When these ducts are exposed to exterior air the plastic jacket never gets cold enough to permit condensation because the hot attic air keeps the plastic jacket warm.
Flex duct in attic.
It also makes maintenance and or modification easier.
The official recommendation from the adc is that flex ducts should sag no more than 1 2 per foot of length between supports.
The attic is a hot dirty nasty place.
Just blow the attic to r 38 and over the top of ducts if needed.
People can not carry ladders up into a attic and them place them onto 1 1 2 wide boards so they can climb over ducts.
The lower the cooler it is.
It s done this way because it s easier and cheaper to run a flex duct through a wide open space than to fit it through and around floor and wall framing.
The master flow 4 in.
Insulated flexible duct r6 silver jacket is used in standard heating and air conditioning hvac systems and some venting applications.
Ducts are to be part of what is inside the house not part of.
The costliest are sheet metal ducts running in enclosed walls and ceilings.
Around that is the outside cover of the duct itself.
The higher in the attic the hotter it is.
It was new when the ac was put in 7 years ago.
Ducts up high get tore up.
They just tear through them smash them climb on.
The supports need to be at the manufacturer s recommended spacing but no longer than 4 maximum.
The duct has r6 insulation which contains 33 more insulation than the standard r4 2 product.
How to hang flex duct in an attic 1.
Blown in insulation is cheap.
The straps that hold up the flex duct need to be no less than 1 5 wide.
Flex ducts consist of a spring that is wrapped with a very fragile layer of plastic.
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.
Not part of what is in the attic.
If ducts are to be installed in a vented uninsulated attic or crawl space hang the ducts with supporting straps or saddles of sufficient width and frequency to adequately support the ducts so that the ducts do not sag and are not pinched or compressed in a manner that would cause damage to the ducts the duct insulation or the duct air barrier covering.
Ductwork running along an open ceiling in the basement of a one story home is also more affordable to replace.
Secure the webbing to the joist by hammering a 2 inch roofing nail through the webbing and into the side of the joist.
Most attic ducts are insulated flex ducts that is flex ducts with r 6 or r 8 fiberglass insulation along with an exterior polyethylene jacket.
Type of ductwork system the least expensive duct system is a radial system of flexible ducts in an attic running to ceiling grates.
This additional insulation provides greater thermal efficiency to save energy.
A layer of insulation covers this thin layer of plastic and blocks the heat from getting in or out of the duct.
