depth model Florida Attics uses to price real jobs, so the bag count lines up with an actual installation.
What goes into this estimate
Attic footprint. Estimated from your living area and stories — the area to be covered.
Depth to add. How many inches of new fiberglass to reach R-38 from your current level.
Bags needed. Footprint and depth converted to bags at typical R-38 coverage (~30 sq ft/bag at full depth).
Frequently asked questions
How many bags of blown-in insulation do I need?
It depends on attic square footage and the depth you're adding. A typical 2,000 sq ft Florida home needs roughly 40–70 bags to reach R-38 — enter your home above for an estimate.
How much area does one bag of blown-in insulation cover?
Roughly 25–40 square feet at a full R-38 depth, depending on the specific product; more at shallower depths. The exact coverage-per-bag is printed on every bag's chart.
Is blown-in fiberglass good for Florida attics?
Yes — it's the best value for most Florida attics: affordable, non-combustible, doesn't absorb water, and reaches R-38 easily.
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