HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

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charleypartanna
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Joined: Wed May 22, 2019 5:30 pm

HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by charleypartanna »

Hi Bogleheads!

Hoping some HVAC-knowledgable folks might be able to help me out.

We'd like to get air conditioning in our 1,300SF house in San Jose, CA. We need a coil and condenser. The quotes are coming in higher than we hoped, around $10k - $11k (even a few years ago, the prices were only $7k). I think this is just Bay Area pricing, so we'll have to just suck it up. But curious what people think as these prices seem 2x - 3x what I've heard for other parts of the country.

But my main question/concerns is about our ducts. One of the companies has strongly recommended replacing the ducts because the asbestos insulation (I didn't it was asbestos) is likely being sucked into the ducts, which is of course terrifying. He says the ductwork is in bad condition and has leaks, as evidenced by the black on the insulation, which is caused by dirt being sucked into it from leaks. The estimate to replace the ducts is about $6k. What are your thoughts? I've never had duct work done, and didn't realize that duct work has a limited life. Nor do I know the last time it was replaced here. If there is an asbestos risk, we will of course have the work done before we turn the system on again. Though I'm a little skeptical because neither the inspector nor any of the other companies have mentioned the asbestos or recommended replacing the ducts. Here are some pictures (https://photos.google.com/share/AF1QipP ... RzMUR1VWx3). Thoughts?

Thanks!

Charley
Teague
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by Teague »

I'm no expert, but that looks like the usual fiberglass ducting insulation to me. How did this guy determine there was asbestos involved?

Also, the ducts supplying cold air to the house would be under positive pressure, so would not be sucking anything into them even if there were leaks.

Doesn't make sense to me, but again I'm just an average homeowner with no particular expertise in this area.
Semper Augustus
CJC000
Posts: 78
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by CJC000 »

+1 Agreed, this looks like typical fiberglass insulation, not asbestos. The taped joints could have an asbestos component but would have to be tested, not just visual. In our area it runs ~$400 for a test. Areas where the insulation is pulled off is from rodent damage. Also agree that all except the cold air return have outward pressure so would not suck debris in. The dark color is from dirt/moisture/mold. Was the replacement quote for rigid ducts or the flexible type? Flex ducting is very reasonable, the access looks a bit challenging however.
I know if a contractor says the word "asbestos" that the homeowner freaks out and will spend unnecessarily to get rid of it. Have a professional duct cleaning service come and give a quote. Don't overspend...
Chip
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by Chip »

I feel the same way about this that Teague does: that looks like fiberglass wrap. Here's a link on identifying asbestos that might be useful, though I have no expertise to evaluate what they are saying.

I would suggest that if the insulation is fiberglass, the existing ducts can probably be sealed (with joint tape) and reinsulated. There is a decent chance that the one contractor is employing scare tactics. It would surprise me if other contractors looked at your ductwork and didn't recognize asbestos.

When was the house built?
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Bengineer
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by Bengineer »

From your pix, you have "hard duct" - galvanized sheet metal, which appears to be partially wrapped with unfaced fiberglass insulation.

Your supply ducts are under positive pressure and so wouldn't suck. Black on them is from air escaping from your supply ducts into the crawl. Your returns are under negative and would suck if they leaked. Nothing wrong with hard duct. I wouldn't replace it unless it is rusted through and repair / replacing sections would be more than tearing it out and replacing with flex. You likely need to have it sealed with mastic at all the joints and certainly need to upgrade the insulation. That wouldn't cost anywhere near as much as replacement.

I think I would get a 3rd or 4th estimate. If you come to think you might actually have asbestos insulation, you could get a test kit, sample the insulation at various places and have it analyzed.
Big Dog
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by Big Dog »

we just replaced our hvac and ducts, but our ducts were flexible and crushed in parts. Much, much worse than yours which appear from the pix to just need a complete rewrap/re-insulate and seal.

Suggest you contact a local ducting company and have them just look at your ducts and see what they say.

(We started out with a few HVAC contractors for pricing and all said I needed ductwork, so I then contacted a duct contractor who also does HVAC. Price was similar, but their duct expertise was tremendous.)

Extremely happy with the results.
1rl9DS5gl2
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by 1rl9DS5gl2 »

Speaking as a retired manufacturers rep for HVAC products (35 years in the industry but retired now for 7), particularly if I lived in San Jose CA which I think has a pretty moderate climate, I'd get a quote on ductless mini split heat pumps.
Big Dog
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by Big Dog »

^^natural gas in CA is really cheap, particularly wrt electrons. OTOH, if the OP was interested in solar, then all-electric could work.
gtd98765
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by gtd98765 »

I think in most states asbestos has to be removed by a certified asbestos abatement contractor. I would be surprised if a typical HVAC company would really want to be in that business, much less maintain the training and expensive equipment to deal with it. If you are concerned about asbestos (assume your house was built before the 70's when it was banned?) you need to get an asbestos person to look at it, not an HVAC person. I also think the insulation looks like fiberglass. Maybe you are being conned. I would definitely get other companies to come visit for estimates.
LISD
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by LISD »

There is no point in getting a new high efficiency AC and then having the cold air blow into your attic (or to heat your attic in the winter) - due to leaks. At a minimum, remove all the insulation, plug any leaks, make sure they are still securely attached to the grills, and re-wrap the ducts. If, after removing the insulation, they look pretty bad, get new ducts. The new ducts that i got are round (cross section), flexible, and come already insulated (no need to wrap them).

$6k to replace the ducts is absurd. My neighbor just had her ducts replaced in her 2300 sf house for $1500. Based on SF alone, your cost should be around $1000.

While your at it, get a whole house fan. I did last winter and now I'm using it constantly. So far this year I've used my AC for maybe 5 days - only on the extremely hot days. I'm not sure how long to break even cost-wise; but in terms of comfort and efficiency they are fantastic. I wouldn't own another house without one. Total cost for your house, installed, is probably around $1200. I got a Quiet-Cool brand. On low, it's a low frequency hum. On high its a bit louder but not that loud.
Smoke
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by Smoke »

Chip wrote: Sun Aug 04, 2019 2:03 pm I feel the same way about this that Teague does: that looks like fiberglass wrap. Here's a link on identifying asbestos that might be useful, though I have no expertise to evaluate what they are saying.

I would suggest that if the insulation is fiberglass, the existing ducts can probably be sealed (with joint tape) and reinsulated. There is a decent chance that the one contractor is employing scare tactics. It would surprise me if other contractors looked at your ductwork and didn't recognize asbestos.

When was the house built?
+1 2 or 3 I lost count, looks like fiberglass to me, scare tactics I would assume as well.
Remove old insulation, reseal, install new insulation.
you have smooth wall duct now. He will most likely install the bendable accordion type, cheaper, easier and less efficient than smooth wall metal.
Arguing for the sake of arguing is something I am not going to engage in.
LISD
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by LISD »

By the way, for the lowest prices you should get quotes on HVAC in the fall or spring. August is the worst time to get a new AC - business is brisk and prices are high. If you can handle it, wait until December.
somekevinguy
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by somekevinguy »

For what it’s worth, I’ve had about 6 companies come out for estimates (Bay Area-peninsula-2000sq foot home with definite asbestos) and estimates for installing new AC, replacing furnace, removing asbestos through 3rd party, new ductwork (13 supplies), and permits/HERS testing has been in the 13950-24950 range with the most reliable companies around 16-18k.
EZ James
Posts: 110
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by EZ James »

It sure looks like glass. Any chance you could snip a sample and see if you can melt it with a propane torch or similar?
Valuethinker
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by Valuethinker »

charleypartanna wrote: Sun Aug 04, 2019 1:20 pm Hi Bogleheads!

Hoping some HVAC-knowledgable folks might be able to help me out.

We'd like to get air conditioning in our 1,300SF house in San Jose, CA. We need a coil and condenser. The quotes are coming in higher than we hoped, around $10k - $11k (even a few years ago, the prices were only $7k). I think this is just Bay Area pricing, so we'll have to just suck it up. But curious what people think as these prices seem 2x - 3x what I've heard for other parts of the country.

But my main question/concerns is about our ducts. One of the companies has strongly recommended replacing the ducts because the asbestos insulation (I didn't it was asbestos) is likely being sucked into the ducts, which is of course terrifying. He says the ductwork is in bad condition and has leaks, as evidenced by the black on the insulation, which is caused by dirt being sucked into it from leaks. The estimate to replace the ducts is about $6k. What are your thoughts? I've never had duct work done, and didn't realize that duct work has a limited life. Nor do I know the last time it was replaced here. If there is an asbestos risk, we will of course have the work done before we turn the system on again. Though I'm a little skeptical because neither the inspector nor any of the other companies have mentioned the asbestos or recommended replacing the ducts. Here are some pictures (https://photos.google.com/share/AF1QipP ... RzMUR1VWx3). Thoughts?

Thanks!

Charley
Asbestos removal is usually specialized contractor work.

Can you find out if there is a an asbestos risk assessor around (in the UK we'd call that a "Chartered Surveyor" - someone who specializes in that sort of risk?). Hoping they are independent from the contractor (who has an incentive to sell the work). I would pay a few hundred dollars to have someone check for asbestos.
ernieM
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by ernieM »

Bengineer wrote: Sun Aug 04, 2019 2:03 pm From your pix, you have "hard duct" - galvanized sheet metal, which appears to be partially wrapped with unfaced fiberglass insulation.

Your supply ducts are under positive pressure and so wouldn't suck. Black on them is from air escaping from your supply ducts into the crawl. Your returns are under negative and would suck if they leaked. Nothing wrong with hard duct. I wouldn't replace it unless it is rusted through and repair / replacing sections would be more than tearing it out and replacing with flex. You likely need to have it sealed with mastic at all the joints and certainly need to upgrade the insulation. That wouldn't cost anywhere near as much as replacement.

I think I would get a 3rd or 4th estimate. If you come to think you might actually have asbestos insulation, you could get a test kit, sample the insulation at various places and have it analyzed.
This was more-or-less my thinking as well. If the blackening turns out to be mold, I'd look around for signs of mold in other areas as well and, if necessary, do something to correct a possible moisture problem.
jharkin
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by jharkin »

Smoke wrote: Sun Aug 04, 2019 7:18 pm
Chip wrote: Sun Aug 04, 2019 2:03 pm I feel the same way about this that Teague does: that looks like fiberglass wrap. Here's a link on identifying asbestos that might be useful, though I have no expertise to evaluate what they are saying.

I would suggest that if the insulation is fiberglass, the existing ducts can probably be sealed (with joint tape) and reinsulated. There is a decent chance that the one contractor is employing scare tactics. It would surprise me if other contractors looked at your ductwork and didn't recognize asbestos.

When was the house built?
+1 2 or 3 I lost count, looks like fiberglass to me, scare tactics I would assume as well.
Remove old insulation, reseal, install new insulation.
you have smooth wall duct now. He will most likely install the bendable accordion type, cheaper, easier and less efficient than smooth wall metal.
+10000 absolutely the yellow stuff is fiberglass. Asbestos was used on pipes and it is a white material that looks almost like corrugated paper covered in glue soaked cloth that kind of looks like an old fashioned arm cast in texture:

Image

How old is the home? Typically asbestos insulation was used on boilers and pipes in old steam heating and gravity hot water heating systems installed pre-WWII. I'm not that familiar with it ever being used on hot air ducts but its possible early systems had the seams sealed with asbestos tape?

Edit: one other thought - did the installer find vermiculite insulation in your attic? That can contain asbestos and might be what he is referring to.
gtd98765
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by gtd98765 »

I'm not that familiar with it ever being used on hot air ducts but its possible early systems had the seams sealed with asbestos tape?
Our 1950's-era house did in fact have asbestos paper between the galvanized forced-air ducts and the joists. Since the ducts never get above 120 degrees F I have no idea why people thought any kind of insulation was necessary when the house was built, but it was there. We had it removed by a certified contractor for several thousand dollars; they came with moon suits, filtering equipment, etc., and a lab certified afterwards that there were no fibers in the air.
andypanda
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by andypanda »

In some limited cases asbestos was used inside of ducts.

https://inspectapedia.com/hazmat/Duct_Asbestos.php

"Watch out: If there is asbestos paper or a corrugated asbestos insulation liner inside of HVAC ducts that is likely to be hazardous. Such ductwork should be removed intact (by a qualified contractor) and replaced."

About 8 pages down...

"It's uncommon to find hemp (burlap) reinforced corrugated asbestos paper insulation inside of metal ductwork but that is certainly what it looks like to me.

And indeed in the U.S. the Illinois DEC indicates that asbestos was used as both an insulation and an air leak sealant both on the exterior of HVAC ducts and in the duct interiors."
boglesmind
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by boglesmind »

charleypartanna wrote: Sun Aug 04, 2019 1:20 pm Hi Bogleheads!

Hoping some HVAC-knowledgable folks might be able to help me out.

We'd like to get air conditioning in our 1,300SF house in San Jose, CA. We need a coil and condenser. The quotes are coming in higher than we hoped, around $10k - $11k (even a few years ago, the prices were only $7k). I think this is just Bay Area pricing, so we'll have to just suck it up. But curious what people think as these prices seem 2x - 3x what I've heard for other parts of the country.

But my main question/concerns is about our ducts. One of the companies has strongly recommended replacing the ducts because the asbestos insulation (I didn't it was asbestos) is likely being sucked into the ducts, which is of course terrifying. He says the ductwork is in bad condition and has leaks, as evidenced by the black on the insulation, which is caused by dirt being sucked into it from leaks. The estimate to replace the ducts is about $6k. What are your thoughts? I've never had duct work done, and didn't realize that duct work has a limited life. Nor do I know the last time it was replaced here. If there is an asbestos risk, we will of course have the work done before we turn the system on again. Though I'm a little skeptical because neither the inspector nor any of the other companies have mentioned the asbestos or recommended replacing the ducts. Here are some pictures (https://photos.google.com/share/AF1QipP ... RzMUR1VWx3). Thoughts?

Thanks!

Charley
We live in the same area and I think the same contractor visited our home :-) and gave the same spiel and estimates. As soon as he said there is asbestos, I knew it was scare tactics and send him his way. BTW, this guy is highly rated on yelp :oops: . He also recommended replacing our rigid ducts with flexible, pre-insulated ducts. Rigid metal ducts are much, much better than flexible ducts. They can be cleaned without damaging them. They don't crush easily. Talk to multiple contractors.

I got contractor A to remove all the fiber glass insulation on the supply ducts in the crawl space, strengthen pipe joints, apply mastic + UL approved taping (322 Multi-Purpose HVAC Foil Tape ) of joints and all potential leak areas. Costa few hundred dollars.

Had another company B clean the ducts, open furnace,blower motor, filter box, etc using HEPA vacuum and 25 to 50 feet long hoses with rotating brushes on hose ends. Remove the blower motor, fans and all grills and degrease and wash/dry and reinstall them. Ran the heater with temporary filters on all supply registers to catch any dust not caught by the HEPA vacuum. Did Total Duct Leakage test using Duct blaster. Measured the air leakage as 150 cfm at pressure differential of 25 Pa (Pascal) for a 1600+ sq feet house. Contractor was surprised that it was this low. Told him about the sealing work that was done recently. Company B Sealed the supply register boots and all intake register boots and joints with caulk and the UL approved metal tape and re-did the test and the air leakage came down to 91 cfm which is within the 2012 IECC limit of 6 cfm or less per 100 sqft of conditioned floor area.
See Basic Duct Leakage Testing Cost less than $1000. The metal ducts are in good shape and need no replacement. We are looking for a contractor to re-insulate the regid ducts with R-8 HVAC Duct Wrap Insulation (aluminum foil faced bubble-wrap, better insulation and no fiber glass).

Boglesmind
renue74
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by renue74 »

I agree with the others. That's not asbestos. I rehabbed a 1935 house last year and the water radiator heating pipes were covered in asbestos insulation.

We see these shows all the time on HGTV where they cord off the area and bring little men in white suits in. In my state, the presence of asbestos in your home does not officially require you to hire an abatement team. Using the proper clothing and mask, one can remove the asbestos insulation, bag it and then tape the bags tight. Then, there are local private landfills that will receive the asbestos bags for a fee.

In the case of pipe wrap insulation around my radiators, I did that...and the trash was about 1/2 of a trash bag that I removed. Plus the coveralls and gloves I used. Nothing special....done in about 3 hours. Didn't require a building permit. (Commercial asbestos removal is a whole different game)

I would get a 2nd opinion. New ducts in my town cost $1500. I just spent that on a new rental house rehab I'm working on. Flexible ductwork leading to a gas pack. Did it in 1/2 day.
megabad
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Re: HVAC questions: asbestos-insulated ducts need replacing? A/C costs?

Post by megabad »

charleypartanna wrote: Sun Aug 04, 2019 1:20 pm What are your thoughts?
I can't really tell what the existing condition is. Do you currently have AC? If not and they will be adding a brand new unit to your house with new electrical and drainage, $11k doesn't seem out of whack for bay area. I would say the material cost is probably 3-4k and the rest is labor and OH/P. Maybe $4k material, $3k labor and then $4k OH/P. This is what I would expect for a high end firm (with commercials and advertising and fancy lettered trucks). In contrast, if you hire a tradesperson direct and buy the material direct, I would think would maybe spend half of that all in. Of course, no fancy truck, no warranty, no service, no delivery, etc.

Having new ductwork might help you if the this is a new install (not designed for AC). $6k implies a lot of complicated work across multiple floors (or an outrageous price). I would expect very little flex duct for such a price. A one story house with a crawl should be maybe $2-3k tops in my experience. Multistory is all over the map.

I can't really speak to the asbestos because I don't know where specifically he was indicating, but I do know I would never trust an HVAC contractor to handle or identify asbestos properly. If you suspect an issue, I would likely call a remediation expert.
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