I’m trying to do my part in the green movement. The problem arises in which to do first and what would be the most effective in reducing fuel costs (Electric, NG, Water) while not taking 20 years to recoup the cost.
I’ve an older home and have been doing things over the last ten years to reduce my utility bills. However, due to loss of work (being outsourced) I was unable to tackle some of the more costlier things.
Now that I’m gainfully employed again, I can take up the banner and look into some things that would allow me to reap some of the benefits of todays newer technologies to reduce my carbon footprint.
I’ve already replaced my leaky single pain windows with low-E double pain windows. I’ve added insulation in the attic and even tried the thermal barrier (Aluminum Paint). Also, I updated my HVAC with a 10 SEER (Ten Years ago). While the new AC was 300% more efficient than
the old one, it’s a lot less efficient than the newer 14/16 SEER units.
This is the part that I need some guidance. Whether to look at having my working HVAC system replace with a more efficient one or look at having the attic sprayed with foam? While our electric bills continue to rise (currently at 13.8 center per KW), I would need to have a reasonable payback for which ever solution I choose. I started looking at new HVAC systems and they are running between 8k and 11K. I’m in the process of getting some quotes on adding the foam insulation. I’m hoping that either solution will be around thew same cost.
With a savings of 30% to 40% on Cooling and Heating bills (Dallas TX Area) it seems to me that it would take a long time to recoup the cost in energy savings. What do you folks feel would be the most cost effective to do added foam insulation or replacement of the HVAC?
The house is over 30 years old and I do plan on staying for several more years,even with the housing market softening, to down size from my existing home would cost more than staying in this house. The home is an older Fox & Jacobs (they were not known for their quality).
I’m interested in the opinions of this august group.
Sorry for such a long post.
Thanks
Replies
what kind of house?
Some have common problems that are cheaply updated.
Liberty = Freedom from unjust or undue governmental control.
American Heritage Dictionary
Sorry for such a long post.
It's not nearly long enough.
You will need to post much more info to get any real help.
But, just guessing I say the foam on the roof might do a lot for both your heating and cooling by bringing your ducting into the conditioned space.
What insulation do you have now? What's in the walls, any idea?
Joe H
Insulation costs nothing to work or run. I would be tempted to get a energy audit with thermal imaging included to take care of any "missing insulation" areas. Take care of these first because the less your cooling or neat engine runs the less impact you have from the "green" aspect.
You can rent thermal cameras from some places but its not cheap, $750 a week was the last price I got, but it would tell you where your lossing more then you should.
Maybe look at the heating/cooling unit afterwards.
Thank you folks for the replies. I'll try and give some more info.
I have 8 inches of insulation (4" of rock wool, 4" blow cellulose). I realize that they should be more but it's hard to add additional insulation in the attic as it piles up to high in some spots (cathedral ceilings)as well as covers all the wiring that is up there. I have a truss system (24" centers 2x4) that makes it hard to move up there. I had hoped that the aluminum paint (thermal barrier) would help with the heat build up in the attic.
One bad thing is I have aluminum wiring. I had an electrician come out and pig-tail copper wire to the outlets and switches. To have the wiring replaced would cost more than the house is worth. Our entire neighborhood (built by F&J) has the same problem.
As for the insulation in the walls, who knows. In some of my explorations I found what looks like 3" of fiberglass insulation. However, when I had some new phone and LAN drops run the guy said that not all the bays in the walls had insulation.
As I see it unless I want to gut the house and have new insulation put in the walls and have the attic ceiling foamed I don't have other options.
I would like to look having an energy audit performed before warmer weather hits (suppose to be 80 today). I spent nearly $4000 on electricity last year (mostly for AC). I have NG stove, dryer, DHW, and kitchen stove. I installed a programmable thermostat years ago and this has helped however, I felt that maybe I could do more. I wish I could sell the place and move to another. The housing market in our area is soft but not enough to allow me to move into a better built home for less than what I owe on this one. I've been in the house over 20 years.
I hope this will fill on the blanks and provide you folks more info to assist me with this new endeavor.
Thanks again.
Edited 2/4/2008 8:29 am ET by timby
I have been doing a lot of research on this sort of stuff for a new house I'm planning on building. I have found a lot of useful information at the FSEC website
http://www.fsec.ucf.edu/en/
I would think that our Florida climate would have some similiarities to your Texas one, but you should check with the experts to make sure. This page lists out priorities for changing your home.
http://www.fsec.ucf.edu/en/consumer/buildings/homes/priorities.htm
This should also give you ballpark percentages for figuring out your payback period for your improvements.
Jamie
Wow ! I saw that $4000 and ug. Man you have been green for a while cept it's all going the wrong way.
Your on the rite path though, keep hunting looking for some cures.
Check on the averages in your area. That sounds like a monster elec bill.
How many Sq' is the house? Wonder if the meter is 86ed.
ClayMy home is 2100 sq ft and in the North Texas area. It gets mighty hot here for 6 months (I ran the AC yesterday as it was near 80). The state of Texas has allowed the Utility companies to rape the consumer. Even though a lot of the electric companies use NG, coal, wind, nuclear, and solar to generate they were allowed to jack up the rates. I was paying 14.5 cents per KW through the summer. They lowered the rate to 13.8 for the winter months when I use a lot less electricity. I'm not looking for an over night 40% reduction/payback however, I feel it would be foolish to implement something that would take 25 years to pay back the initial cost before I start seeing a reduction in my out of pocket expenses. Also, I don't want to have to pay for a full house remodel to implement a new technology.Hope this helps....
I had to go get something done today but I was thinking about your ? system.
What size is the ac ? 4 or 5 ton.
I started looking earlier but ran out of time. What I was looking for was What is the average annual Elec bill in the US.And then for your region. Then onto the AC. I found a bunch of charts but was looking for the formula for the cost savings per annum for each step up in seer efficiency.
I'll see what I can find, may take a day or 2. But with a step up to 16 seer from a 10 I believe your in the 30% right off the bat.
So when you run your system in 100 degree temp outside what temp do you obtain inside and how much is the system running? like full time? And if so what is the outside temp get up to when the system finally has to run full time to hit the set point?
ClayThanks for taking the time to look that stuff up. I sure appreciate the effort. I really would like to get this thing started before the hot weather. Thanks
like to look having an energy audit performed
DP&L had a program for that for a while, but I've been away and out of the loop for too long to know if DP&L still exists, or has become TXU or Entergy or the like (and the mid-cities and metro areas are always different than "in town").
For the other posters, I'm guessing that they may not be assuming that you have a 2x4 framed, brick-veneered house on a slab-on-grade with a moderate-ptiched (6-8/12) roof about equal odds to be wood as asphalt shingled.
Normally, I'd tell you your best bang-for-buck in the DFW area would be insulation. But, all of your best insulation answers will tend to "freeze" your options on getting the AL wiring out. The "should you" on AL wiring really needs a good local licensed electrical type. There are a number of 70-80's era houses in the region with more than enough AL wiring to suit (if the connections and devices were installed correctly and any new work was also to a professional standard, too). But, there were scads of FnJ & similar tract builders stabbing houses into the prairie in that time, that a pro is still best.
If the wiring is ok, then, find an insulation contractor to come pump the exterior wall cavities full of cellulose from the inside. Get an insulation plane running up from the wall and under the roof to get your ductwork into conditioned space while you are at it. That R6 (mostly) insulation is not helping you heat or cool the house at all, especially to cool, not while running through a 130-135º attic.
Now, another thing you can do right now, is plant. Put in a nice row of 5 gallow wax-leaf lygustrum along the E, S, & W walls, put yaupon or a one of the "box" hedge under the windows (unless they are really low). Photina will also be good. Use deep metal edging (easier to drive into the "gumbo" soil), and use a weed fabric and a light-colored pea gravel instead of a mulch under the plantings. Wax-leaf lygustrum is almost indestructable around DFW, hugely drought-tolerant, too. It will grow as high and wide as you let it by pruning, too. It's dense shade which keeps sunlight off the house (or, more importantly, that brick veneer).Occupational hazard of my occupation not being around (sorry Bubba)
I would suggest that you contact the power company and find out if they do energy audits - or can recommend a reputable auditor.
"Going Green" and "Energy Effeciency" are the next big thing and there is already a lot of confusion, misunderstanding, and outright lies out there. Although there are many general solutions (double glazed windows, insulation, etc) IMO, there isn't a single formula, and every house needs an audit that can serve as the basis for a long range plan.
I also don't think that it's realistic to expect a quick payback. Improving energy effeciency is an incremental process and subject to the law of diminishing returns (i.e. the cost of the last 10% improvement will probably be much greater than the cost of the first 25%)
You'll also want to look carefully at the tax credits, rebates, and other financial incentives. Around here, you need to provide a signed inspection report to qualify and that means having all the right permits. One of my "almost" customers lost out on her dream of going green on an extensive remodeling job when she found out that none of the solar companies would even look at her job unless all the permits would be pulled.
#1, just a few bucks --find any air leaks (like a blower door test, smoke test) and fix the leaks. Manyu utility companies will perform that test and a retest after your fixes for a nominal $20 or so.
#2. a few dollars more, but you get a backhoe and other goodie tools out of the deal. With AC even in January, I'd think you could recoup the cost of a used backhoe AND a ground source system in a few years if you do a DIY ground source A/C system. Very effective for AC, not quite as much advantage in a warm climate like yours as a HP, but better than air when it is below 50F outside.
You can do 410A systems without an EPA freon license, and can buy all parts on the internet. (local distributors would not even talk to me except to wanting to 'recommend' a HVAC contractor) . You will nedd to buy about $300 wortht of equipment off ebay for that enterprise and do a bit of self education.
However, you will then have a $20,000 system for under $3K, plus whatever you count your new used backhoe 'contribution' toward the program<G>
a ground source system
That's going to depend on where in the DFW metro area his house is.
Over near my dad's place in north Dallas, you hit white austin chalk at depths as low as 18" and as deep as 48"--this is not fun digging even with a backhoe. Worse yet, the chalk layer is only 8-10' thick with what is locally called "blue stone" (a form of slate by color and hardness). Said blue stone is very tough on the tools, can be spooky to see rock bits on the pier drilling trucks (and bent augers).
But, out towards Frisco & First Colony, there's plenty of blackland prairie to dig through, and all you really need is a pier driller to get the depth the hvac engineer tells you is needed.
Ground contact heat exchange does have a lot to recommend it in the DFW metor area though, even if it is not very common.Occupational hazard of my occupation not being around (sorry Bubba)
Plano resident here.
Get a new electric provider. You should be able to get around 12cents/KWH in this area. We had the 14cents and recently changed. (and got a $50 Target giftcard)
Your house has an air conditioner of 10 SEER...that beats mine a bunch. Wasn't that a good standard 3 or 4 years ago?
I have 2 units. One is 24 yrs old the 2nd is 19. They are very LOW efficiency and yet my 2,300 sq ft house averages about $180/mo.
We also have about 6 inches of rockwool and need more insulation.
You must have some drastic leaks or something going on.
Also, be careful planting photinia close to house as it can suck all moisture out of your foundation. That gets you into foundation repair.
My neighbors and I have all had those headaches.
Keep us updated.
Pete
I'm starting to look at a new provider (Reliant current). They suckered me in nearly 3 years ago while the rates we starting to rise. I was told that I could lock in the current rate 14 cents and that each year after I would receive a lower rate. Well I found that it was a lie. They would charge me 14.5 cents in the summer and 13.5 in the winter. When I called and questioned them on this they told me that it average out to a lower cost per Kilowatt. I asked how does that happen. They said they charge a higher rate in the hotter months and a lower is the cooler. So it would average out to a lower rate. Well I told them they missed the fact that I used more electricity in the warmer months and a lot less in the cooler months. I'm sure that's what they fully intended. To rip the people off. I was told they had many complains and was no longer offering that plan. So as soon as my contract runs out I'm looking for a new provider. I don't want to add any additional insulation to the attic as it already to difficult to perform and maintenance up there. I was looking into having foam sprayed in the bays between the roof trusses. That way the attic space would be converted into a conditioned space. However, I'm concerned with venting the attic as my bathroom vents are vented into the attic and not outside. I gather that's another shortcut for builders down hear. The only thing is the cost. At a 30% cut in my cooling and heating it would take many years to recoup the cost of the insulation. I don't plan on living in the house another 20 plus years to recoup. My only worries about having blown in insulation in the walls is how do you know if they have performed the job right. F&J took so many shortcuts in the building process I don't know what is in the walls. I don't want to have the sheet rock removed on the inside as the cost would be to prohibited.A new high dual stage 14-16 SEER HVAC system would cost between 10K and 12K. So were back to a long pay back. My heating and cooling runs around $5000 per year. So at a 30% reduction (best case) it would take around 8 years to recoup the cost. So I'm thinking that's the way to go.I really appreciate all the comments and am willing to look at any additional info or suggestions.And for some, I'm sorry that this thread wasn't exciting as Hookers.com ....;>)
Timby,
I replaced a lot of the flexible ductwork and in doing so found many gaps where the connections were leaking or had never been tight. I also have sealed around all ceiling registers with foam and caulking.I don't think a 10SEER to the new standards would be justified. I'd love to have 10 seer. Charts show how long the payback is on 16 seer and it's way out there. Your quotes seem awfully high. Before I add more insulation,I need to put another beam in the attic to raise my sagging roof over the kitchen. This is a "custom" home built by Goodman Homes. What a crock. I put a 22 foot, triple 12 beam across the living room to raise the roof when we re-roofed. My rafters probably average 26" on center. Some are 30. With no real support in them running all the way to the ridge. 2X4 purlings over kitchen which is where rafters are sagging. 2x6 rafters!Another thing to do if you do it yourself is to put the foil on your rafters. I was in an open house on a 90degree day and the attic was 80 degrees.First thing is to fill all the holes.Pete
Thanks or the reply.One of the good things F&J did in construction (I'm sure it was by accident) was to berry the vents in the hall ceilings. They're really inside the home as opposed to being run in the attic. However, this creates some problems for air distribution. There are so many 90 degree turns and the ducts are the same size all over the house. This makes balancing the hot and cold very difficult. I'm not sure about the HVAC quotes. It's really hard to get some honest quotes and be able to compare apples to apples. When I had the HVAC replaced 11 years ago I thought that I was getting a good deal until a friend of mine that use to be in the business (commercial end) showed me how many corners were cut. I'm sure this affect the effeminacy of the unit. There is not much that can be done other than replace the HVAC and have those things changed with the new install. This may be why the quote was so high. I don't really have much to go on. I'm having problems getting folks to show up to give estimates. I gather they think I'm trying to low ball when in reality I'm trying to find someone who is dependable, does good work, and is not trying to cheat me.I had the aluminum paint done on the attic ceiling. I was told that was as good as the foil. Again I'm not sure if I was sold a bill of good or not as I had that done while I was adding another 4" of insulation in the attic. My electric bill did go down but am not sure if the radiant shield was the reason. I don't go up in the attic as there is not really that much room. I'm 6' 2" and the little insulation guys had a hard time standing and getting the insulation into the various areas.Any ideas as to what a good HVAC system should run? I'm trying to get a point of reference.Thanks
I am in Farmers Branch and face similar problems. We have not been through a cooling season yet (moved in this past November) but our gas bill is pretty high and the furnace runs constantly.I've started with sealing all the air leaks I can find. We have about 4-5 inches of insulation in our attic (some rockwool added on top of some yellowish cellulose looking insulation -- I'm not sure what it is). Our walls have no insulation (house built in 1955), and I'd like to have this done but it will have to wait until I am done rewiring everything. Like you mentioned, I am nervous about the fact that it is hard to tell what kind of job they do. As well, since our exterior is brick and we have blocking at 48" in every wall, I'm sure they would have to drill two holes in the sheetrock of every stud bay. Lead paint dust is a concern but even if it wasn't it just seems like something that is going to be a big PITA. In the bathrooms some tile would have to be removed as well.For radiant barriers, my understanding is that while both are effective, the foil backed OSB performs better than the spray on paint. I'm considering this too, but getting around in my attic is a pain also.Please do keep us updated. Since we are in the same area I'm very interested to hear what you end up doing and how it works out.David
DRHI'll do that. I'm waffling between added insulation and a new HVAC. Added insulation would make the house warmer in the winter and cooler in the summer. However, I'm not sure what other gotch-ya's will arise with trying to add insulation to the exterior walls. I know I don't have a vapor barrier between the outside brick veneer and the stud bays. I don't want a mold problem on top of everything else. It would have been nice if F&J would have isolated the slab from the ground. That way there wouldn't be so much bridging between the soil temps and the inside of the home. I find that the floors are cold in the winter and warm in the summer.It may be easier to tear down the house and start over. I just wonder how much bang i would get for my buck having the attic ceiling bays sprayed with foam and then having the existing insulation removed. I would have to have the vent fans run to the outside instead of the attic and the furnace gets it's combustible air from the attic. I would have to run a new air supply for that as well as the DHW tank as it's NG and gets it air from the attic. It's like a house of cards. If I do one thing I need to do a ton of other things to make it work ....:>(Caught between a rock and a hard place ....;>)
TimbyYou are looking into changing your provider so that tells me you are using Oncor line company. Oncor has a low cost or free program that will bring an energy auditor right to your door. They even have a program that will send you an HVAC installer to install a new unit for a discount. If you need more info just ask or email me.Here is a list of these providers:Where there's a will, there are 500 relatives
BamBamThanks for the info. I will check into that. This may be the best first step. Then I can tell where I wasting most of my heating and cooling dollars.
I'm not sure what other gotch-ya's will arise with trying to add insulation to the exterior walls.
As long as they are sheathed (which can be iffier than FnJ VB), and you mentally prepare your self for a shop-vac-hose-size hole in every stud bay, that's stil lthe best way to get blown in into your walls.
Insulation is a big ticket item, but so is a new hvac system. Getting that existing system you have into a conditioned space (instead of a very hot space for cooling) can really help.
The frustration of "gee, wouldn't it be easier to tear down?" is tough, hits all of us with old houses. Tougher when a house is too young to be that old, too.
Clean forgot to ask if you have wandering "step" cracks in the brick veneer--a common trait in the DFW area. Slab square dancing around can make other worries seem small <sigh>.Occupational hazard of my occupation not being around (sorry Bubba)
CapThat is why I had a major remodel 11 years ago. The sewer line under the house broke and wasted a lot of the soil from under my foundation. This caused the house to settle so bad we almost had to have the house condemned. However, the insurance company stepped in and we had 39 piers put in. This was followed by a 4 month renovation. I had hoped that we had covered most of the high ticket items then (New High efficiency Windows, added insulation, new HVAC). However this wasn't the case. I could have had the sheet rock removed as we where not living in the house during the renovation. We didn't know. The HVAC well.... The guys that did the install were poor at best.I still have some movement especially when it gets real dry...:>(
Great info from Danski in further post. He is correct on how techs don't always do a good job with HVAC.My neighbor had furnace and AC replaced this summer. 2,000 sq ft home and he paid $6,400 and is quite happy with it. I can get the name of the company if you'd like.Another neighbor did a complete gut and replace on HVAC. I never asked what they paid. They always deal with the same co. They used Hammick I think is the name. He lives a couple blocks from us.Pete
GotchaThis area could really use a method to find good HVAC folks. I've had several in to do services to the unit. The next to last one overfilled the unit and it was a wonder I didn't loose the compressor. The next guy came out to do the yearly service and asked why the unit had so much refrigerant. We set it back up to the correct pressures and that did reduce my bill. However, that was the time my rates jumped from 11 cents per Kilowatt to 14.5 cents per Kilowatt. So it wasn't really noticed other than the reduction in electricity usage.
Timby,
Looking at the list Bambam sent, you'd think we could find a good service. That is just a small percentage of all the companies advertising in the phone book.I have my AC serviced as needed. 5,6 or 7 years ago they condemned one unit. Said it was shot. Well it's still on the go. For how long no one knows. With the 2 units, and set-back thermostats, our costs are better than most people I talk to. This is strange since my windows have lost their seals, I need more insulation and my AC units are lowwwwww efficiency.I did get some professional coil cleaner and cleaned the condenser coils this summer. Bought it at Locke Supply on Ave K and Park in Plano. Stuff did boil out some goodies.I've used Levy & Sons to service my units and they seem to do ok. They've been in business for many years and are a large co.
GotchaThanks for the info. I'll check into that. I've not had any of the folks that do my yearly service suggest having the coil cleaned. I use 11 MERV rated filters because of allergies. Also, I check in on Levy & Sons. something folks across town are reluctant to come over to my neck of the woods to do anything. However, I'll give them a call as it's that time of year again for my HVAC service.Later
I use 11 MERV rated filters because of allergies
I hope you aren't using the standard 1" thick ones.
The 1" thick models are the only size that fits. The opening in the bottom of the HVAC will only accept 1"x"16"x25". The Merv 11 filters work great at keeping the dust down. They don't seem to restrict the airflow much.
Hopefully you change them quite often.
A 16x25 filter at 1" thick and MERV 11 is too restrictive for moving 4 tons of airflow... even worse if your blower is set for max, which is probably 5 tons.
And half the time you may see 1/3 less that in the furnace cutout to further restrict.
Got that right.
DanI'm sure that it is set to the highest rating. However, if I go to the farthest end of the duct and feel the air flow, it's not much different with the filter in or not. So I don't think there is too much restriction. I change the filters out about once a month in the summer and about every three months in the fall and winter as the furnace is seldom on in the cooler weather.
The restriction shows up when doing a temperature rise check of the furnace, or when testing the amp draw of the blower motor.
It will also show up when using a manometer to check pressure drop across the filter.
If you are able to check the RPM's of the fan, it will show up there, too.
If your ears are good, you will hear the difference.
Checking airflow with your hand is not a reliable measure of performance, but the reduction will show up with an anemometer.
Changing airflow effects the fan amp draw by a factor of 3, so small changes in airflow mean big changes in wattage.
Unless it is gasketed, the blower door gaps on your furnace will offer less restriction than the filter, so the blower is getting extra (unfiltered) air from those gaps. The dirt trails tell the tale.
Been there, done that :)
I guess my question is who do I get to check this kind of stuff (HVAC guys)?Thanks
In all honesty, a qualified and competent HVAC person should be able to perform most if not all of the things I have described.
Experience goes a long way, too.
You reach a point where you *know* that a small size, high MERV filter is going to cause problems (I don't need to test them anymore). Unfortunately, the fix is not easy, and many HVAC people claim that the filter is bad, when it is the installation that is bad.
Bad installs are frequently a result of low bid shopping or companies that have bonus incentive programs to get the work done faster. Of course, some just don't know.
"Testing" and "certification" may also be meaningless if the company does not allow the tech enough time per call to do all of the things that should be done. There is a lot of that out there.
Best of luck.
DanGetting the competent HVAC guy is a daunting task. Since all the HVAC folks that I've had contact with tell me I should have a good AC filter. They warn the consume that if they don't put these filters in the system will get clogged and burn up the compressor. So what are we to do. The manufacture should not make a unit that allows the consumer to install a filter that would burn up the major components. What other alternatives do we have than to do what the service personnel tell us to do? Also, how does a consumer know if what they're being told is right? I know if I was trained I would do the work myself. It's getting more and more difficult to get anything done without the service industry cutting corners and pocketing the money instead of doing a good job for the pay. It seems that the saying "You get what you pay for" isn't correct.
It's getting more and more difficult to get anything done without the service industry cutting corners and pocketing the money instead of doing a good job for the pay. It seems that the saying "You get what you pay for" isn't correct.
Lots of truth there.
Manufacturers just make products... filters, furnaces and air conditioners in this case. It is up to the installers of these systems to match components so the consumer ends up with a system that works as intended.
There is nothing wrong with Janitrol equipment. It is not inherently better or worse than American Standard or any other brand.
There is nothing wrong with high MERV filters... if you have the surface area to support the proper airflow. Typically, most installations do not.
But, it is possible to use a product outside of its intended specifications.
A plain old blue fiberglass filter will do an adequate job of keeping the equipment clean if it is serviced regularly... but not much for allergens.
>Looking at the list Bambam sent, you'd think we could find a good service<I can only testifiy to one company on that list and they dont do AC work. I can testify that all the companies on that list have GL (1 mil at least) and WC. These companies are contractors for TXU or whatever their name is now. They will come out to your house and weatherize it and in most cases will do it for free to the consumer. They all MUST have training and be preqalified before they ever get to bid to be contractor for TXU.And free is the BEST bang for the buck. Most of these are HERS raters or experts in this field. They will run a blower door and duct blaster and do a whole house diagnostic. You couldnt have called all on the list.Where there's a will, there are 500 relatives
I was looking into having foam sprayed in the bays between the roof trusses. That way the attic space would be converted into a conditioned space. However, I'm concerned with venting the attic as my bathroom vents are vented into the attic and not outside. I gather that's another shortcut for builders down hear.
Thats not good practice even by the tract builders. But, it is correctable, you just plumb the vent to the outside, to a gable if you have one, soffit if your overhangs are deep enough, or, least-best, through the roof. But, out Now beter than later.
30% cut seems very low. The structure we renovated jsut west of the river had an attic temperature that peaked about 87 last year. That's versus 137 recorded before foaming in. That building was foamed to R30-35 in the bays and 1.25-1.5" thick over the roof framing. Now that the walls are fully insulated (blown-in cellulose), we'll see how that affects the utility bills. Now, there has been a problem with that house--finding the right balance for running the a/c. (And harder to find techs with just the right finesse, too.)Occupational hazard of my occupation not being around (sorry Bubba)
Best Bang for the Buck
I thot this was gonna be a really informative thread for me ...
oh well ...
Jeff
Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Jeff, I think you're looking for the Craigslist hookers thread.........
Joe H
that would explain it!
thanks,
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
I was going to suggest Kathy (or Cathy as the case may be) when saw the thread title. Boy, was I off.
TFB (Bill)
Kathy or Cathy ...
which ever one U think would be best!
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
What about a green (as in plants) roof? I dont know a thing about them, but I like the idea.
look into some solar screens for any window that gets significant sun in the summer.
have a blower door test performend and fix any air leaks you can.
If you can get the air handler and duct work into conditioned space, that will save you about 30% on your cooling bills.
Another perspective...
You mention that you are planning on staying several more years so maybe a large outlay of cash updating insulation or the A/C would not get paid back by savings on your electric bill in that short a time.
If you are looking to lower your electric bill, and depending on how you use your house, you could get a window A/C unit or two to cool your most used rooms and raise the temp on your whole house thermostat. I don't think this would work very well if you did more than two window units.
Well, going from 10 to 12 SEER usually amounts to somewhere around a 20% potential savings over 10 SEER. The new minimum standard of 13 SEER will give you a little bit more.
Now, SEER ratings include the whole duct system- it is not merely decreased energy consumption. A more meaningful comparison is the EER ratings which tells you how efficient the appliance is delivering a BTU for each kW of electricity.
Things like poorly sealed ductwork (or flex connections to the duct collars) will have a huge impact on efficiency (the SEER part). Leaks in the return side are even worse because the system now has to condition 120*+ return air instead of something around 77* return air. Gaps around the air filter access can allow 10% of the total system return air to come from the attic.
Poorly sealed return ducting can account for an easy 30% loss of cooling capacity.
Poorly designed and installed ductwork incurs more internal losses.
If your 10 SEER system does not have a TXV valve, that will bump efficiency (SEER) to about 12.
New systems have a TXV valve to meet SEER requirements, but some manufacturers are getting by with a piston. Always get a TXV valve.
One of the biggest things you can do is replace your air handler/furnace with a model that has a variable speed blower motor. These use *much* less electricity that the standard PSC induction motor*. Adding a TXV valve will put you close to 14 SEER due to the ramping characteristics of the variable speed programming (you cannot get 14 SEER without a VSD, even if the equipment is rated for 14 SEER).
*A VSD motor knows electronically how much CFM it is delivering due to an internal feedback loop. If your duct system is restrictive, the VSD motor will attempt to maintain a higher RPM to produce the required CFM. This can result in an increase in energy use. A PSC motor is "dumb" in comparison, and only knows the selected speed tap.
Making sure that your existing fan is set for the proper speed will save big bucks if it can be slowed down via a different speed tap.
Making sure that your existing air conditioner is charged properly can make a huge difference. Overcharged is as bad as undercharged. Lots of "techs" can't properly charge an air conditioner, nor do HVAC companies typically allow enough time with the "git 'er done" mentality. Under and overcharging both allow for increased run times, which costs money.
Sealing your home with foam will require forced ventilation for fresh air, and an ERV to keep added costs due to added infiltration low.
I would:
Install an air handler/furnace with a variable speed motor.
Install a TXV valve.
Make sure existing AC unit is charged properly.
Make sure ducts (supply and return) are sealed.
Use mastic (duct sealant) *under* the flex connection (ie: between the metal collar and the duct). Seal the collars to the duct first, wait a day (or 2) to dry, then attach flex. Duct connections under the insulation (ie: metal duct) also need to be sealed. Thinking that the insulation seals things is a common misconception- and insulation can hide shoddy work
Make sure the air filter has a gasketed door.
Make sure all flex in the attic has a minimum R6 value, and I would not hesitate to use a higher R value.
A reasonably competent homeowner can do duct sealing and flex replacement. The materials aren't too expensive or exotic, but it takes a whole lot of time.
Anything less and you are wasting time and money. Anything more will be a waste of time and money until the basics are addressed.
Attic systems work fine if there is attention to detail.
Edited 2/5/2008 3:39 pm ET by danski0224
OK, now I'm curious....What's this TXV valve and how do you install on older units?Pete.
TXV valve is a thermal expansion valve. It regulates the flow of refrigerant based on temperature instead of pressure through a fixed orifice.
It allows only the proper amount of refrigerant into the evaporator (indoor) coil for maximum efficiency. This reduces amp draw for the compressor and allows best performance in low cooling demand applications.
It can be retrofitted to any fixed orifice residential a/c system... refrigerant must be reclaimed first, though. Brazing is required.
A biflow valve must be used in a heat pump application.
The valve and sensing bulb must be installed properly so it works right.
DanWouldn't all this work cost a lot and I would still end up with an 11 year old unit that was poorly installed?I do appreciate the input. I think I'll look into an energy audit and go from there. That should give me a better idea of where I'm loosing my house seal.Thanks
"All of that work", exclusive of equipment replacement, is needed to ensure that what you have is performing the best it can. Installing nice new 14 or 16 SEER equipment on poorly sealed, installed or insulated ductwork is a waste of money, and will not return the results or savings you seek.
A reasonably competent homeowner can seal their own ductwork at considerable savings because it takes so long to do it- especially as a retrofit. The same goes for replacing flex runs and replacing duct insulation. That work is not difficult, just terribly time consuming. Remember, flex runs must be sealed to the duct collar, and the duct collar must be sealed to the ductwork, or else there is an air leak. Putting duct sealer on the *outside* of the flex connection does no good.
Making sure that the airflow is the best it can be is the first step. Long flex runs should be replaced with insulated metal ductwork where possible. Duct fittings may need to be changed. Bad duct design near the air handling equipment is the worst.
Sealing your ducts and making sure they are well insulated is the next step, and you will get the most bang for the buck.
Then, make sure that your current AC unit is operating properly (clean and properly charged).
Those three things above will give the best return for the lowest possible cost.
Best performance = most efficient operation = lowest cost of operation.
In your first post, you indicated that a SEER upgrade may not be worth it. The only way to ensure that your 11 year old unit is working properly is to have it serviced by someone that knows what they are doing, not a gas and go outfit.
Properly serviced means cleaning the outdoor and indoor coils (when accessible) and setting the charge properly.
Older 10 SEER equipment was much more forgiving than the new 13+ SEER stuff. The "beer can cold" charging methods do not work anymore (they didn't work then, either), yet if contractors in my area do it, then it is reasonable to assume that the practice is still done elsewhere. It can easily take an hour to set the charge on a unit, so the $69.00 "clean and check" special aint gonna cut it.
Adding a TXV valve to that existing equipment is the best way to improve performance without replacing it. It will not be cheap because the system needs to be reclaimed, opened, evacuated and recharged. You would have to evaluate the upgrade $$$ -vs- replacement $$$ dilemma.
The recent 13 SEER mandate can make equipment replacement extremely expensive- especially if your existing stuff is 3 tons or larger. That break point is when a new copper lineset will be required because the existing lineset will be too small.
Contractors responding to *customer pressure to keep prices low* will leave out this critical step (lineset replacement), resulting in poor performance and early equipment failure (but, it will last for the standard 1 year warranty, so the customer is SOL).
Rising R22 prices due to the 2010 phaseout and current shortages will increase future service bills.
A few poorly designed duct fittings will cause huge airflow reductions, therefore reducing system performance.
Duct leakage on the return side of an attic duct system cannot be overemphasized. That leakage must be eliminated.
According to a chart based on 2002 electric rates in the Dallas area, a variable speed motor will save (compared to a standard PSC induction motor) a minimum of $80 per year, and $210 per year if the fan is left "on" all the time. If those rates have gone up since then, then the savings are greater. The variable speed upgrade is well worth it.
Better home insulation can change equipment size requirements, so you need to do that or rule it out. Then, buy the most efficient equipment you can afford... after everything else is up to snuff.
Unfortunately, most consumers view HVAC as a commodity to be purchased for the lowest price. Contractors have responded to this philosophy by installing to minimum standards the first time around. Repairing it later so the system works properly just costs more money when the repairs are done, and each time the system is used over the life cycle of the equipment.
Customers evaluating HVAC systems based on a line item bid price often choose poorly.
DanI agree. Most consumers look at the bottom line first before buying. However, I try to evaluate my needs first then try to be an educated consumer. While not looking for the lowest cost, I still want a good product when I make my purchase. I typically don't by the highest end but like something that gives me good performance without a lot of maintenance headaches.I would like to have a person, that can be trusted, to look at my current HVAC system and give me options on what to do next (based on reducing electric bills). I realize there needs to be some repair work done to the connection between the AC coil and the duct system. I don't need to have the ducts sealed as they are a part of the ceiling and are more a path-way and not flex ducts. This system has some inherent problems as the ducts do not go from larger to smaller to compensate to air flow. Next I would like them to explain the difference of adding this variable speed upgrade as well as the TXV vs a new system. Problem is most of the folks that I've dealt with in the past would rather sell a new unit that make a lower cost alternative that would give me the same effect. My current HVAC is a Gas furnace around 80k -100k BTUs with a 4 ton AC(R22). I believe the unit in an American Standard but may be a Janitrol. There was some heated discussion with the install as to what I was suppose to get (what unit was quoted). I believe I got a Janitrol instead and they gave me back some money and added a 5 year warranty.This is moot ... I need to have the unit serviced anyway. Can you make a suggestion as to who I could use to give me an estimate on the work you suggested?
How are the ducts part of the ceiling? Care to post a picture or drawing?
If the duct run is short enough, reducing trunklines are not always required. A compromise, but it still works.
For all practical purposes, it is almost impossible to retrofit a variable speed drive blower motor to an existing piece of residential equipment. Unless you can get the parts really cheap (motor, control board, wiring harness), it will be cheaper to replace the furnace with one that has that type of blower motor from the factory.
Because there was a Federal Tax Credit on electrically efficient furnaces and air handlers last year, you are assured that they use less energy. By definition, electrically efficient equipment has a variable speed DC blower motor.
A TXV valve is an easy upgrade to a new system- do not get one without that valve. Almost all 13 SEER systems have one, and I suspect all 14 and up systems have one.
If you were quoted AS and got Janitrol, you should have been refunded a lot of money. I would guess at least 15%. Either brand will work fine if it is properly installed.
One obvious question would be is the AC unit properly sized? In other words, has anyone done a load calculation? You can go to http://www.hvac-computer.com spend $50 and do it yourself. If it is too small, it will run constantly and never maintain the setpoint.
Keep in mind that residential AC systems are rated at an 80* indoor temperature. If you like it colder, that can impact unit size, and it will lower the SEER rating.
There is no way I can help with your local contractor search, as I am located about 925 miles northeast.
You know the questions and you have been given good answers. You will have to evaluate the contractors you select to look at the job.
Best of luck.
DanF&J created a drop ceiling in the halls to use as the ducts for HVAC. These drop downs are constructed of a fiber-board. They are large compared to most existing ducks. While they enable a large amount of air flow they are not conducive to allowing the flow of cool air to reach the end of the line with any velocity. This effects the comfort levels in the various rooms. The only way to control is through the room vents. They can be opened wider or closed to assist in balancing the system.I didn't get anyway near 15% rebate. We had a serious fight just to get the system installed. The unit is 4 tons. whether is the appropriate size is just a guess. I know they didn't do a log calculation. They just used the existing size of the original AC (30+ year old 3 SEER).We are more concerned over cooling than heating. Eighty degrees would be too warm. I typically keep the AC set to 75 in the summer when we are home. I have the program set to raise the temp to 79 when we are not there and it lowers the temp to 75 just before we come home from work.They are more HVAC companies than you can shake a s=tick at down here. Most are the Gas-n-Go types. Like I stated in an earlier post, I wish there were a list of good HVAC folks in our area. So many companies come and go as well as merge with other companies. That's how I got suckered in the deal. I had use the company several times in the past with the older AC unit. They seems honest and were very good to work with. Then they were bought out by a bigger company. well I contacted them to give me a bid. The original guy that came out to give the estimate was one I had worked with in the past and trusted. However, when the crew came out to do the install things started to go wrong. So, I haven't done business with them since....:>(
residential AC systems are rated at an 80* indoor temperature. If you like it colder
No worries for that around DFW, DeltaT versus ambient means you can only cool to under 80 about 4 months the year any way (typically April-May & Sept-Oct).
Ok, that's not fair, DFW norms are around 95-96 at 30-40%--75º is an achievable indoor temperature, just expensive if you want every bit of that 20 DeltaT for 40-60 days it stays that warm.Occupational hazard of my occupation not being around (sorry Bubba)
I'll say insulation is almost always the best place to start, especially attic insulation since it's so easy to get to. Go big. R60 isn't too much. Spray foam is great. A few inches of spray foam on the underside of the roof combined with fiberglass or celulose to keep costs down. Seal all the small verical gaps and holes that leak air in places you don't want. There are lots of small gaps and holes in any house and old houses could easily take one person 50 hours or more.
Cheers
Beer was created so carpenters wouldn't rule the world.
1. Close off the air leaks including the little foam gaskets behind receptacles and switches.
If you have a fireplace, check the seal with the vent closed; plastic over the opening will give you an idea of how much air is coming in/escaping.
Check around the windows; really common for there to be zero insulation.
Probably the lowest overall cost step that will really reduce your heating/cooling costs.
2 (well maybe 1). Have the HVAC service including cleaning the inside coils; money well spent. Dust/dirt here dramatically reduces efficiency.
3. Insulation in the attic. I've seen the religious wars here over whether to hot roof or not; your call.
Send the bathroom vents outside regardless of how you insulate. Sewer gas is flammable/explosive! Why take the chance?
4. Properly insulate the walls. You need not pull down the drywall. There will be holes to be patched by you or the contractor. Your call on densepack cellulose or foam. here is where you need a reputable insulation contractor that will do the job right.
5. I went to fluorescent bulbs wherever possible and saw a real reduction in electric cost. Some people don't like the quality of the light but use less electricity.
Take a deep breath.... any money left? You can probably take a break right here and see what's happening to your energy expenditures.
Based on the energy cost numbers you listed earlier for your size house, you should see at least 30% reduction in your HVAC energy costs and I wouldn't be surprised by 50% reduction.
How do I know? I live in Central TX and have done a lot of this; I'm not done yet.
Now you can consider high cost / long payback items like modern insulated windows and high SEER air conditioner units.
Good luck,
Marc
MarcI put those light and outlet plate gaskets on after I had the house renovation 11 years ago. Also, I've been replacing my old light bulbs with CFL's. I get my HVAC serviced every year. There is only so much you can do with a bad installation. This is one of the reasons I'm looking into getting a new HVAC. I don't think the system was matched well. I was told I was getting a good AC and ended up with a low cost builders special. The install was poorly done. If money wasn't a concern, I would have the sheet rock removed (on the inside) for all the outside walls and have foam insulation done. Also, I would have the existing attic insulation taken out and have the bays foamed in the attic. Then I would have the bathroom and kitchen vents run to the outside. Finally I would replace my HVAC with a new dual stage High Efficiency one. However, I don't have the $30k to do all that....:>(
I do not have time to read all of the good suggestions but do you have a good continious ridge vent on the roof, My sisters house has an attic living space we put one on and it lowered then indoor temp by ten degrees. When I cut the slot for it the attic space exhausted like a chimney.
Not as nice as AC but another thing we did on her house was install a Swamp cooler. It would of been thousands for Ac, she has hot water heat and no existing duct work. One Hvac guy said "have you thought about a swamp cooler"? We all stared at him he said "no I am serious, we did it to the Moore mansion down the street, got the biggest one made installed it on the roof". Even said "heck you guys know what your doing do it yourself", I would be glad to selll you a ten thousand $ ac system but all you need is a cooler. Did it they have been happy.
They work in parts of texas don't they?
Wallyo
They work in parts of texas don't they?
Out in the far West, parts of the Panhandle--I'd have to go search up a humidity average chart for the State. For most of the most-populated areas--no, too humid too much of the year.
And, too me, Dallas-Ft Worth is dry, about an order of magnitude drier; Lubbock an order beyond that. A person needs to be well armed with numbers around this place, after all, it's not but 800 x 700 miles across. <g>Occupational hazard of my occupation not being around (sorry Bubba)