HomeCalcPro — 專案計算詳細報告
Tool: Insulation Calculator — 免費線上計算機 | HomeCalcPro | 列印時間:
Insulation Calculator — 免費線上計算機 | HomeCalcPro
Insulation Calculator精準試算，提供行業標準公式與即時測算結果。
Project & Material Dimensions
Estimated Material & Energy Output
Insulation R-Value & Bag Coverage Formula
Transparent mathematical methodology explained in plain English.
Thickness (Inches) = Target R-Value / (R per Inch [~3.5 Cellulose / ~2.5 Fiberglass]) | Bags = (Area / Coverage) × (R-Value / 38)Calculates necessary insulation depth to achieve Department of Energy (DOE) climate zone thermal resistance and determines bag purchase quantities.
Variables Explained:
- Attic Area (sq ft): Total horizontal attic floor footprint.
- Target R-Value: R-30 (Southern Zone), R-38 (Moderate Zone), R-49 (Northern Zone), R-60 (Cold Zone).
- Material Type: Blown-in cellulose, blown-in fiberglass, or fiberglass batts/rolls.
1,200 sq ft Attic Insulated to R-38 with Blown-In Cellulose
Calculating depth in inches, bags required, and estimated cost.
- Required Thickness: 38 / 3.5 = 10.9 Inches depth.
- Bags of Cellulose (approx 30 sq ft per bag at R-38): 1,200 / 30 = 40 Bags.
- Estimated Material Cost ($16.50/bag): 40 × $16.50 = $660.
常見問題解答 (FAQ): Insulation Calculator
Click any question below to expand quick answers, formulas, and expert tips.
What is the recommended attic insulation R-value for cold climates?
The US Department of Energy recommends R-49 to R-60 for uninsulated attics in northern cold climates (Zones 5–7), requiring approximately 14 to 17 inches of blown cellulose.
Can you blow new insulation directly over existing old insulation?
Yes, as long as the existing insulation is clean, dry, and free of mold or rodent infestation, you can add new blown-in insulation directly over it to boost total R-value.