Replyit is not a good idea to install flex in a crawl space
if you are wanting to replace the duct work then do it woth only metal and insulate it with duct wrap
Regular Guest
Hello,
Thinking about replacing all my ducts (old steel ducts, that are rusted), with new flexduct, and taking out all the ducts in my crawlspace.
1. What questions do I need to ask a contractor when they come out regarding parts, materials, etc??
2. If I may be building a 2nd floor to my home in a few years should I wait until then, in case I need to do futher major revisions to the HVAC system?
3. The heater is inside the home in a hall closet... if I add a 2nd floor, would they probably install a second heater, say in the garage for the upstairs, or redo the ductwork so the same location can "power" the entire house.
Thanks!!
Professional Member*
it is not a good idea to install flex in a crawl space
if you are wanting to replace the duct work then do it woth only metal and insulate it with duct wrap
Professional Member*
If you have a crawspace underneath the home I would recoomend that you use flex because of varmits eating holes in the ductwork. If you mean the attic crawlspace it would be fine.
Regular Guest
Thanks for the replies,
In terms of cost, how much is the cost for sheetmetal ducts vs. flex duct?
Thanks
God Speed, Jim. We'll miss you - 2-26-23
It cost more, thats all we're allowed to say.
Please read site rules. No pricing questions allowed.
Regular Guest
I think this was a typo? I believe aircooled mean to say he "wouldn't" recommend flex due to the varmits!.Originally posted by aircooled53
If you have a crawspace underneath the home I would recoomend that you use flex because of varmits eating holes in the ductwork. If you mean the attic crawlspace it would be fine.
If not, I apologize in advance to aircooled53.
regards
God Speed, Jim. We'll miss you - 2-26-23
Originally posted by biscuitnt
I think this was a typo? I believe aircooled mean to say he "wouldn't" recommend flex due to the varmits!.Originally posted by aircooled53
If you have a crawspace underneath the home I would recoomend that you use flex because of varmits eating holes in the ductwork. If you mean the attic crawlspace it would be fine.
If not, I apologize in advance to aircooled53.
regards
maybe he meant use it because its good job security for the contractor replacing it every few years.
Professional Member*
If I had pests, I'd make them "go away". But that's me.
They're partial to ductboard, though
Col 3:23
questions asked, answers received, ignorance abated
Regular Guest
Here they outlawed flex on resi just five feet on commerical so i would say go with metal and have it mastic sealed before it is insulated to get the best results.
Professional Member
maybe you guys are lucky -- I have had mice in the attic also --
use metal ducts -- unless you have the whole duct system redesigned, which is not a bad idea.
are any of the existing ducts rusted thru?
is the crawl earth covered with pvc? are walls insulated & vents closed?
read at BUILDINGSCIENCE.com
harvest rainwater,make SHADE,R75/50/30= roof/wall/floor, use HVAC mastic,caulk all wall seams!
Professional Member
Have they outlawed the sale of flex? No. Then its not outlawed, you just think it is. I just love these new rules without enforcement.Originally posted by willy1
Here they outlawed flex on resi just five feet on commerical so i would say go with metal and have it mastic sealed before it is insulated to get the best results.
"And remember my sentimental friend......that a heart is not judged by how much you love, but by how much you are loved by others" - Wizard of Oz.
Professional Member*
Left out the---------n't--------wouldn't. Been a bad week lost my brother so I guess that I'm allow a few mistakes.
The difference is that metal ductwork contracts (heat&cold) and that flex has a higher restriction rate.
But if hung and installed properly flex ductwork in attic crawlspace will work fine. But, if it is underneath the home in crawlspace that maybe cat's,possum,rats,mice,or any other varmits native to your area I DO Not recommend it.
God Speed, Jim. We'll miss you - 2-26-23
Sorry to hear about your brother.
Professional Member*
aircool
sorry for your lose.
Professional Member*
Is "No Flex" in the AZ Building Code for residences?Originally posted by willy1
Here they outlawed flex on resi just five feet on commerical so i would say go with metal and have it mastic sealed before it is insulated to get the best results.
Great! !!
Link? ...
I'll pass it on to the FL representatives.
Designer Dan __ It's Not Rocket Science, But It is SCIENCE with Some Art. _ _ KEEP IT SIMPLE & SINCERE ___ __ www.mysimplifiedhvac.com ___ __ Define the Building Envelope & Perform a Detailed Load Calc: It's ALL About Windows & Make-up Air Requirements. Know Your Equipment Capabilities
Regular Guest
Little Rock city code says no flex in residential and puts limits of 5 feet on commerical.To say its outlawed is my mistake Steve but in our company they will not do it.Not a good value to our customers.
Professional Member
willy my point is I bet the vendors are selling mountains of flex. With no enforcement the low ballers:
1. Make your company look like crooks price wise.
2. Water down the hvac economy so your company A (doesn't use flex) is always competing with company B (doesn't use flex).
What should be happening is your company A is the only bidder because company B is competing with company C (does use flex). Then when company B bids they are the only bidder because your company A is competing with company C. This way every other bid you can get top margin.
This is how the hvac economy gets watered down with rules that can't be or won't be enforced.
"And remember my sentimental friend......that a heart is not judged by how much you love, but by how much you are loved by others" - Wizard of Oz.
Banned
Check with titleless....he works on space shuttles and rockets. He can help you.
Regular Guest
It's an older 1940-1950s house...
The bottom is dirt, not covered in plastic, it would be a serious B*tch to cover it... with so many pipes and wires running around, and it's only about 18" high in some areas, 28" tall at best, truly requires CRAWLING to get around...
I was just trying to get a ballpark idea of % more for "real" ducts vs. Flex, like 2x, 3x, etc... but I guess I'll wait for some estimates...
Last year and in years past it was wet down there. I had a french drain put in which hopefully eliminates that problem.
Many ducts are rusty, but I don't know if there are any spots rusted thru.
Regular Guest
Where are you there is a Product called clean space that sounds like it could solve those problems for you.Worked on a house down here that had it done they had us come out and gut the hvac,then called us back to install after the product was put in,it was very nice they excavated under the house,leveled the ground and put in drainage and a layer of sand under the liner so clean you could have put the stuff in in a suit.1 droplight and lite up the total crawl space wish I had pics it was awsome.Think the company that markets the product is in Pennsylvania.
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