Attic Ductwork R Value

Insulation levels are specified by r value.

Attic ductwork r value.

Add the right kind of insulation. Recently i had another hvac company come out and put in a new bathroom vent and they told me they believed the duct work was full of water. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. Insulation level are specified by r value.

R value is a measure of insulation s ability to resist heat traveling through it. The attic ductwork is flex duct work. So i notice the ductboard is oc s quietr with an r value of 4 3. 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.

The higher the r value the better the thermal performance of the insulation. When comparing r value between duct and attic insulation you have to consider the the air is moving through the duct and is already conditioned so it is picking up minimal heat from the attic air. It was new when the ac was put in 7 years ago. This is why the r values are so different.

I check on the oc website and find that the 4 3 is the lowest r value they make. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. My attic gets hot and so i was wondering how much cool air i was losing to the heat of the attic. The higher the r value the better the thermal performance of the insulation.

When insulating ducts understanding the meaning and impact of r values and insulation thicknesses is essential to getting the most efficient affordable outcome on your heating installation project the ratings provide a guide for homeowners that determines the effectiveness of the insulation making it easier to choose the right insulation for your home. 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. Allison bailes of decatur georgia is a speaker writer building science consultant and the author of the energy vanguard blog. And that means it s time to deal with duct insulation in a more meaningful way than just increasing the required r value to 8 for ducts in attics.

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. Since the installation is in an unconditioned attic space i went up and looked at the duct install. I called out the original hvac company and they took a look and said they saw no water. R value is a measure of insulation s ability to resist heat flow.