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.
R value for attic ductwork.
If it was you don t have much recourse.
There are no r value requirements for ductwork installed in an indirectly conditioned space.
What i m talking about is a house with ducts in unconditioned space especially an unconditioned attic.
Why attic insulation r value matters for california homeowners at this point you may be wondering why this r value matters so much especially when it s for an attic that you probably go into once a year to fetch your christmas decorations.
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.
Recommended insulation levels for retrofitting existing wood framed buildings.
I called out the original hvac company and they took a look and said they saw no water.
R 6 duct insulation 6 305 btu hour 0 53 ton r 4 2 duct insulation 7 948 btu hour 0 66 ton the numbers are even higher for the additional heating load.
R value of 3 5 is required for buried ductwork and ducts installed in an unvented attic with roof insulation or in an unconditioned space including both ventilated and unventilated crawlspaces.
If the contractor added all new ductboard and your local code requires r 6 then you have some ground to stand on.
The attic ductwork is flex duct work.
Our r value cognitive dissonance.
R value of insulated ducts flexible ductwork running in open space like an attic will be insulated from about r6 to r10.
R value measures how well certain building insulation materials can resist heat.
Existing 3 4 inches of insulation.
Well your attic has a dramatic impact on the temperature throughout the rest of your home as well.
However this is a cost that pays for itself quickly so choose higher r values when given an option.
Here s how that 3 500 sf house would come out with those.
I m in georgia iecc climate zone 3 where our current state code requires r 13 in exterior walls r 18 in attic kneewalls r 19 in floors and r 30 in ceilings.
Know exactly how much you need with our project calculators.
When determining how much insulation you need don t guesstimate calculate.
The higher the r value the pricier the ducting.
For most applications a rating of r 6 or better will provide the best efficiency and long term cost effectiveness.
Add insulation to attic.
It was new when the ac was put in 7 years ago.
If we put ducts in unconditioned space they have to be insulated to either r 8 if they re in an unconditioned attic or r 6 in any other type of unconditioned space.
Purchasing the ducting and the insulation separately is often more cost effective and has a greater variety of options when it comes time to choose the r value of your insulation.