Attic Ductwork R Value

R 6 duct insulation 6 305 btu hour 0 53 ton r 4 2 duct insulation 7 948 btu hour 0 66 ton.

Attic ductwork r value.

7 948 btu hour 0 66 ton the numbers are even higher for the additional heating load. The effective r value of a buried duct installation depends on the size of the ducts the r value of the duct insulation and the depth of the loose fill insulation. Add insulation to attic. It will most likely be a fiberglass batt so multiply the thickness in inches by 3 2 to find out the r value or the r value might be visible on a product label.

There are no r value requirements for ductwork installed in other locations. Or you live in a state that doesn t require r 8 on ducts in attics. Not sure where you are at but here in florida the minimum r value for ducts installed in an attic or any unconditioned space is r 6. Return ducts ductwork that brings expended air back to the hvac system to be filtered reconditioned and redistributed require insulation with an r value of 3 5 for exterior ducts and ducts in a ventilated attic or unvented attic above an insulated ceiling.

R values represent the heat resistant properties of an insulating material. How often do you think you get the full labeled r value. Here s how that 3 500 sf house would come out with those. Ducting values are determined by two factors.

R value measures how well certain building insulation materials can resist heat. Recommended insulation levels for retrofitting existing wood framed buildings. The higher this value is the better you can expect the insulation to perform. If the insulation is a foam board or sprayed on foam use any visible label information or multiply the thickness in inches by 5 to estimate the r value.

If it was you don t have much recourse. It comes down to three options the first of which is to convert his attic into a conditioned space by installing 4 1 2 inches of polyiso insulation above the roof deck and then adding a new standing seam metal roof. Existing 3 4 inches of insulation. The duct insulation r values i mentioned above are what s on the product label.

I m looking at you mississippi and alabama r 6 and r 4 2 are common r values for ducts. Some other factors to consider. When determining how much insulation you need don t guesstimate calculate. Was your ductboard existing and you added a zoning system.

Look at your ductwork. Table 1 shows effective r values for 8 inch round ducts at three attic insulation levels and three duct insulation levels r 4 2 r 6 and r 8. The mass of the insulation consisting of both its density and thickness and the compression ratio at installation which determines the final compressed density and effectiveness of the insulation. The higher the r value the greater the insulation performance.