In another thread I posted about my cooling problems and the fact that I went through an energy audit. At one point, I question the accuracy of the results considering a few problems in my home that, if you asked me, would seem to skew the present condition of my home.
For instance, on the first floor I have both a supply and return uncoupled and their flex-ducts sealed, but the supply and return registers are completely open to the basement below. Taking a CFM measurement reveals >60 CFM (Cubic Feet per Minute) ‘”leakage”‘ according to the person performing this audit.
Additionally, I have the ceiling for the study’s bay window completely opened up. This was the result of the September 2004 hurricane that came through Atlanta, and drove water onto the face of my home, which typically only occurs once in about ten rain events.
Part of the problem in fixing the bay window ceiling water infiltration problem caused the bedroom directly above the study to have its exterior wall drywall opened up just below the window itself. The brick-OSB sheathing air gap acts, if you asked me, as a big hole in the exterior wall on the front side of the house.
Taking these aspects into consideration in this discussion makes me wonder exactly how much ‘”leakage”‘ is present in my home as a result of these atypical conditions, versus ‘”leakages”‘ resulting from air duct ‘”leakage”‘, and ‘”leakage”‘ from canned lighting, openings in the cabinetry for plumbing, wall outlets and switches, etc.
BTW, the fireplace wasn’t considered in terms of CFM measurement as I sealed that opening to hang a flat-panel TV. Yet, the fireplace was still identified in the work-up analysis. Additionally, the doorway used for the blower-fan test was also the ‘”leakiest”‘ due to a warped door, but this was hidden because of the blower being installed in that doorway.
I am not sure if the federal program was designed to test normal conditions (doors and windows) and reveal other sources (electrical outlets and switches, fireplace openings {that were not sealed}, etc., but I can only wonder how much the program was designed to ‘identify’, the method for effectively evaluating, and the detailed solutions trained upon the auditing company to implement to homeowners.
BTW, the baseline HVAC thread documented the original estimate to seal the ‘”leakages”‘ in my home, but not the study-bedroom above study exterior wall opening. While I understood this from the get-go (no one wants to fix that problem even when offering a blank check), but how can I expect this or any auditing company to effectively meet their promise?
For instance, this company tells me they I currently have a 25% cooling loss and 31″ heating loss due to the collective measured ‘”leakages”‘, but I feel that they determined values may be skewed, and those continued existing conditions will continue to skew to a non-success completion of work. AND the last thing I want is a costly battle of an auditing company coming back saying, “we cannot meet our promise of reducing your energy loss to 5% because you have X & Y conditions unresolved.”
Sure, I accept the unresolved conditions, but then I have to wonder why they (HVAC auditor) would push to do the work (they called me last night about moving forward). And the final concern is as big of a concern as all the above: the per register measurement. The auditor performed a per register CFM test, and claimed that the loss due to ‘”leakage”‘ should be zero (0). Ok, but then he admits the measuring device cannot measure below 7.5 CFM.
I do not know how anyone else, but is the air pathways in an HVAC designed to be 100% sealed (i.e. a closed system)? No attempt to determine any ‘”leakage”‘ at the plenums was conducted. With all of this in mind and the re-quote (minus the previous quotes inclusion of two Aprilaire 5000 units) is +$4,000. And I still do not have a detailed list of the items that will be done.
For instance, how will the work be performed? If this just a sheet-metal collar and drywall seal? What about the flex-duct to collar? I suppose I could carefully look at the blown fiberglass insulation for evidence of ‘”leakage”‘ that should be tracking dust, but shouldn’t this be evident on the interior-side of the drywall-collar, too?
Ok, by now most of you will have concluded that I am not very confident in the audit and repair method, measurement, top-secret resolution, and questionable ability to meet promises by this HVAC company. As such, I am sticking to a holding pattern waiting for the jet fuel to run out and take me away to a better place. 🙂
Replies
Well, you know as well as any other that there is fraud, error and general incompetence hiding behind every tree.
be only they no longer care to hide and just take the money
"Hope and the future for me are not in lawns and cultivated fields, not in towns and cities, but in the impervious and quaking swamps."
-Thoreau
So, if a person is auditing a home with a blower-door test and leakage is pronounced as the reason for poor results then I presume evidence should be visible. Not expect visible pixie dust unless it comes in the form of dirt. :)
Wonder how they'd work on the formaldehyde laden FEMA trailers?
snorK*
"In any weather, at any hour of the day or night, I have been anxious to improve the nick of time, and notch it on my stick too; to stand on the meeting of two eternities, the past and future, which is precisely the present moment; to toe that line."-Thoreau
Some of your descriptions was VERY confusing. I take it you are describing a blower door test of your house ... that BTW had some outstanding issues of leaks to the exterior due to this damage.
They shouldn't have done a blower door leakage test until you were done fixing damage. Not sure what is going on w/ your supply/return duct. Did you do a duct blast test as well?
Generally, I think I'm understanding that you're taking the right path. No list of items that will be done ... red flag. Charge you $4K ... for what?? Guarantees with bigger holes than your house collectively has? red flag again. Don't rush into it. Your holes won't go anywhere. Get a second opinion or read up more on it. Follow your intuition.
Mark Williams, HR, OR
Yes, two tests were performed. The first one was the blower door test, which was skewed, IMO, due to the aforemented damages leading to large leakages themselves. The second test was to essentially place a negative pressure on the inside of the house and measure air flow out of a supply/return register using a menometer (sp).
The end/skewed result was a 25% cooling and 31% heating loss based on five tons worth of cooling? Two-story home with two zones (3-tons for first floor and system in basement; 2-ton for second floor and system installed in attic). First floor has one return and one supply disconnected due to construction in the basement, but I had not a problem with the first floor system in its ability to 'cool'.
The second floor was stated to have the worse leakages in the coolest room, which had the farthest runs from the evaporator coil. The room with the shortest run is also the warmest room facing NE, and is above the first floor room with said damage. Honestly, it seems like the 3-ton-1st-floor and 2-ton-2nd-floor is backwards, no?
Considering the two-story foyer and two-story family room, would these rooms subsidize the heat loading for the second floor (warm air rising, cool air falling) and in term dictate a larger capacity need for cooling--for similar SqFt floors? For instance, let's say the 1st floor is 1400 SqFt and the 2nd floor 1250 SqFt. ~450 SqFt is two-story areas.
The worse leakages for the second floor are less than half the measured rates for the disconnected supply/return regusters on the 1st floor. I need to go follow someone suggestion for calculating the heat load myself and see what comes up.
Oh, this week it has been ranging from 93-95ºF (heat index from 102-105ºF) in my area (30519; Buford, GA). The coolest room on the second floor was 78ºF and the warmest room was 85ºF. This with the HVAC running 24x7. Presently 75ºF outside and a high expected to reach 99ºF! Yeehaw!
Hey Nuke,Have you picked up a second opinion / audit on the house yet? It seems like it would be a worthwhile thing to do. If nothing else, you can compare the replies from the two companies and see how they match up.I don't recall you mentioning a timetable to get the 'known' issues resolved. It seems almost futile to proceed further until you can get those things taken care of in one fashion or another.Personally, I'm fixing up the windows and storms on my house before setting up an audit. When a partially open window is painted shut, you know you're losing conditioned air.... And in the meantime, I put a window unit in one of the bedrooms to help cool things off. Wonderful 'investment' of $150. :-)Glen
Sure have, and they thought the auditing company was a little over the top in terms of offered services for $4K. He said he could seal all of the upstairs ducts at the plenum and registers, seal the plenum, and install a 'much needed hallway return' for about $1K. Of course, saying this and writing me a quote to 'cover my arse' is another thing.
Hey, since when do HVAC companies have ethics? If I am willing to pay for a 4-ton unit for the second floor to provide me with 68ºF temps when its 98ºF outside then why not take my money? I would understand someone's unwillingness if they were wanting 75-78º temps when it was 85-90ºF outside, but to me AC is most important when it is the hottest, and then I want to be the coolest.
Even the last person said I should have at least a 3-ton unit, but will not install a 4-ton at my request and expense.
You know, I think you've got a good point there on the selective ethics of some HVAC firms.They'll gouge you this way and that, but when it comes to putting in a unit that "might" be over-sized for your situation it's "Oh no, we can't do that...."<<rant>>
I think the HVAC market would be considerably different if it were easier to work with freon and the new stuff. While I have certainly seen the ugly side of DIY work, I believe that the DIY movement in general has helped provide a control on the market rate for work. Can you imagine what would happen to prices if you could walk into your local HD, pick up the AC unit of your choice, and then install it yourself?I'll probably get flamed for saying it, but there's an artificial market there in the AC business.
<<end rant>>Are you going to take the second guy up on his bid of $1k? Get (yet) another bid?Glen
I want to, but I can't get a written quote from him--neither in paper form or email. And this person was referred to me by someone on my vanpool, which is his neighbor. Day before yesterday she called him while we rode the afternoon trip home. I guess a $1K quote of high acceptance means little in this climate where people are spending 3-10x that out of desperation.
Curious, what happens to all those evaporator coils and condensers/compressors that are 'working' but just not big enough for the job. I mean, what happens to them when they are yanked and replaced with bigger units? Could I not salvage the 2-ton 2nd floor unit for the basement, and then add a new unit for the 2nd floor?
I can see the contractor now: H3ll no, by you trying to salvage a working unit I'll miss even the slightest opportunity to charge you $3-4K to install something into your basement. I think maybe I need to get trained and licensed in this area. Business just seems too good--especially since the illegal labor can't get into it. :)
"If I am willing to pay for a 4-ton unit for the second floor to provide me with 68ºF temps when its 98ºF outside then why not take my money?"Because they don't want to listen to you complain the otehr 115 days a year when it 68* and 80% RH inside..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Bill, I though there were ways to remove moisture from the home without having to run a full-blown AC unit. I suppose had there been ways to remove moisture from the home without running an AC unit one could use that endeavor with a short-cycling super-sized system.
And while I may coin the phrase 'super-size' this is really to suggest, rather strongly, that the low-bid HVAC contractor that equipped this planned community with borderline sized units need to be better or properly sized.
I've got a secnd floor with 1229 SqFt of living space, and when I add the two-story foyer and family rooms (heat rising to the second floor) it becomes 1610 SqFt. Even the last last HVAC contractor likes to 'rough size' systems using his 'rule of thumb' of 1-ton per 500 SqFt.
So, a normal household to him is guessing 1610/500 = +3 tons. Now add the fact that I've got at least 1-kW worth of home theater equipment and 1.5-kW worth of computing equipment I presently cannot enjoy to the mix ...
There are two ways to ways to independently control moisture.One is a dehumdifier, which is basically an AC with the "hot air" dischager in the same area as the inlet. They come in not only the basic floor model, but also whole house built in system.The other an AC system with reheat. I am not sure, but I think that one way of going that is that when reheat is needed that the some of the reject heat from the AC is sent by to the cooling side AC (I think using the freon lines and not hot air).However, If you don't have sepcial humidity control needs, just want it to work on the hottest day and still function on "nomral" days a 2 stage system would be more approiate.Something else to think about would be independent systems for the HT and computer room using mini-split system(s).You need a designer, not an installer..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
I also read the OP and thought I must've missed half the thread.
If you wanted the tests to be useful, I don't think you should have done them in the middle of construction. Or at least you should've sealed up the known leaks from disconnected ducts, etc, even if only temporarily so you could get a better idea of what was going on.
And I'm still not sure that you can tell how leaky the ducts are w/o a duct blaster test. Sounds like what was done combined envelope leakage and duct leakage. The format I've seen for the blower door was to blow out and measure flow to get a spec'd pressure differential between inside and outside. Then you can walk around and feel where air is infiltrating. During a duct blaster, you seal the registers w/ sticky film, then pressurize the ducts to a certain differential and measure airflow to get that pressure. The obvious seal that likely won't be there on old construction is between the duct boot and the wall/ceiling/whatever. Leakage here is measured in the test.
We're in ATL and had a 3rd party do the blower door test before we remodeled. He also sized the AC and duct runs for a new system based on ACCA. This was based on our best guess as to how much we could improve the sealing during the remodel.
We ended up with the 2nd worst HVAC sub in GA, and the duct blaster test afterward showed 476! cfm of leakage (on a 3.5 ton system). Our tester's quote to find and fix leaks to get down to 0.05 cfm/ft^2 was $850. This is w/ all ducts in the attic and ceiling registers/returns. I ended up spending $$ on Hardcast mastic tape and fixed most of the leaks myself this spring/summer.
We haven't had the blower door done again to see where we ended up b/c there's still a decent amount of detailing to do.
And I'm right there with you- walking outside this week has been like stepping into an oven. Not real psyched to spend any time in the attic this weekend, but I think I'll have to (early AM only) to keep making progress.
I was more then prepared for the energy auditor to decline the audit based on that fact. Yet, they took my money and ran. :)
And they are willing to take another $4K to seal air leakages not related to the construction. Andd no one is willing to take money to increase the cooling capacity.
And I'm still not sure that you can tell how leaky the ducts are w/o a duct blaster test
I'm with you there. It sounds like they were using a Delta Q test to test the ducts. The DOE did study on this and deemed that they overestimated the duct leakage by as much as 55%.
IMO they should spend the money and buy a duct blaster and do the job right. Dont half-azz it with a Delta Q test.
Edited to note: Delta Q is a controversial method that some will disagree with me on.
To me its like building cabinets with a skill saw. It can be done but with what results?
Edited 8/11/2007 1:17 pm by bambam
Red Flag! Red Flag!
I just came across this and saw a lot of.......discrepancies in your audit. I am not an energy auditor- my brother does that- but I have run a blower door and duct blaster for years.
I currently have a 25% cooling loss and 31" heating loss
How much of it is inside leakage? They should have given you a breakdown on that. If they didnt test in/out leakage they didnt do their job.
Are your ducts in conditioned space? Even if they are not they (auditor) should tell you how much is leaking toward the conditioned space and how much is not. If they cant they are hacks IMO.
I have never heard the term 31" of heating loss is that a typo?
I do not know how anyone else, but is the air pathways in an HVAC designed to be 100% sealed (i.e. a closed system)?
Yes it is and it is usually not that difficult. Sometimes but not usually. The thing to remember here is you want to fix unconditioned air leakage. I dont know what he is using to measure but my duct blaster can read zero. (all four of them)
Another thing to consider is too much inside leakage can lead to your air being directed in the wrong places. which may be some of your problem. The plenum is usually the #1 culprit in this case and it should be checked and fixed if necessary. Assuming it is in conditioned space and if not its leaking to unconditioned space. Either way it should be fixed.
$4000 is too much to pay for an audit and not get acurate info. The going rate is about $1000 as it shouldt take more than 5 hours in the field and maybe 2-4 in the office. This is for an audit only which I am assumig is all you got. What were this guys credentials? Was he a certified HERS rater? I would ask to see a copy.
Check this website:
http://www.resnet.us/directory/raters_builders.aspx
If you have more questions let me know or post to renegade7101 here at BT. That is my brother and he is a certified HERS rater. He will be unavailable till next week though as he is out of town.
The audit was $450 and took a little over three hours. The $4K figure was to 'seal' the leakages, but when I asked for details (leakages located where? how the leakages were going to be sealed, etc.) the just didn't supply it. They promised to twice, but never delivered.
Hey, if they do not put the detail in writing, how can I hold them accountable? Also, the $1K figure was from another HVAC company that admitted the $4K quote company was notorious high, but that his own didn't do energy audits. His undocumented quote was to replace/seal 2nd floor ductwork and seal registers, and add a foyer return for $1K.
audit was $450
That makes me feel better on that then. I just kinda skimmed over the posts because I am feeling lazy today.
if they do not put the detail in writing
If they did a true energy audit and put it in the software then they should have a breakdown of what needs to be done. I'm thinking they dont have the software to do this with which means they are not certified HERS raters. You generally get that software from your HERS provider (every residential rater has to have one). Ask them who their provider is and get his number. If they dont have this Then get your money back or turn them in.
I saw that they stated you had 60 CFM leakage in your ducts. This is not necessarily a problem as the DOE allows 20 CFM per ton as allowable. 0 CFM is always best though and not hard to reach.
The 60-CFM leakages were from two disconnected registers, which were to be re-connected. The worse disconncted register was 30, in the master bedroom, which is the farthest run from the HVAC, and also the coolest room on the 2nd floor. All other registers measured below this.
Let me go get the paperwork and I'll post the values.
OK, I thought that was overall not just in 2 registers. Thats not good then.
Did they use a duct blaster to test or just a blower door or both? Once you test the overall leakage with a duct blaster alone then with the blower door you pressurize the house and take a second reading. All the inside leakage will recirculate and the difference is what is outside leakage.
The device they used at the registers was nothing more than a shroud with a fan-meter on it. The person said menometer, but how does one correlate wind speed to air pressure? Anyway, he used this on conjunction with the blower door fan.
BTW, the fan kept shutting off during the per-register manometer test. Again, how could this possably skew the results? Honestly, between the first HVAC guy showing up to evaluate the systems without a refrigerent leak detector (his was broke), and the energy efficiecy guy showing up with a dying blower fan (he felt it needed to be sent out for repair), I have to wonder about the industry at large. :)
A manometer is a device used to measure gas pressures. An Anemometer is used to measure windspeed.
http://encarta.msn.com/encnet/refpages/search.aspx?q=manometer
http://encarta.msn.com/encnet/refpages/search.aspx?q=anemometer
Unfortunately, I am not sure and its not written on anything. I thought he was measuring air movement, but I thought he said menometer.
A manometer would be the correct device to se to measure the difference in pressure between the house and the outside atmosphere during a blower door test. A manometer will measue very small differences in air (gas) pressure.
I am not sure, but I am under the impression that blower door tests use a verable speed fan. The speed is adjusted until you get the desired pressure difference, from the manometer.Then the speed of the fan gives the amount of air flow or leakage for the whole house.An Anemometer will be used to measure the air flow at individual registers.I don't know what kind of device that they used. But way of meausring air flow is a ventural and manometer to measure the pressure drop through the ventural..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Edited 8/14/2007 9:20 pm by BillHartmann
Yes, it was a variable speed blower, and this changed speeds until it reached a desired condition. Strange thing was he removed several pieces around the opening to maximize airflow because too much air was being sucked into the home (home the bay window problem).
Surprised that he did not tape some poly over that window so he could isolate that out..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Bill, over the months I've been on FHB I have constantly berated the shade-tree methodologies of the local yahoos in Georgia. Yet, you are still surprised. :)
Heck, I am surprised that the little f-er didn't go open a window to make the problem seem more than it really was. So, with two registers (1xsupply/return) disconnected, and two openings to the brick-air gap, I am supposedly losing 26% of my cooling capacity and 31% of my heating capacity.
Since his bid wasn't to correct the brick-air gap, and the completely open registered would be repaired, why would anyone include these in the initial calculations? Because, it adds drama to his sales game.
I've called and left messages for additional HVAC companies to commit to appointments. I'll have someone reconnect those registers, and I also began resealing those openings. I'll then go through my utility company to re-audit and see what they come up with.
There are basically a series of calibrated openings on the fan intake. Between the fan speed, opening size, and a table, that's how the auditor determines how much airflow is needed to provide the desired pressure differential. If you can't get the pressure up at 100% speed w/ one opening, you pull out one of the concentric inlet covers.
The guy who did our testing works for Southface now, so I'm not sure who you'd get (think he sold his business to a larger company). I don't know if the prices have changed a lot, but it was only $100 for us (probably $200 if you did blower door and duct blaster at the same time).
Don't know if that would break the bank, but it might give you better peace of mind about what's going on to get a 3rd party to re-do the test. Personally, I'd want to be there, too, to see where the leakage is. Plus, with our place we were able to do some cool stuff- like stuff a towel under one door to determine that half the total leakage was coming from our paneled (and drafty) bonus room over the garage.
My [skewed] audit cost me $450. Nothing is cheap in the poor south. :)