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best bang for buck energy savings?

I want to do some energy conservation/money-saving work on my early 1920's brick/stucco bungalow. The windows are all the original double-hung, weight & pulley, wood storm & screen windows. There's little or no insulation in the walls and some in the ceilings. Most of the 2nd floor is finished; what is unfinished is being used for storage. Heat is hot water radiators.

My question is where do I get the best value for my money: insulation, replacement windows, or boiler? Any thoughts on best value for a house of this vintage? I'm sort of leaning towards insulation and replacing window weights & pulleys with spring balances.

Re: best bang for buck energy savings?

How old is your boiler? Do you know the efficiency rating? I would say your priority should be windows, insulations and a high efficient boiler. So many homes have old inefficient boilers and they are just throwing almost 50cents to the dollar away on all there heat. You may also want to consider a tankless water heater like a Rinnai. They offer the highest efficiencies, endless supply of hot water and last 2-3X longer than traditional tank water heaters.

Good Luck!

Re: best bang for buck energy savings?

Insulation generally gives the biggest bang for the buck. Because you have storm windows, replacing window weights & pulleys with spring balances, insulating the pockets, and replacing weather stripping would probably do as much good as new windows and at a significant savings. If you have an old 60% boiler replacing it would cut heating costs nearly in half.


Re: best bang for buck energy savings?

The first step is to figure out exactly how much you are spending on heating and cooling. So often, people look at their utility bill as their heating/cooling bill, but there are things in the utility bill. If you have an electric hot water heater, it will be a very significant part of the utility costs.

Even when you have gas for heat, hot water and cooking, you have to separate the portion going to heat from the rest, otherwise you may have expectations that won't be met. For example, JLM said that replacing a 60% boiler could cut heating cost nearly in half.

Lets examine this a little closer. He is not wrong, but your expectations could be higher that he intended. Lets say that your winter gas bill runs $500/month and you are now expecting it to be down to around $275. But if you are using gas for hot water and cooking, $60-70 could be going for those other things. So from that, you can expect that $430 is going to heating.

Now if you select a boiler that is 85% efficient, here is your savings.

$430 * .60 = $258
$285/.85 = $303
$430 - $303 = $127

Your savings $127/month for the heating months only. Your monthly bill is now $373, not the $275 you might have been expecting. You could go for a premium boiler that is say 92% efficient. If the costs is significantly higher that the 85% system, you could be looking at diminishing returns economically. You may have other reasons, energy consciousness for example that weighs in on your decision.

There is a great book written by Charles Wing called "From the Walls In" that has an excellent primer on calculating heat loss and where the heat loss occurs. Many times adding more insulation turns out to be disappointing as well.

In his book, he compared insulation to swiss cheese. The way it is usually installed, it is full of holes. Adding more insulation is like adding more swiss cheese. The holes are still there. He didn't have digital IR camera's when he wrote that book.

Today, I would recommend that you find a service that will shoot your house on a cold night and show you where your heat losses are occurring. You can then target your insulation and weatherstripping to these losses and get the biggest bang for your buck.

In general, if you have 2-4" insulation in your attic, adding insulation there will pay off, especially if you put it in the right places. Insulating the walls could turn out to be a big disappointment.

In a typical wall, you have 10% studs, plus all the extra wood for windows and doors. An empty cavity has some insulation value, as does the sheathing. In all, an uninsulated wall has about an R4 to R5. Adding R11 fiberglass will not triple the insulation. The studs and extra wood act as short circuits for heat loss around the insulation. If the insulation isn't ventilated properly, you can loose half its value. In the end, for all the work, the R11 fiberglass may only double your wall insulation. In addition, you will probably find that the walls were only responsible for about 20% of your total heat loss in the first place.

Infiltration can be responsible for 20-40% of your heat loss. Weatherstripping and caulking can cut this in half, that would offer the best bang for the buck.

Re: best bang for buck energy savings?

Maybe try a tankless heater. It requires a small investment, but it does pay off in a few years.

Re: best bang for buck energy savings?

The first and foremost priority should be windows then insulators and lastly focusing on the boilers. Try getting an efficiency test upon the boiler and only in case of needed replacement, do you go for a replacement. Since you are planning on saving money, here is an eco friendly bulb that works on sun light. http://www.youtube.com/watch?v=_zMAWztZ6TI

Re: best bang for buck energy savings?

I have an idea that I am planning on incorporating into my breezy home. It doesn't really go along with the insulation issue you are having or windows, but it's something I am considering since I don't have the option of installing additional insulation (no wall cavity) and I am on oil. My plan is to install a pellet stove (think of a Franklin Stove) in one of our five fireplaces. Installation costs depend on a few factors.

1. The unit being installed, primarily, is the main cost. The more BTU's produced, the costlier it is.

2. Electrical wiring for the starter.

3. Flue lining, if needed.

4. Chimney inspection, if needed.

It could cost as much as $5,000 (perhaps even more depending on the unit) installed, but for someone like myself, spending on average $500 a month (year round) for the oil... during the winter months, I could potentially cut down on the oil consumption dramatically. And only using the oil to heat water and keep the pipes from freezing. Wood pellets are best purchased during the summer months when they are at their cheapest, stock up and burn it during the winter.

As far as bang for the buck, if you're spending as much as I am currently on heating oil and are unable to add insulation, a pellet stove could be your best bet. Recouping the costs will not take as long as some might think. I haven't done the math yet, so I cannot give precise numbers, but I can envision it being less than 5 years to make back the cost of installation.

If a stove in a fireplace is not an option, they do make pellet stove burners for the whole house which would replace your current source of heating the boiler (oil in my case). Pellet stoves can have up to 98% efficiency (depending on model).

Side note, these may or may not help, depending on how drafty your insulation-less home is. Home Depot/Lowes sell plastic shrink wrap for windows to seal them during the winter months. Each kit is around $10 and comes with either 5 of 9 (can't remember right now) standard window sheets.

Also, MasterPlumber mentioned tankless water heaters. This is an excellent installation IF you are NOT on oil. I don't think you mentioned it, but if you are on oil, the tankless water heater will not be very efficient and is worse off than just using a standard water heater. These heaters are mainly meant for either electric (very costly to operate) or natural gas (that's where it's efficient).

Just throwing in my 2 cents.

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