Such a legend... When I first started in the trade I credit a lot of what I know to this guy, and to this day he's still putting out great content. Thank you Brian!
This should be mandatory viewing for all HVAC people. I’m about to go repair a bunch of trunk line leaks by using alcohol and tape and mastic and this video just added days to my job because I can’t unsee all the bends and touch points of duct on trusses. I will happily be resolving all these issues knowing that I did them right, once, and never have to deal with them again. Thank you.
Thank you for this great video! When I added straps to my ducts, I put a sleeve underneath the ducts made from cardboard to avoid compression and kinks. Also for each boot, I added some Malco FDS1- Flexible Duct Support to keep a nice curve from the floor. They can be used as well if you have some ducts leaving the plenum at an angle. Also, if the attic has already a radiant barrier, it doesn't matter if your ducts are black or silver, something to consider. While ducts are part of the system, sealing and insulating the plenum is something to do to help against air leaks and temperature swing.
Appreciate the lesson. I'm just a homeowner, but trying to get educated on how to improve my home's energy efficiency, to lower my painfully increasing electric and gas bills. Seems my situation is different because my A/C and ductwork in all in the basement and it's a conditioned space, therefore leaks and condensation probably aren't as much of a factor as they are as when it's all up in a hot humid unconditioned attic. Still, I can use these techniques for optimizing the system.
This channel is great. I'm trying to improve my airflow and reduce my air leakage from the homeowner-done hvac job and I have learned a ton. Unfortunately, most of my flex duct is resting on the joists in my attic and I'm not sure there is enough slack to lift it off the joists, but I'm going to try. If that doesn't work, I may be replacing all the ducting as time and money allows.
Very informative as always. Good tips about silver/black duct and best ways to make connections. Really wish there was more about different types than just flex but still good video. I know you have to keep to your market.
If you look closely at the foil you will see good flex has reinforced string every 1/4" instead of every 1/2" that some manufacturers use. Reduces rips when moving it around during installation.
Why would anyone purposely install a unit into a very hot attic (140/150 F) and expect it to be efficient? System spec’s are most likely being violated! Please explain without sarcasm. Thanks!
Retrofits and remodels. Here in the DC/Baltimore area, brick rowhouses have this all the time, especially high velocity units. It opens the floor/wall space that a closet air handler/furnace takes up. Flippers are mostly about profits more than efficiency. In detached new builds around here with bigger, more open truss attics, that system is usually just for the upper floor zone so any efficiency comes from it not having to condition the entire house, only up there.
I have a question, on round metal duct work return air systems, specifically adjacent pipe connection, does the return air duct have to follow IRC Duct Lap rule. I understand the Supply air needs to follow this principle, but does the return air branch duct connections need to follow this rule as well?
I bought a house in 2022. The hvac hadn't been updated since house was built in 1996. The ducts had stinky mold so we decided to have new hvac and all ductwork replaced. Hvac system and box shaped sheet metal duct (with insulation inside) trunklines were in crawlspace with flex ducts running off metal trunk line. We had a small company replace all ducts and complete system. I was kinda surprised after install when I noticed they didn't use any sheetmetal ducts at all... only flex ducts for the entire system... Is that normal? Anything wrong with using all flex ducts to replace old metal trunk line?
Black flex duct in the attic is "less efficient" in the cooling season, but black flex duct in the attic is "more efficient" in the heating season. Correct? What ACCA approved J-manual software addresses the flex duct covering color, which then includes its heat gains or losses?
Northeast, land of crawlspace and damp basements. Literally rains off the insulation blanket. Ruins F/G wrap. I love the foil bubble wrap. Now a growing business is crawlspace incapsulation, sealed with dehumidifiers. You can smell the difference in new homes with a incapsulation system installed over homes just a few years old without them sealed and conditioned.
How do I know the maximum airflow, CFM, that can be handled by some 6” flex duct I have in my attic, if I put in a booster fan to be able to increase aire flow at certain times? The duct says 4000 FPM maximum, it’s 6” duct and I’ve got about 15’ of duct run before the booster fan and then 15’ after The dan to the vent? Thanks in advance for any help on this.
Pretty sure the black stuff for trailers are thicker material that can lay against water and the ground. Silver stuff is more easily torn through by critters and tears more easily when laying against the ground.
All due respect if you use a panduit gun on the inner and outer it’s not leaking at all….I realize the codes vary in certain markets but if you use a gun properly there’s no way
Flex is all garbage, and is even illegal in some areas. Better not put it under a skylight,because it will blow apart from degrading in the sun. I. Have had numerous calls where rats chewed thru the stuff and peed and pooped inside it. Metal duct is the only way to go. But of course, sadly, standards have changed. Flex duct was designed to be used for short connections to the diffusers. A properly used set of panduit straps is superior, but you have to use the tool to tension them properly. They won’t fall off if you use a collar with a bead. Just examine the labor difference. Two straps, liner and outer jacket, then a wrap of insulation over the top. All that fussing over mastic, tape, etc, etc to seal an inferior duct product just doesn’t make sense. I’m not trashing the instructor here, I think he is great. I am trashing flex duct though, I’ll have to admit.
Hey have you ever tested wrapping one pass of mastic tape around the collar which has a little “give” and will act as a seal - and then use the panduit strap which should compress down into the mastic tape. I think I would rather do that then play with mastic inside the collar
Metal ducts are the only way to go, which I found out the hard. First I had flexible ducts installed and they off gassed so bad it made my nose burn severely. After several months of this I concluded it would never end and had it taken out and metal put in. What a financial nightmare.
Not planning to have any flexible ductwork in my build, and mostly planning the ducts for ventilation because my next home will be in a region that doesn't need much cooling. But best practice is never wasted!
I need to tape up the hole in the top of my furnace which was cut to put the air duct in which goes up into the ceiling and outside. What should I use to tape it up? The duct gets hot. Thank you.
you obviously get paid by the the word, there is no difference in silver or black , silver is a better product both are based on r value . black would only absorb heat in direct sunlight not from attic radiation. Panduit strap is the standard for flex connection the only superior connection is a steel hose clamp style. you are a shame to professional duct installers .
your already putting in such an inefficient system with a flex monster and duct board trash install it's hilarious to listen to you try to give tips to elevate a trash install to the next level of trash
@@HVACS maybe you should learn your trade before you try to teach others. If by heat you mean radiation then 2 flex ducts laying in the sun the black one would get hot like a black rubber garden hose does and the silver would reflect more heat but we are talking a black attic with no direct light so then black or foil flex experience the same gain from radiation due to delta T and heat moving to cold , ie the cool air in the flex ( radiation) . In this case r value is the determining factor in gain. Open an ashrea book B4 you front on me trick. Maybe you should stop confusing yourself with the properties of infared and should learn your heat.
In general shiny surfaces reflect radiant heat energy. Shiny aluminum foil facing a heat source reflects over 90+% of the radiant heat that strikes it. So a foil like material draped over the trusses will reflect the heat energy back to the roofing materials as long as there is an air space between the two.
