Insulation Cost Calculator

This prices the insulation job that a quantity calculator leaves at bags and batts. Give the area, the R-value you are aiming at and a price per board foot, per bag or per square foot, and it returns the thickness needed, the quantity, the material and labour cost and the cost per R per square foot. A second tab puts all nine materials at the same R-value side by side, with the depth each one needs and whether it fits the cavity you have. A third estimates the annual fuel saving from the extra R and the simple payback. Every price on the page is an editable field with a placeholder in it rather than a quote.

Calculator Type
Measurements In
This moves the whole form and the answer with it: the area, the resistance you are aiming at, the bag coverage, the labour rate, the thickness that comes back and the quantity. Prices are in dollars either way.
How the Price Is Quoted

Area, the R-value you are aiming at and a price. Gives the thickness, the quantity and what it comes to.

An R-value, or RSI if you switched above. Left blank this is R-49, or RSI 8.63 in metric.
An R-value, or RSI if you switched above. Zero if there is nothing there.
Square feet, or square metres if you switched above. Only needed when the price is per bag. It is on the bag chart against the depth you are going to.
Read in whichever area unit you picked above, so a square foot rate on square feet and a square metre rate on square metres. $0.45 per square foot is $4.84 per square metre.
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Measurements In
This moves the area, the resistance you are adding, the depth available, the nine prices and the whole table. Left on square feet the nine prices are per board foot; on square metres they are per cubic metre, a cubic metre being 423.78 board feet.

The comparison the thickness hides: a material at twice the R per inch needs half the depth but rarely costs half as much. Same area, same target R, your own prices.

An R-value, or RSI if you switched above. R-30 is RSI 5.28.
A 2x4 bay is about 3.5 in and a 2x6 bay about 5.5 in. Leave it blank for an open attic.
Left blank this is $0.05 per board foot, which is $21.19 per cubic metre.
Left blank this is $0.04 per board foot, which is $16.95 per cubic metre.
Left blank this is $0.12 per board foot, which is $50.85 per cubic metre.
Left blank this is $0.23 per board foot, which is $97.47 per cubic metre.
Left blank this is $0.50 per board foot, which is $211.89 per cubic metre, and starts as an installed price.
Left blank this is $1.20 per board foot, which is $508.53 per cubic metre, and starts as an installed price.
Left blank this is $0.55 per board foot, which is $233.08 per cubic metre.
Left blank this is $0.70 per board foot, which is $296.64 per cubic metre.
Left blank this is $0.62 per board foot, which is $262.74 per cubic metre.
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Area Measured In

What the extra R is worth per year in fuel, and how long the job takes to pay for itself. A degree-day estimate, conduction only.

An uninsulated but finished ceiling is roughly R-2 to R-3 from the drywall and the air films, not zero.
Roughly 2,500 on the Gulf Coast, 4,000 in Virginia, 6,500 in Chicago, 9,000 in Minneapolis. Your weather service publishes the local figure.
A condensing furnace is 90 to 97, an older one 70 to 80, electric resistance 100. For a heat pump enter the seasonal COP times 100, so a COP of 3 is 300.
Fill this in to get a simple payback.
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