Attic Heating Ducts

The 1 800 square foot brick ranch in climate zone 4 dates from the 1960s but the previous owner installed both a furnace and ductwork in the attic just four years ago.

Attic heating ducts.

If you notice a musty or moldy smell that goes away when you are not using your air conditioning or heating if they share ducts that can narrow the cause down to mold in your hvac system. Install ductwork so that it is in direct contact with i e laying on the ceiling and or truss lower cords. There will be less duct leakage. However an attic in pensacola florida is likely to have a humidity level closer to 100 and the risk of condensation on ductwork would then go up quite a bit.

1 10 5 25 per foot insulated flexible duct 4 to 16 diameters used as branches or in radial duct attic systems 2 30 13 00 per foot round and oval sheet metal duct 3 to 8 diameters typically used for trunks in small homes and. Ted has more than a few cobwebs in his attic. Use metal flex or fiber board ducts that are insulated to. In the 70 s and 80 s in slab hvac ductwork was commonplace and took advantage of the relatively stable temperature of the slab at or near the ground.

The air ducts for a central hvac systems are typically located above a home in the attic or upper crawl space or underneath a home in the space between the foundation and the floor so you don t see them unless you have cause to replace them. An unusual or musty odor is often the first sign of mold in air ducts or in air vents. Use the type of. Flexible duct is a plastic tube that is reinforced with wire and then insulated on the outside.

The next most typical type of duct systems is made of flexible duct. The unconditioned space also houses his hvac system. Here s why that is a good thing. Attic hvac systems also require shorter ducts.

With newer foundation systems involving embedded rebar or tension cables making in slab hvac ductwork nearly impossible there s little other option but to move it to the attic. Here are the itemized costs for the most common types of ductwork and supplies needed to complete installation. Don t use standard cloth duct tape on hvac ductwork since the adhesive won t hold up to extreme temperatures. The really bad news is that with old metal duct systems the only option is replacement of the ducts to stop the rain in the attic.

For an added layer of protection you can apply duct mastic to the tape and duct. When insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value. In many cases you ll smell it before you can see it. Because the average humidity level is 10 20 in phoenix.

Flex ducts themselves do not sweat however if the. When hvac ducts are installed in a vented attic in a dry climate bury the ducts in attic insulation to protect them from temperature extremes in the unconditioned attic space. All ducts are at risk for this type of leakage. Duct leakage causes a lot of problems including less.