Allison bailes of decatur georgia is a speaker writer building science consultant and the author of the energy vanguard blog.
Attic ductwork r value.
This is why the r values are so different.
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.
R value is a measure of insulation s ability to resist heat traveling through it.
Recommended home insulation r values.
I check on the oc website and find that the 4 3 is the lowest r value they make.
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.
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.
My attic gets hot and so i was wondering how much cool air i was losing to the heat of the attic.
The attic ductwork is flex duct work.
If you measure air temp at evaporator coil and supply air temp from vents the air is picking up very.
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.
The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type.
Add the right kind of insulation.
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.
R value is a measure of insulation s ability to resist heat flow.
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.
Insulation level are specified by r value.
The higher the r value the better the thermal performance of the insulation.
These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.
Since the installation is in an unconditioned attic space i went up and looked at the duct install.
It was new when the ac was put in 7 years ago.
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.
So i notice the ductboard is oc s quietr with an r value of 4 3.
