I thought I would post my initial experiences in building and living in an energy efficient dwelling .  Built in connecticut ~6500 HDD

 

OK so I finished building a house this fall and moved in Oct.  Still getting used to it.

Basic stats of the house:  28X40 ranch  , full basement with 9 ft ceilings  Basement is polysteel ICF 2.5” foam-8” concrete-2.5” foam.  Basement slab has 2” XPS under 4” concrete slab No gap.  Basement is totally inside the thermal envelope.

First floor walls 2X6 with  cellulose insulation plus 1”  exterior isocyanate insulation, ¾” airspace, 1” pine  shiplap siding.

Windows are south side= U .30  High solar gain  double pane.  East, West, North = U 0.18 low solar gain triple pane casements.   Designed for passive solar gain

 

Ceiling is drywall,3/4” airspace, 1” isocyanate insulation, then  cellulose insulation on top of that blown to R50  I used scissor trusses with an  5” energy heel so near the wall the insulation is only about 9” thick. 

No can lights in ceiling all penetrations foamed and calked.

 

Heating system is a propane boiler Munchkin 50 Kbtu Mod con + outdoor reset with a 40 gallon superstor indirect for domestic water.  There is also a solar hot water heater and 80 gallon tank that feeds the indirect .  Baseboard hot water.    

The house also has a 2 panel solarsheet  solar air heater

 

Fresh air is provided by a  fantech ERV set to provide baseline air exchange of 0.3 ACH but can be run at 3X that  if needed

 

I have a small woodstove

So far the house works great. 

 

I set the thermostat for  62° from 6-8 am,  50° from 8-4 pm, 60° from 4-10 pm and 50 from 10pm - 6 am

 

The house has a lot more thermal mass then I expected.  The lowest the temp has gone in the house is 57° overnight , that was on a day that it was 8° in the morning. 

On a sunny day with great solar gain, the house gets up to around 65°.

 

The basement has been staying at between 53 and 58 degrees with no heat input (although I put in a zone for heat if I want to add it later.

 

The woodstove can get the air temp in the house up to 80° fairly easily in about 2 hours after I fire it up even when it is 15° outside.  When I damp it down the temp quickly drops to ~72.  In the morning the temp is around 65-62 depending on the outside temp.

 

This part seems to work well.

 

I can’t light the woodstove when either the range fan is on medium or high or the dryer is running because the pressure differential back drafts it.  I can beat it by cracking a window open Once the woodstove is going, as long as the ERV is on, I can run the appliance vents without a problem with the woodstove.  I think the ERV motors naturally change the flow rates based on the back pressure enough to compensate. 

 

 When it was about 12 deg outside and the house was at 60 degrees I changed the thermostat to70 and looked at the exit water temps on the boiler. The boiler delivers water to the baseboard at around 140 degrees.  The temp in the house went up about 7 degrees per hour.  I still have not connected the fancoil unit (kickspace heater)  in the kitchen.  Without it the total amount of baseboard is rated for 18 K btu at 180° water temp so at 140 it should be running around 9-10K btu.

 So far the house efficiency seems to be reasonable.

 

I have collected  the condensate from the boiler and so far I have about 6 gallons of condensate in 3 months, so fuel usage should be minimal. 

 

 

As far as electrical usage goes, I have been averaging about 200 KWH per month.  I ran out of money near the end of building the house so I have an ancient electric washing machine and electric dryer as well as a used dishwasher and  large fridge.  I think when I have the cash and upgrade appliances and go to a gas dryer I can trim the load quite a bit. 

The lighting package is 100 percent fluorescent so that part is OK.  At some point I will look harder at eliminating some of the smaller vampire loads in the house. 

 

I wish I could find a woodstove that took a lot more wood but burned it very slowly.  The one I have has a firebox that is 9X9X16 inches and it still overheats the house

still a work in progress but good so far.

Cheers,
Eric anderson 

Sounds like you did very well on your build Eric.

 

I have a couple of questions about the, "Ceiling is drywall,3/4” airspace, 1” isocyanate insulation, then cellulose insulation on top of that blown to R50", detail.   Is the isocyanate a sheet or spray.  How did you achieve the 3/4" airspace detail?

Thanks,

Bruce

The install was very simple, on the bottom of the trusses I attatched 1" polyisocyanate sheets and taped the seams.  I then strapped the isocyanate insulation with 1X3's  (or 1x4 where the sheets overlaped) by screwing through the isocyanate and into the truss with 3" screws.  The straping was  12" OC.  after that,  you just blow in the insulation and add the drywall.  With time the iso might deflect a bit under the weight of the cellulose, but it will never telagraph through the drywall.
One of the things I did carefully was tape the iso to the partition walls  and seal all the penetrations  with foam.  In effect, I am using the iso as the air barier, not the drywall.

Cheers,
Eric

Two questions on detailing: Did you foam the sill & rim joist area, and have you done a blower door test?

Eric, good job man. It's nice to see someone put that much thought into the actual house and not focus on just the fixtures and countertops. :)

First off under the sill plate I use the foam rolls of sill sealant. Before I installed the subfloor I foamed the rim joist to the sill plate all the way around. After the walls went up I added a layer of zip sheathing over the rim joist and nailed it to the sill plate then used the Zip tape to seal it. I also use the 6” wide zip tape to seal the sheathing across the plate and to the foam of the ICF. After that I ran the isocyanate over the rim joist and sheathing but I staggered the seams relative to the sheathing. I then taped all the joints in the polyiso with zip tape also. Oh and I had cellulose blown into the rim joist area even with the inside of the ICF wall so it is about 10" of cellulose + 1" poly iso. I have not done a blower test (yet). This was actually a very low budget house. I had talked to a few energy raters about getting a blower door test, but the costs were higher then I had wanted to pay. I think after I get the new home buyers tax credit I will have enough cash left over for the blower door test. The place is still definitely a work in progress. Cheers, Eric

Hi Eric! Sounds like you did a really good job on your new home. I am actually just starting the process of designing my own. I am so glad that I found your post because how and what you built is very close to what I am looking into at the moment. I have some questions that I would love to have your point of view on, if you have the time to answer.

How long did it take to build your home?

Did you have a general contractor?

How much of the work did you do yourself?

How much propane and wood have you used so far this winter?

What brand of window did you choose?

What parts of the process gave you problems?

Would you do anything differently now?

You mentioned that it was a very low budget house, which is the same boat that I am in as well. Are you comfortable saying how much it cost? If you had a breakdown for each indviidual area that would be a tremendous help to me. Right now I am in the process of trying to make the "big picture" decisions and some real world costs would help a lot. If you aren't comfortable posting on the site I can give you my email. Personally I am going to be building a two story 28x32 home with a full, unfinished basement in VT (HDD8500). I would like to use ICF's for the basement, exterior foam, solar HW, densepack cellulose, and a woodstove. As you can see you have already built what I was hoping to! Any info you can provide would be great! Thanks.

Graham

Grahm,

I will answer the questions as best I can.  If you want more details on anything, you can just ask more questions here.

The build part of the house, from excavation of the foundation until I moved in was 14 months.  I took one month off in the middle to go iceboating so I worked on it 13 months.  On the weekends I had help from friends and relatives when I was doing things that required multiple bodies.  Typically I worked on the house  3-4 hours in the evening and 12-15 hours per day on the weekends.   I took 3 weeks of vacation time and worked long days. 

I acted as my own GC.  I did everything but  ICF foundation, cellulose insulation installation, drywall and glass shower enclosure.  I had professional help installing the boiler and the gas lines for boiler and stove were run by the Gas company.

So far I have used about 1/3 cord of wood .  It is hard to tell exactly how much propane I have used.  Not enough to make the gauge move.  I have been measuring how much condensate is collected  from the boiler (mod con boiler)  and doubling it  to get a crude idea, based on this I have used less then 20 gallons of propane so far.

In the end I used kohltech windows.  There tech people were very helpful, and I got the exact glazing I wanted on the appropriate sides of the house. 

The biggest headache for me was getting started.  I was starting with raw land so I had to go through the process of surveying, subdividing, perk tests, clearing the land, etc.  This part took me about a year to do.  The sanitarian was a real PIA and she cost me about 3 months delay for no real reason.   This got me started framing in September which I was not happy about.  I had hoped to have the whole summer to frame, but it did not happen The other big delay was getting power from the Utility company.  This took about 8 months which was crazy.  It was partially my fault because I did not know the system.  A friend who is a building in a nearby town told me exactly how to expedite the process after I vented to him. Once I did that It only took 7 weeks for them to come out.    I worked off a generator, kerosene heater and gas compressor for 8 months.  Not fun, but what are you going to do..I was fully enclosed, windows, doors roof and siding around Jan 1. 

If I were doing it again, I would tile the entrance to the house,  I used bamboo flooring and I am constantly getting snow and mud on it from walking in and the dogs.  It is holding up fine but tile would have been better.   I originally planned it that way, but changed my mind.

My total costs for the house was about 180 K

 

Basic breakdown  is as follows

Surveying, septic engineering, town permits and fees 12,000$

Costs of obtaining  construction to permanent loan and paying points for better terms ~ 5000$  + 8400$ mortgage interest payments during build.

 All sitework to include  destumping excavation,  some fill , installing septic, installing  400 ft of road, trenching for utilities etc was 42000

Drilled Well+pump+ preasure tank =4600$

500 gallon propane tank installed was 2,600$

Cost to bring in electrical power from Utility company 4,600$

All concrete work ie ICF foundation and basement floor + underslab insulation  22,000$

Framing roofing, pine siding exterior trim  was 20,000

Ridged insulation 1500

Windows were 8000

Exterior doors 1500

2 panel solar air heater  3200$

Solar hot water heater  4200$

Heating system  mod con Boiler + baseboard+ circulators+ indirect tank for DHW= 5000$

Plumbing, rough +finish= 4000

Electrical  rough in + finish + Lighting + fans  5000

Cellulose insulation   4000$

Drywall  4100

Tile, cement backerboard materials  2200

Bamboo flooring +  underlayment and supplies   4300$

Kitchen  cabinets and countertops 1600$

1000$ for stainless chimney  and parts.

The rest is paint and trim and random stuff + entry deck.  I traded a Hobie 14 for the Woodstove.    I owe a batch of people free labor for their projects in the coming years. 

 

In my case it was an expensive lot to develop because it was a long way in the woods.  I had to cut off a chunk of land  for a house lot so the remaining land could stay in the state forestry program.  The whole piece had to be surveyed.   The water table in the whole town is fairly high so there was a considerable amount of  “Approved” septic fill brought in (in part due to a very conservative sanitarian).    On the other hand,  approved lots go for about 80- 110K here in the size range I have and I got  to that point  for about 12K so I was  in good shape there.   I don’t think you ever get back what you put into extra insulation, solar hot water or solar airheater in terms of resale value so you could not build like this unless you intended to live in it for a good long while.

 

I hope this helps

Eric

Eric:

I do think you will get back what you put in for your extra insulation, solar hot water and solar airheater, esp in the years to come. No one knows what the cost of oil will be and how it will affect all other commodities. I think anyone now, especially with the Fed and State Tax Credits available until 2016 (at this date), if you compare say putting in a standard heat pump, with the Tax Credits now available it''s a wash or even less expensive. Look at the weather the U.S. is having this winter, the worst in 25 years. What money you put up front now, only saves you down the road. IMO, any home with energy efficient properties would sell quicker than one that needs to be retrofitted.

I'm building a wholehouse SIP (walls and roof, www.Eco-Panels.com) home in Western NC (I live in Fairbanks, AK) with 925 Serious Windows and geothermal heating (vertical lines because my lot didn't support horizontal). I'm at the stage of trying to figure out adding solar to offset power outages they've been having frequently this winter there. It doesn't get as cold as AK, but at 3500 ft it does get much colder than Asheville the nearest city. It's been close to 0 there the past few days. With most homes there with 4" walls and fiberglass batts, I bet there are some uncomfortable people. Why people still use fiberglass batts (I know least expensive) surprises me.

I'm also putting in a conditioned crawl. I've designed and am building as efficient an envelope as possible, forgoing all the "extra's" that most would to make the home "pretty". I can always upgrade later on down the road, if I am interested.

On your appliances. How often do you use your dryer? What I've read recently is that stay with a newer model Energy Efficient Dryer but not a fancy one. I actually have used drying racks for 30 years drying my clothes in front of our wood stove in the winter, and still hanging them to dry in the summer. I plan on still doing that in our new home. I rarely use our dryer.

I've not yet decided on a wholehouse greywater system because of the present cost, but may use the rain catchment system only at this point. I will have all entrances tiled, as I know from here with especially snowy boots in the winter, mud in the spring, a tile or vinyl floor is much easier to clean and maintain.

You're home sounds great. Hopefully now and in the future, more homeowners will get directly involved in the design and efficiency of their home. We're the ones who pay the bills when we shut the door, not the GC.

Bravo, Eric. I am very pleased to see that others are building like this. Many people thought I was crazy when focusing on details like this when building my house. Now, the house is paying me back every day. The trials and tribulations of my build are located here: www.GouinGreen.com.

Regards,
Ed

Marty,

I usualy do 2 loads of laundry per week durring the winter and one per week other seasons.  I will use a cloths line outdoors durring the summer, but I hesitate to put that much moisture in the air in the house.

I am guessing my washer and dryer are circa  1990's.  I flat out did not have any cash left for apliances so the only new one was the gas range. 

Cheers

Eric

Eric, good to hear from a fellow owner-builder. Your story is inspiring. I, too, installed a Munchkin T50 boiler (wall mount) with an indirect water heater. It's a sweet little appliance. Did the work myself and the system is working beautifully. Question: Did you calibrate the gas valve using a combustion analyzer or by simply observing the color of the flame? The local HVAC guys want $200 to calibrate it, I couldn't find a rental source locally, and the cheapest one I found on Ebay was $500. I did the best I could by eye, but would still like to measure the CO output to make sure I'm burning gas efficiently. I'm still undecided on which way to go. I'm told calibration once a year is a good practice, so maybe buying a Bacharach CA is the cheapest long run solution. Just wondering how you addressed the matter.
Clark

I had a friend check it for me with the  flue gas analyzer.  He did nt adjust it though.  Said it was fine as is.  I assume next year I will pay to have it checked.  What is kinod of funny is spending 150$ year to chekc a system that burns 100$ of propane a year.  Kind of counterproductive.

 

Eric

 

I wonder if there is a cheaper way to check the efficiency of combustion. Like, for instance, measuring the amount of condensate produced for a given volume of gas burned. As you say, spending $150+ each year to check the flue gas kind of undoes much of the benefit of buying a high AFUE furnace or boiler.