Insulated flexible duct r8 silver jacket is used in standard heating and air conditioning hvac systems and some venting applications.
Using flexible duct for heating.
The duct has r8 insulation which contains 50 more insulation than the standard r4 2 product.
A good rule of thumb is to provide a duct support no less than every 4 feet and more frequently when using large diameter flexible duct 4c even when ducts are partially supported by framing members 4d.
Manufacturers then cover the tube in fiberglass insulation.
The master flow 6 in.
While those that sell flexible ductwork may have you believe otherwise it does not allow as much airflow as a similar sized metal duct.
Ideally ducts shouldn t sag more than inch per foot between supports and maximum sag should not exceed 2 inches 4e.
This additional insulation provides greater thermal efficiency to save energy.
Since it is so flexible it is also easy to obstruct the airflow even more.
Using this kind of ducting is best in tricky spaces where rigid ducts are not just possible to install.