Oil vs. Electric

Factual Questions
21

Electric heating is one of the least efficient forms out there. There’s a lot wrong with oil heating (the expense of oil, the soot, the maintenance), but heating a house with direct resistance electrical heating is terribly inefficient.

You might want to consider a heat pump system if you really want to avoid oil. They are about 3.5 times as efficient as resistance electric heating, but that efficiency drops off really quick in the mid-30s (farenheit). If you live somewhere that the temperature is signficantly below freezing for a large portion of the year (and if you have an oil furnace, this is pretty likely) you’d want to supplement it with a different kind of heat, like maybe space heaters.

22

[QUOTE=The Man In Black]
I started reading up on this. But I see a few downsides. One is that this site: http://www.eere.energy.gov/consumer/your_home/insulation_airsealing/index.cfm/mytopic=11600
says that the R value of Polyurethane Insulation can drop by as much as 2 points from there example.

Another is that this company in my general area: http://www.pasprayfoam.com/Pa-Spray-Foam-inside-walls.html
Seems to say that 1" thick on foam will be R-6.5. The thickest I can go is 1.5" (just under really) on my walls. So that would be around R-9.75, which is almost the same as the R-9 hard foam I found.

Now I understand that Polyurethane dosn’t loose much of its R value in wind, like other Insulation does. The house layers from outside in are: vinyl siding, thin (1/4" or 1/8") Insulation, the old brick-tex siding (they just left it on), 1/4" wood sheets (I think), then the planks of the house. Is the R value really going to go down much because of wind here?

And last, I read that you need to use 1/2" sheetrock with it. I was not planning on useing sheetrock.
So with Polyurethane loosing R value over time, and it being about the same R value as the hard foam anyway, is it really better? Would it be cheeper?

Thank you.
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The spray foam advantage is a complete seal. I’m was anal about getting into every nook and cranny during installation and if you went that route, watch the contractor like a hawk as well. I’m skeptical of the “R” value loss. I’d say fiberglass (batts or blown), ancient rock wool and the like lose more from wetness , settling and sagging. The hard foam won’t seal as well although with all the layers you have, might not be too bad. The hard foam can’t fit the small cracks and gaps around irregular openings like windows and irregularly spaced studs. You or the contractor will probably end up using some foam in any case for those areas. Never heard about the sheetrock requirement. It may be for the high expansion foam applied after putting up the sheetrock. There may be a lot of pressure built up against the large square foot area that might pop lath/plaster for your thin spacing. My applications were to open and ancient full size 2"x4" studs. We shimmed out the walls to be square (old time construction wasn’t all it was cracked up to be), put up new lath and the plasterers took over. The application was about 1.5" thick of a full 4" depth. I’m not current on costs (also in Afghanistan).

23

[QUOTE=the raindog]
I would disagree with this. Historically, electric was more expensive than other energy sources. This is no longer universally true.
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Hear, hear! I save a bit by heating with electricity vs. gas. A significant factor in this is that I had the gas service discontinued, thus saving the fixed (non use related) cost of gas service. Also my gas heating system is outdated and the duct work is probably leaky. A modern, well installed system might well be cheaper to operate than the resistance heaters, but the savings probably wouldn’t pay for it in my lifetime, especially if the value of the capital were included.

24

[QUOTE=Kevbo]
Hear, hear! I save a bit by heating with electricity vs. gas. A significant factor in this is that I had the gas service discontinued, thus saving the fixed (non use related) cost of gas service. Also my gas heating system is outdated and the duct work is probably leaky. A modern, well installed system might well be cheaper to operate than the resistance heaters, but the savings probably wouldn’t pay for it in my lifetime, especially if the value of the capital were included.
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If you install just a new electric heating system, you’re going to be using the same ductwork that was used for your old gas furnace. Replacing all the ductwork would probably cost much more than the new electric heater. If you are planning on removing an outdated gas heating system AND the ductwork, and installing an all new furnace and ductwork system, the difference in initial cost between a new electric or a new gas furnace would be a small portion of the actual costs involved.

Leaking ductwork is really not that big of a factor in a central heating situation unless you have huge gaps in several places in the ductwork. The efficiency of the furnace is going to be the biggest cost factor as long as you have a blower adequate for your house. There are plenty of 90% or higher efficiency gas furnaces in the $1000 range. Oil furnaces run about 30% higher. Installing new ductwork can easily run over $10,000 in labor.

Heat pumps are expensive, but they also double as air conditioners (usually very efficient ones) and are much more efficient than resistance electric heaters. You’d probably make back the difference in your electric bills in two winters.

25

[QUOTE=Othar the Tooth Collector]
If you install just a new electric heating system, you’re going to be using the same ductwork that was used for your old gas furnace. Replacing all the ductwork would probably cost much more than the new electric heater. If you are planning on removing an outdated gas heating system AND the ductwork, and installing an all new furnace and ductwork system, the difference in initial cost between a new electric or a new gas furnace would be a small portion of the actual costs involved.

Leaking ductwork is really not that big of a factor in a central heating situation unless you have huge gaps in several places in the ductwork. The efficiency of the furnace is going to be the biggest cost factor as long as you have a blower adequate for your house. There are plenty of 90% or higher efficiency gas furnaces in the $1000 range. Oil furnaces run about 30% higher. Installing new ductwork can easily run over $10,000 in labor.

Heat pumps are expensive, but they also double as air conditioners (usually very efficient ones) and are much more efficient than resistance electric heaters. You’d probably make back the difference in your electric bills in two winters.
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Are you an HVAC contractor?

IME, you couldn’t find a contractor to install a 90+% furnace anywhere near $1000.

IME, leaking ductwork is a very big deal, that is often overlooked. Further, it is the cheapest thing a homeowner can do improve efficiency.

IME, the labor associated with installing new ductwork almost never approaches $10,000. (Unless it’s Warren Buffet’s house) It’s almost always much cheaper.

Lastly, electric heat is operationally more efficient than other forms of heat. It is economically inefficient. I would agree that it makes more sense than a straight A/C system for many climates, but not all. The payback period will vary.

26

[QUOTE=the raindog]
Are you an HVAC contractor?

IME, you couldn’t find a contractor to install a 90+% furnace anywhere near $1000.

IME, leaking ductwork is a very big deal, that is often overlooked. Further, it is the cheapest thing a homeowner can do improve efficiency.

IME, the labor associated with installing new ductwork almost never approaches $10,000. (Unless it’s Warren Buffet’s house) It’s almost always much cheaper.

Lastly, electric heat is operationally more efficient than other forms of heat. It is economically inefficient. I would agree that it makes more sense than a straight A/C system for many climates, but not all. The payback period will vary.
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No, I do customer service for a HVAC company. We sell gas, oil, and electric furnaces, as well as A/C and heat pumps, so I’m not biased towards one over the other. I sell equipment, parts, and supplies for all of them to the HVAC contractors. It’s funny telling them the cost for a part then overhearing them quote a price 3x higher to the homeowner in the background.

The $1000 price I mentioned was for the furnace itself, not installation. Installing a furnace using existing ductwork system would not have nearly the labor expense of installing new ductwork, especially if the system has an intelligently designed supply air plenum (when they start having to cut them open and resize them, the job gets a lot bigger). A homeowner could probably patch and add insulation to an existing ductwork system themselves without any labor expense, but you’re going to have to shell out the big bucks to higher someone licensed to install one.

If your ductwork installation for a reasonably sized house runs much under $10,000, it’s probably being put in by guys who have no training that were picked up that morning in a parking lot by the contractor. Either that, or they’re cutting you a break on the labor and charging you 5X cost instead of the more typical 3X on the parts.

27

[QUOTE=Othar the Tooth Collector]
No, I do customer service for a HVAC company. We sell gas, oil, and electric furnaces, as well as A/C and heat pumps, so I’m not biased towards one over the other. I sell equipment, parts, and supplies for all of them to the HVAC contractors. It’s funny telling them the cost for a part then overhearing them quote a price 3x higher to the homeowner in the background.

The $1000 price I mentioned was for the furnace itself, not installation. Installing a furnace using existing ductwork system would not have nearly the labor expense of installing new ductwork, especially if the system has an intelligently designed supply air plenum (when they start having to cut them open and resize them, the job gets a lot bigger). A homeowner could probably patch and add insulation to an existing ductwork system themselves without any labor expense, but you’re going to have to shell out the big bucks to higher someone licensed to install one.

**If your ductwork installation for a reasonably sized house runs much under $10,000, it’s probably being put in by guys who have no training that were picked up that morning in a parking lot by the contractor. ** Either that, or they’re cutting you a break on the labor and charging you 5X cost instead of the more typical 3X on the parts.
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I’ll tell you what, I’m that guy.

And, I am downright anal about the quality of the work we do; 24 gage metal, exceeds SMACNA standards, no 26/28 gage ever, no duct tape, no field sets, all fabricated from a professional fab shop, sealed connections, proper duct sizing, insulated where needed, rarely use flex (and R-8 when used), duct sealed joints on round pipe, supported every 8 feet or less with 20 gage hanger strap (no baling wire or slip drives) and air balanced. Getting the picture?

And we never get anywhere near $10,000 for duct work. And I have a lot of friends in the business, and they don’t either. With all due respect, your numbers aren’t right, or even close to it.

A 90+% efficient furnace will cost me [roughly] $900-1300 wholesale. I would generally not sell it without installation. An installed price would be around $3500. At any rate, even if I was willing to sell it uninstalled, I wouldn’t sell it at cost. I probably wouldn’t sell it (for liability reasons if nothing else), but if I did, it would be around $2000. (enough to discourage them from buying it from me)

28

Well, I’ve heard our authorized dealers are usually overpriced. :slight_smile:

29

[QUOTE=Othar the Tooth Collector]
Well, I’ve heard our authorized dealers are usually overpriced. :slight_smile:
[/QUOTE]

Could be.

I see prices all over the place. Some scary high, and some scary low.

Probably good to get several quotes and references!