Attic Ductwork R Value

It was new when the ac was put in 7 years ago.

Attic ductwork r value.

Since the installation is in an unconditioned attic space i went up and looked at the duct install. This is why the r values are so different. R value is a measure of insulation s ability to resist heat traveling through it. Insulation levels are specified by r value.

For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3. 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. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. 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.

If you measure air temp at evaporator coil and supply air temp from vents the air is picking up very. So i notice the ductboard is oc s quietr with an r value of 4 3. The higher the r value the better the thermal performance of the insulation. 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.

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. Allison bailes of decatur georgia is a speaker writer building science consultant and the author of the energy vanguard blog. The attic ductwork is flex duct work. 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.

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. Insulation level are specified by r value. I called out the original hvac company and they took a look and said they saw no water. The higher the r value the better the thermal performance of the insulation.

R value is a measure of insulation s ability to resist heat flow. 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. I check on the oc website and find that the 4 3 is the lowest r value they make. My attic gets hot and so i was wondering how much cool air i was losing to the heat of the attic.