there is a gray flex that breaks down.
looks like someone split it open with a razor knife.
uv light causes it to break down, and just age.
I'd guess that in this area this gray flex was installed
25 years ago.
now flex has a silver reflective liner that reflects heat
life of flex as used in our state's calculations is 30years.
barring any rodent damage and correct install.
mine is a hot humid climate.
so life may vary in different climates.
can you give more detail?
best of luck.
The cure of the part should not be attempted without the cure of the whole. ~Plato
the neighbors (3 of them) have now found leaks in the attic flex duct. 16 inch main trunk lines. If they were anything like mine, they were installed loose. Mine had a 19 foot run and with the duct stretched out it was over 40 feet long. (mine got new metal ducts!!) The failures are in the inner duct. The wire appears to be ripping throught the clear inner plastic. This in turn billows up the outside gray jacket and cools the attic very nicely!!!!
Attic temps can be as high at 180 or above, as outside temps can be as high as 120. My thinking is that movement (repeated flexing), old age and heat have taken their toll!!!.
A poor installation should not reflect adversely on the product, in this case the flex duct. I agree that flex duct, when properly installed in the correct application, can last just as long as a galvanized system.
Everyone has a purpose in life..........even if it's to be a bad example.
Seek first to understand, before seeking to be understood.
Most flex duct is now rated for 200F maximum and has a mfg warranty against defects of 10 years. If your attic is at the temperature you state, you would be better off ventilating the space , replacing ductwork with steel and superinsulating the steel ductwork to reduce heat transmission.
Its not my attic that has issues. I tore that flex duct out last year and replaced it with sheetmetal!!!! I also added a ridge vent, eve vents and gable vents. I am well over the minimum code (by (by 2 times) for square inches of vent space per floor space . My ductwork is 16 inch screwed 8 times at each union, sealed (mastic), taped with aluminum tape (ul listed) and then pressed down with a plastic spreader. Then double wrapped with vapor barrier, r26 of insulation and finally reflective wrapped.
Mine does not leak, but the neighbors do!!!!!!!!! I was just curious as to the life span of flex duct.
We just had out 20 year old flexduct replaced as part of a system swapout. It looked to be in fine condition (a little dirty/dusty). It was the R6 mylar type. If I'd known it was going to look so good, I'd have probably kept it for another 20 years.
This is probably what your neighbors duct looks like. And what genduct is refering to. This stuff was used in the late 80's to the late 90's and should be replaced. It was typically found in track homes that also had polybutelene tubing and you probably have heard about that stuff.
Some Talk, Some Do
"keeping condensing pressures low and evaporator pressures high"
Comfort is my goal Blog Web Facebook