Insulation R-value and quantity
Depth, bags, bundles or spray foam sets to reach a target R-value over an area.
Get this tool with its role plan
This is a premium tool. It comes with its role's plan: sign in, then add the role in Billing.
Comes with the carpenter plan: every tool for the role, from $10.20 a month at the launch price.
- Your own numbers, worked out as often as you like
- The full insulation certificate you can print or save to My work
- 4 cited sources, linked, with the checks to make
- Every other tool for the same role, in the same plan
- A plain-words read of your result (a fuller AI read with the Bifrost AI add-on)
Included in these role plans
Example result · fictional numbers
What you get: insulation certificate
Worked out by this tool from its default inputs. Its role plan lets you run your own numbers, print the sheet and save it.
Add 14.0 in of blown cellulose over 1,800 sq ft to reach R-49: 135 bags (25 lb)
- Installed depth
- 14.0 in
- Quantity
- 135 bags (25 lb)
- R per inch used
- 3.5
Insulation certificate (sign and post on site)
- Material
- Blown cellulose
- Where installed
- Attic floor
- Coverage area
- 1,800 sq ft
- Existing insulation
- None
- Settled thickness added
- 14.0 in at R-3.5 an inch
- R-value when done
- R-49
and 3 more lines
Also on the sheet
- Order and cost · 6 lines, starting with “To buy”
- Code and inspection checks · 5 lines, starting with “Code minimum”
The plain-words read of this example
R-49 in blown cellulose is 14.0 in deep at R-3.5 an inch. Over 1,800 sq ft that is 135 bags (25 lb). R-49 meets the R-49 you entered; ENERGY STAR lists the IECC-based targets by zone. Inspectors look for 6 depth markers and baffles at the eaves, and the signed certificate on site.
4 cited sources
- Recommended home insulation R-values (ENERGY STAR (U.S. EPA))
- Residential insulation inspection quick sheet (Seattle Department of Construction and Inspections)
- Blown-in insulation's measures and checks (Insulation Institute (NAIMA))
- 2021 IRC Chapter 11 insulation certificate, residential new construction (Yakima County Building and Fire Safety)
Plus 5 step-by-step checks, a print layout and a link that reopens it with your numbers.