TimesToCome

Geekiness and life on the third coast

Saving Energy in Older New England Homes




We purchased a 100 year old home in the fall of 1997. Our first heating bill came in for October at ~$500. Since then we have come a very long way. Fuel prices have climbed about 15% a year and New England’s winters have gotten colder and a likely fuel crises is on the horizon. So we’ve stepped up efforts to keep the electric and gas bills down with out changing our lifestyles, except perhaps for the better. So far the cost of our heat has gone down 10% or more a year despite a 12-15% increase in gas prices each year. My goal is to save 60% off last years ( 2003 ) gas and electric usage. So far I’ve shaved 60% of the non-heat electric use and 13% of the gas non-heat use. Shaving 60% will put us at normal electric usage and high efficiency gas usage. I’m looking for 1000KWh electric average for each month and 1250 Therms of gas a year.
This page explains what I’ve learned, what we’ve tried, and what is on the list to try. Costs and savings are estimated on the projects we’ve completed.

General Information:

Your home stays warm in two main ways. First you wrap your home in insulation, this is like putting on a wool coat in the winter. Then you seal up all the cracks which is like putting on a leather coat or a wind breaker. Both play a large part in keeping heating costs down.

So where is your home on heating and electric usage?
US Average kWh per year varies a great deal depending on the source reporting. Most sources report about 9,500 KWh per home for electric usage in homes that do not use electric heat. A high efficiency home spends 36% or less of its utility expense on heat, some homes go as high as 58%. We were well over 58% when we began tightening things up.

To find your heat use you must first deduct non heat use, then convert to BTU’s then divide by heating degree days and the square footage of your home. Start by getting your total gas or oil etc use and electric use for the year. Most utility companies are on line now and you can look up your account with them and get the last 18 to 24 months usage.
{this last years amount that we hope to cut in half this year}
Gas (03-04): 1775 therms
Electric (03-4): 26400 KWh
Gas for washer, water heater etc 30 therms a month ( this is also the average US, you can also just use the lowest gas bill of the summer )
Electric for lighting, appliances etc was 1834 six months ago, now 1100.

Gas for heat ( 1775 – 12*30) = 1,415 { boiler with steam radiators }
Electric for heat ( 26400 – 6*1834 – 6*1100 ) = 8,796 { This is 5 oil filled electric radiators and one pond heater. }

Now we want to convert the heat units to BTUS { British Thermal Units }
Gas therms * 100,000
Electric KWh * 3,413
Propane gallons * 91,500
Oil gallons * 138,000
Wood cord * 22 million
Coal ton * 26 million

So 1,415 * 100,000 + 8,796 * 3,413 = 171,520,748 BTUs for the 03-04 winter
Now we divide that by heating degree days. This takes the high for the day subtracts the low for the day divides by 2, and subtracts 65 from that. The data is already compiled by utility companies and can be easily found online for your area and the year you are investigating. Just Google HDD and your zip code.

Providence, RI 03-04 ( 6,100 )
171,520,748/6,100 = 28,118 BTUs/HDD

Now divide that by the square footage of the heated part of your home
28,118/2,500 = 11.24 BTU’s / HDD / square foot

So how’s your home stack up?
A super efficient home uses less than 3
12% of homes are less than 5
39% of homes are between 5 and 10
24% of homes are between 10 and 15
15% of homes are between 15 and 25
10% will be over 25

I’m sure this house started well over 25, we are aiming for 5. I’m hoping to get below 10 this year and below 5 after we do the walls in a year or two.

Lighting: I had 100 watt incandencent bulbs in all the lights. The house is in the city close to other homes and has several tree around it. It keeps things cool in the summer but some of us need bright light to see. I replaced most all the 100 watt bulbs with 15 watt florescent bulbs. They cost about $5 each you can find them as low as $3 on sale or as high as $8. 17 light bulbs were switched, so 1700 watts of electricity is now down to 255, or 1445 watt savings. Of course lights are not on 24 hours a day every day. Our actual savings came to 700 KWh which is $77 a month. More than enough to cover the cost of the bulbs was paid back the first month.

Electric: Dehumidifiers eat electricity like vampires. We have no choice but to run one. We are only a city block from the river. Old homes do not have plastic vapor barriers under the concrete basement like the new homes. Buy the most energy efficient dehumidifier you can find. Turn off lights in rooms you are not using, and turn off the computers at night. Computers are energy hogs but most have built in sleep modes you can put to use. If you have a waterbed, keep it made and put a heavy quilt on it in the winter. Anything that does cooling or warming is going to be an energy hog. Buy Energy Saver appliances as you replace old appliances.

To figure out how many KWhs an appliance is using take amps * 110 volts * hours of use per month. Some appliances have the wattage listed some have the amps. For example my dehumidifier is 7.2 amps. So 7.2 * 110 = 792 watts. 702 watts * 30 days * 12 hours a day = 285120 watt-hours. Divide by 1000 = 285.12 KWh. We pay about .11 a KWh so 285.12 * .11 = $31.36 a month to run the dehumidifier.

Hotwater: We replaced our year old 30 gallon gas hot water heater that was on high with a 50 gallon HW heater on 120’F. That is saving about 4 therms a month. I’m using warm then cold in the washer instead of hot for both cycles. Also when you reach for the facet, if you are just rinsing your hands or wringing a sponge then use the cold. You’ll turn it off before the hot water would’ve gotten there anyhow. But every time you turn on the hot water facet your hot water heater is going to kick on. So now we are using 26 therms a month for hot water, the dryer and the oven which is 13% below the national average. A $15 dollar water tank wrap is supposed to pay for itself in 6 months. ( about 20 therms is for hot water, 3 for the dishwasher and 3 for the gas dryer )

Windows: The house came with the original windows. Luckily there were storms as well but they were in very bad shape. After our first fall heating bill of $500 in Oct of 1997 my first project was to seal them up better. Rope caulk is available at all hardware stores. For $30 I could do all 25 windows. This saved about 20% on our heating costs. The rope caulk just presses into the seams and you peel it off in the spring. It took about 2 days to put on and two days work to take off each spring and fall. Now we have new double pane windows. They cost a small fortune, about $20,000. They knocked about another 25% off the gas bill compared to the previous years heating bill. Mostly it is nice not to have to caulk them and they are much easier to clean and maintain.

On the windows on the second (top) floor, which loses the most heat, I placed Roman window blinds that were lined with with aluminum polyethylene. You can find this as hunter’s emergency blankets in most low end department stores. A $2 blanket does two windows. I cut panels out of the blankets and pinned them between the fabric in the shades. I also made solar collectors using black pillow cases. I put a layer of black felt in each and sewed in 5″x7″ aluminum plates. You can buy 100 of these for about $15 in the lumber store roofing section as aluminum shingle underlays. I sewed 9 into each shade. Unfortunately the sun has been MIA for 14 days now since I have done this so I haven’t been able to test them. The shades with the lining are working, you can feel the temperature difference just sliding your hand behind the shade in the morning when I let them up.

Attic: We just this month increased the insulation in the attic to R50. We went up to check and found blown in cellulose about 4″ deep. This is about R14. We also found part of a newspaper from November of 1974, the last time anyone was really concerned about rising fuel prices. I don’t yet know how much this will save us. The cost was much cheaper than anticipated, the attic has less square footage than the foot print of the house and we were able to do it all for ~$630 using the roll out fiberglass R38. Our bedroom doesn’t have a radiator in it, so we use an electric oil filled one for a few months in the winter at night. I’m hoping we won’t need that radiator this year.

Roof: The house didn’t quite come with the original roof but it was close. When it rained in the kitchen last spring that got bumped to the top of the list. It looks much nicer and was significantly cheaper than we thought it would be coming in at $15,000. The roofers replaced all the boards with plywood, laid down felt, roof shingles and a ridge vent. Much to our delight it saved 5% over the spring heating of the previous year. Had our attic insulation been where it was supposed to be we should not have noticed an energy savings with the new roof. That we did meant there was serious air leakage.

Doors: Add in storm doors where ever you can. Weather strip around the door. On a windy day run your hand around the door to find the worst air leaks and seal them. Some source estimate that as much as 20% of the heat leaves some peoples homes through leaky doors.

Basement: Ours had no insulation, of course, and lots of leaks, and leaky windows. We insulated the cellar ceiling to about R11 the second year we were here and that took 20% off the gas bill that year. This year we replaced the bulkhead door with a walk out and weather stripped it. After finding a small furry critter in the basement ( the cat is obviously too well fed ) I went around and sealed enough leaks to use 6 cans of expanding foam and 6 tubes of caulk. I hadn’t realized how much air was coming through there. The hot water pipes were wrapped this year as well. The windows were replaced with the rest a couple of years ago. I don’t remember how much the insulation cost, it was 6 years ago. I’m sure we made our money back on it the first year. The caulking and pipe wrap were only about $30 total. If the basement is much colder than the heated part of the home the heat will leak down to it from the first floor. You also need to seal around the pipes that come from the basement up through the first floor. This is what makes the floor in front of the kitchen sink and dishwasher so cold in the winter. The last couple of years I’ve run an electric radiator down there to keep things reasonable. I’m hoping to not need that radiator this year.

Sunroom: It was supposed to be a year round sun room. We had the contractor from hell and the first September I was already running heat in it. When you have high heating bills the first thing you should look at and also the cheapest is filling all the cracks with caulk. The first year we did inside and outside all the leaks I could find. We used a couple dozen tubes of caulk. Funny thing about sealing cracks is that each year you find new ones and you wonder how you missed them. It is just the previous years gaps were so much larger that you didn’t notice the smaller ones. This year I found more gaps and went through another couple of dozen tubes of caulk. The sunroom is on a raised deck. This year I also put plexi glass behind the trellis hoping for some heat gain from the sun after the leaves fall and to break the wind. Last year took 3 electric radiators to keep this room cozy, I’m hoping for two this year and one the year after. I seal the windows in this room with rope caulk, they are leaky at the seams and am considering storms. So far I am using far less heat than last year, but it is too early to tell how it will be in January.

Cracks and crevices: The insulation is like a blanket, but sealing the gaps is like putting on a wind breaker. The super efficient homes go so far as to put glue on every nail hole and wrap the home in tyvek when done. An old home may have an 5 air changes over per hour, an efficient one 1, a super efficient a half. Engineers recommend a 1/3 air change per hour for healthy air. An older home on a windy day may have as many as 30 air changes per hour. Sealing gaps is cheap, easy and gives you much more immediate savings than insulation. It is better to seal from the inside so it is painless. Every fall on a windy day and every year after the holidays on a windy day I go around the house, caulk gun in hand sealing cracks. I believe the savings are about 10% a year off the heating bill. What is amazing is that after 7 years of doing this I still find enough gaps to go through a dozen or so tubes of caulk a year. This year I did about 10 times that. Nothing like a fuel crunch to get one motivated.

You want to seal around all the window and door frames. Seal all the way around each piece of wood, wear cheap gloves, you can get a box of a 100 for a few dollars. Take your finger and run it over the caulk, pushing the caulk into the seam. Then use some of those new throw away cleaning wipes and clean the excess caulk off and you’ll never see it. Be sure to get paintable caulk if you are using it on painted areas, and clear if your wood is stained. Also seal around the baseboards, top, bottom and where ever boards meet, around light and electric outlets and fixtures. The pipes coming from the basement to the first floor kitchens, baths, and laundry rooms will also need to be sealed. Check the basement for cracks and seal them inside and out. Any of you familiar with the old triple deckers will remember the guy on the bottom floor in a winter coat, the guy in the middle comfy and the guy on top in shorts, a t-shirt and open windows in January. The heat rises and more pressure is on the leaks on the upper floors. So seal the upper floors first to get the quickest benefit. Also look for spiders, spiders like drafts so there is likely a leak where ever you find a web. A major leak in most homes is the plumbing stack. This usually runs from the basement past the baths and kitchen and up through the roof. There is usually a large hole cut around the pipe that feeds cold air down from the attic and drops in in the kitchen, baths and basement. If possible seal the top in the attic and the bottom in the basement.

On the outside of your home check all the corners. In almost every corner of this home I found a harmless looking gap. Some were a few inches across. You find them under the siding and under the wood shingles. These look like they would not go into the home but sealing them made a huge difference. Where the wood meets the basement look up with a flashlight and try poking a stick up inside. I found expanding foam to be best for sealing these leaks.

Walls: We haven’t done much yet with the walls. The siding is looking shabby so when we replace it we will have insulation blown into the walls, tyvek wrapped about the house and new siding put up. Perhaps next year. In the meantime seal all gaps, use the insulated electric covers, you can get them at any hardware store, several for a dollar. Also put the child safety plugs into the electric outlets on outside walls to stop more air leakage. Another trick I’ve found works better than insulating socket covers, instead take a piece of rope cause and press it around the outside edge of the inside of the plate, then screw the plate back in place. Cellulose and spray foam seem to be the two most popular options. If you can afford the extra money for the spray foam I’d use that.

Radiators: It seems logical to place radiators at the wall where the cold air seems to be coming in. However if you do that much of the heat is going right back out the wall. Portable electric radiators should be placed well into the room away from external walls. If you have built in radiators on outside walls you are supposed to put sheet metal behind them to reflect the heat back into the room. We are making radiator covers. As we make them I’ll put sheet metal on the backside of the radiators on exterior walls and probably a thin layer of some kind of insulation.

Programmable Thermostat: Too soon to tell how much it will save us. I have noticed that radiators that never got warm or barely warm are warming up quite well now. I’m not sure how the new programmable thermostat is doing this. When we replaced the thermostat we moved it to the opposite wall, this took it from the coldest room in the house, a double parlor on the north side, to a warmer room on the south side. Also the double parlor has 2 of the largest radiators. It may be that that room got colder faster and because of the radiators also warmed up faster. This may have been causing the furnace to cycle shorter. Shorter cycles are far less fuel efficient so this alone should save money. So far it has only been 11 days but the gas usage is 60% of the 10 days prior to putting in the thermostat so it looks like it will save quite a bit of money. I’m running it at 68′ most of the time, 60′ when we are asleep and 66′ early morning when I am busy doing chores and working out and prefer the house to be cooler.

Energy audits: Most all the utility companies will come do a free energy audit. I try to have one done every 5 or 6 years. I always get good advice and usually some low priced energy saving stuff.

Things still to try:
A solar air heater under the sunroom and in the basement, there are some great south facing windows in the basement.

Insulating the walls and wrapping the house in tyvek.

Using indoor storms on the sunroom and north facing windows.

Trombe wall: Paint the south facing basement wall black on the outside. Place plexi glass about 2″ in front of the wall extending up to the wood frame of the house, down the length of the wall and down into the ground an inch or two, seal with tape, remove plexi glass in the spring.

Transpired solar collector: Under south facing crawl spaces place corrugated black metal with tons of tiny holes in spots that are sunny and that air flows through.

Use passive solar heat collectors without a trombe wall indoors by placing clear glass containers full of black rocks in south facing windows in the winter and north facing windows in the summer.

Solar window shades. These are black plastic mesh. It is nice that even when they are in place you can still see through them. One solar site claims 225 BTU per square foot can be obtained in heat. The solar shades are the same black extruded polyethylene that is used to wrap sporting cages. You might find it much cheaper to purchase through a sporting good supplier. The smaller the holes and the thicker the net the better.

Place a windmill in back yard with generator.

Summary:
You’ll get the fastest return on your money switching incandescent bulbs to florescent, and caulking gaps. Both are easy enough for anyone to do and the supplies can be found at any hardware store. It is possible to over seal your house. However unless you have a super high efficiency, brand new home to start with it is going to be close to impossible to do so. I’ve gone through about 120 tubes of caulk in 7 years. About a third gets wiped off. Each tube seals a one foot square area 3/16″ deep. So that’s about 80 square feet or the size of 2 good sized doors. Imagine heating your home with the front and back door open all winter. And I’ve a ways to go before I’m done. All homes settle and even a year old home will have gaps that were not there and could use some filling.

Useful links:
Bay State Gas Energy Audits

Home Energy Magazine $60/year and the older articles are online.

Clear Dome Solar Air heaters I’m thinking of one or two of these myself and they gave me the idea for the solar window shades described above.

Energy guide has a tool for analyzing your home energy use and tips.

Seer, article about zero energy retro fits

Home Energy Audit do it yourself online.

Article, “Energy fixes for older homes”

Wind Turbines and Generators