New Home Build. Need Suggestions.

[KMR]

Hello everyone,

I have recently started reading this forum and am very happy with the information available here. I am planning a new home build in the next couple of years and figure the more planning I put into the build the better. From the reading I have done I plan to make as much use of insulation and passive solar concepts as possible to reduce the overall energy requirements for the home. I would like to use radiant in-floor heat so that I can heat with low temp water. I would like to build the house in stages so I was thinking of an oil or propane boiler to start with and add a wood boiler with (non-pressurized) storage and solar hot water. The idea being that a propane boiler would have a small upfront cost and as I got more funds I could add the wood boiler, storage, and solar hot water which would leave the propane boiler as a backup for the wood during the winter. I have the land now with an unlimited supply of wood and the ultimate goal would be to get all heating and DHW from a combination of wood and SHW with propane as backup. I love cooking with a propane stove which is why I considered a propane boiler as the initial heat source which would then be phased into the backup unit. The lower the monthly payments the better!

I enjoy wood heat and have an unlimited supply of it which is why a wood boiler seemed to make sense in this situation. However I would like to have air conditioning an some point which means ducting (I can put that in unconnected during the initial build). I am a bit overwhelmed with discussions of Heat Pumps although I understand they would be a good fit for my eventual air conditioning requirements. I am hoping for some suggestions of further reading based on the requirements listed here. Maybe wood doesn't even make sense for me, or maybe the cost propane doesn't make it worth while (even though I love a propane stove). I'm open to all opinions / options as the build is still a way off; I just want to get as much information as possible before I start so that I get the maximum benefit from the planning. Another consideration is power outages; I would like to have heat and DHW without power but it isn't essential.

Thanks!

 

[Fred61]

I've said it before and here it is again: If I were building new now the structure would not need a wood boiler at all!! Perhaps a couple mini splits for cooling and heating and perhaps a masonry heater along with a small propane boiler. Super insulate, orient, use high mass building products and keep the heat from escaping with window coverings.
Build your house high and dry to keep any moisture from wicking heat away from the foundation. Don't skimp on crushed stone and course gravel for backfill. Crushed stone is about 90% compacted as dumped and spread so lay plenty under foundation and slab and then compact.

 

[Fi-Q]

Are you going with a full basement ?

I did. And i got the inside wall sprayed with 2in of sprayed foam (heatlok soya) from the footing all the way up to the crown. And I put 4 in of foam with my tubing, and then got the basement slav poored. A very well unsulated non humid basement.

1 thing i would do diffrent is to go with at least 8'6'' basement wall. I have 8' only, minus the 4in of foam and the 4in slab I only have 7'4'' left.... And once I add flooring and ceiling, i'll have less.

The only cons to this super insulated basement is I don't get any basement cooling effect in the summer time. I guess I'll need AC eventually.

I am going with radiant floor. But the final decision haven't been made on the boiler yet, but it looking for a yes. Once I had a 28x50 shop that I want heated year round, the boiler will make more sense.

I went with double studed wall and a combination of int/ext sheating with straping for a supposely total of R36 for the wall and 20 in of blow in insulation for the attic for a R60 value.

Still a lot to do.

One thing I can recommand is plan, plan and plan. I toughr I was ready to build after years of thinkerinf, but i was not. Ober rhink everything twice ( heating, ac, alarm aystem, windows, sun heat, electric outlet, ect....)

 

[jebatty]

Fred61, your mini split one solution fits all is interesting. Can you refer me to units that can do the job in the well below 0 temps of northern MN? We may have extended periods when the temperature does not even get above 0F in the daytime, and night temps can range down to -30F and lower. I was of the understanding that an air source heat pump bottoms out on operation at something around +15-20F, but if they can operate efficiently into the below 0F range that I experience where I live, I would like to research that further. Thanks.

 

[KMR]

I am planning on having a full finished basement. I live in Atlantic Canada and we can get as low as -30C but the average is somewhere around -10C to 0C in the middle of winter. Would mini splits be a good option if I wanted to heat a garage, hot tub, and the like later on? I plan on building this house and never moving. I understand the system that I have described might be overkill but I am trying to keep future expandability in mind for when I have a family and random projects. My concern with using electricity and propane as the primary sources of heating / air conditioning is the ongoing monthly costs they represent. I am a programmer and would like to build this house and then do contract programming so I can work as little as possible, so I would like to keep ongoing monthly bills as low as possible because I would only like to work a maximum of six months a year (or less!).

That being said I am willing to consider all options and I understand that the system I have described here may not suit my needs very well. I am still in the very early planning stages.

I appreciate all of your input!

 

[willyswagon]

Where in Atlantic Canada?

 

[KMR]

Nova Scotia

 

[Floydian]

Fred61, your mini split one solution fits all is interesting. Can you refer me to units that can do the job in the well below 0 temps of northern MN? We may have extended periods when the temperature does not even get above 0F in the daytime, and night temps can range down to -30F and lower. I was of the understanding that an air source heat pump bottoms out on operation at something around +15-20F, but if they can operate efficiently into the below 0F range that I experience where I live, I would like to research that further. Thanks.

Jim,

Mitsubishi's Hyper Heat and Fujistu's Halcyon models can go low but for the temps you have I think they would perform well in the shoulder season then let the wood stove do the heavy lifting when those really cold temps roll in.
This is exactly how we will be heating the super insulated house I am building for my folks. Fujitsu mini split on the main level with a little Jotul in the basement. In my neck of the woods a seasonal COP of 3.5+ is realistic. I don't know about Northern MN but I'd guess something around 2.5. Hmm, Daikin also make some low temp models.

Noah

 

[Floydian]

KMR,

Will you be building this house yourself or hiring it out? Either way, it is likely well worth your while to get an energy consultant involved as there are so many aspects to building a super insulated house and having someone to make sure you or your contractor are on the right path from the get go is critical.

In some ways you are at a point where you can choose how much energy it is going to take to keep your house comfortable. Pay now or pay more later. 20 million btu's a year? 60 million btus? How much wood do you want to process? Now vs 20 yrs from now?

Build tight, ventilate right. Super insulate. Triple pane glazing. Appropriately sized, high solar heat gain(SGHC) on the south facing glass with proper overhangs, HRV, continuous air barrier, avoid complex bump outs, dormers if possible. A compact shape will give you the most square footage to the least exterior area possible.....Did I miss anything? Yep, lots.

Remember, some of the biggest advantages to super insulating are comfort, durability,healthy, low energy for the life of the building and simple mechanicals. IMO,mini splits and a wood stove in the right layout will do just fine. Radiant floors are nice......in houses with too little insulation(like mine). In a super insulated house the heated floors wont even feel warm 95% of the time and a super insulated house does not need radiant heat to achieve a high mean radiant temp-MRT. (broken link removed to http://www.healthyheating.com/Definitions/Mean%20Radiant.htm#.UgRb5pKsh8E)

Also check out http://www.greenbuildingadvisor.com/ and http://www.buildingscience.com/

OK, I am rambling. Time for bed.

Good luck with the project,

Noah

 

[willyswagon]

I couldn't agree more with Floydian. If I had a clean slate, I copy what a friend of mine did in Halifax. We talked his house over for two tears, then it took two years to build using the friend and family work force plan. ICF, great glass, super insulated, very efficient air movement, solar hot water system, wood stove as main heat source. It's a big house, and he heats it for 2.5 cords, and his wife runs it hot( like 23* C hot). Depending where in NS you could super insulate and go with a heat pump only, but if you have an endless source of wood...... Keep your plans for propane stove for cooking and if you feel you need a back up use a small propane boiler.
Time is on your side, and remember it costs about 20% more to do it right the first time, about 50% more to fix mistakes and re do it on the second attempt.

 

[Fred61]

Fred61, your mini split one solution fits all is interesting. Can you refer me to units that can do the job in the well below 0 temps of northern MN? We may have extended periods when the temperature does not even get above 0F in the daytime, and night temps can range down to -30F and lower. I was of the understanding that an air source heat pump bottoms out on operation at something around +15-20F, but if they can operate efficiently into the below 0F range that I experience where I live, I would like to research that further. Thanks.

I have a pair of mini-splits installed and they seem to become inefficient below 35 or 40 degrees but I included minis in my suggestion to the OP to cover the cooling aspect of his project as well as heating in the shoulder season during the colder nights. I haven't looked into it but I recently saw a headline somewhere that our local utility is going to be offering an air source heat pump to a limited number of customers in an experiment. Although I don't remember the numbers, I recall that they seemed impressive. Being a "news junkie" I read everything and at times other headlines take precedent.

With the right construction, a small propane boiler with radiant and a masonry stove should suffice. A wood boiler with storage installed in a properly built home would take several years to pay back. The owner could use the time he spent processing wood and maintaining a boiler on a different hobby. Perhaps one that's easier on his body when he gets into his seventies as I am. I only burn 3 cords but they are becoming more painful with each passing year.

 

[jebatty]

I'm just 66, a young guy, so CSP about 8 cords/yr, 4 for the house and 4 for the shop, are not yet very burdensome, but I can see that happening. I also see that my 3 sons/son-in law could use some physical exercise, so CSP may be on the agenda unbeknownst for them. I will keep mini splits or just an air source heat pump in mind in the future. We probably might use A/C about one week per year, so that is not a factor for us, and we now don't have A/C, just ceiling fans.

I consider fossil fuels a virus infecting human beings, so that is another reason to avoid electricity and propane. Wood for fuel from sustainably managed wood lands is carbon neutral and is also very efficient, when used with a wood gasification boiler or an efficient wood stove. We have heated with wood for more than 23 years; it is in our blood. It also comes from our land and the out of pocket cost is minimal.

 

[KMR]

I am considering ICF for the basement with some extra insulation. But the green building advisor website linked above notes "... the researchers concluded that an ICF wall offers no thermal mass benefits in Canada." The site also says that the walls have a low R value. Given this information is ICF a good option for my climate, especially considering the extra cost involved?

Wood has a certain appeal when done in a sustainable manner especially since I have an unlimited supply that I can manage myself. My building site is also in an excellent spot to leverage wind power so that is something I would like to investigate in the future. What is involved in keeping the heat going in the event of a power outage when not using electric as the primary heat source?

 

[maple1]

I consider fossil fuels a virus infecting human beings, so that is another reason to avoid electricity and propane.

I'm in the same province as the OP. Here, our electricity is shifting from fossil fueled to more renewables. Wind, hydro, tidal & biomass are all increasing. Whether it's (the shift, that is) being done 'right' or not at present is another whole political debate - but I would not class electricity as simply fossil and avoid it solely for that reason.

My wood fired boiler heating system can heat us fine when the power goes out. It runs on natural draft (no fans), and the water can circulate by gravity. If going new construction though, I'm not sure that's the most practical way to go. It is as warm & comfortable as all get-out, and fairly efficient - but I could have likely bought 10 quite nice wood stoves for what it cost us to put in. Hard to beat a modern wood stove for green simple efficient non-electric space heating.

I have read in some places that some bugs like styrofoam. I'm sure there has been a thread or two on Hearth about that, with pics. I'm not sure if that would apply to ICF and the bugs here - but I think I would go conventional concrete, well insulated on the inside at & below grade. Once above that, I'd be digesting all I could on super insulating construction techniques and thinking southern exposure. I'm way behind on new building tech now so don't have much else to offer. But mini-splits are running rampant up here - not sure what part of NS you're in, but it's generally the most moderate climate in Canada, so they seem to be proving out quite well. I'm in the most wintery part of it, aside from the Highlands.

 

[bmblank]

I would for sure go with icfs. I can understand how they wouldn't bee considered much thermal mass, what with the 3 inches of insulation between the inside and the concrete, but to say that the r value is low is crazy. 6 inches of polystyrene and 6 of concrete...
My brother has a 40 by 60 ft garage built out of them and even with an uninsulated ceiling the heat of a vehicle is enough to melt all the snow off of the vehicles. This is in northern mich.

 

[KMR]

I will leave the NS Power debate aside other than to say that it is a widely reviled company. The vast majority of our power comes from coal which is the dirtiest power available; as far as I can tell the wind and hydro projects are token gestures from a California based energy company. What happened in the California energy space when Enron was around leaves a bitter taste in my mouth for these people. I'm not sure how the energy buyback programs work at the moment but I understand they are changing which might alter my calculations given my ability to generate wind power.

Would ground source heat pumps and a wood stove for backup / comfort be a viable option and what sort of costs would I be looking at? Out of curiosity maple1 what sort of costs did you run into with your system, if you don't mind my asking?

 

[Fred61]

Masonry stoves aren't cheap but when installed in a correctly insulated home designed to take advantage of the radiating heat they will satisfy your dream of heating with wood without all the mechanics of a wood boiler system. No moving parts and no need for electricity.

 

[KMR]

I'm not making any assertions here about the insulating qualities of ICF, just noting what the referenced site said. On a side note I have heard that the energy required to produce concrete is very high. I would be interested to see some comparisons of net energy inputs for concrete vs standard building over the life of a house.

 

[jebatty]

Here, our electricity is shifting from fossil fueled to more renewables. Wind, hydro, tidal & biomass are all increasing.... - but I would not class electricity as simply fossil and avoid it solely for that reason.

My guess is that your province/electricity supplier is doing better to make the shift away from fossil fuels than is the one serving me. Our supplier, a co-op, is doing nearly everything possible to avoid and defeat any move away from coal. In the July/August newsletter from the co-op CEO, he rails against proposals to limit greenhouse gases, energy efficiency mandates, renewable energy mandates, and he argues that these will only increase costs with no benefits. I am fed up with the co-op but I have no other electric supplier. So, I am completing a plan to install solar electric which will offset most of our electricity use from the co-op.

 

[Fred61]

I've been in two different homes with ground source heat pumps and didn't find them to be very comfortable. First was the fan noise which needs to move a massive amount of air plus the sound of rushing air and secondly the low temperature of the fast moving air was cold enough to be uncomfortable. In one of the houses the air pressure was so high the return air wouldn't take all the supply and it was difficult to open the basement door because of the pressure against it.

 

[arbutus]

...

Would ground source heat pumps and a wood stove for backup / comfort be a viable option and what sort of costs would I be looking at? Out of curiosity maple1 what sort of costs did you run into with your system, if you don't mind my asking?

My friend and former neighbor ran an open loop geothermal heat pump from mid October through April. It was a 2 or 2.5 ton unit, iirc. It would keep his house at about 55 on cold winter days. He burned a large Quadrafire wood stove from November through March to supplement his heating needs, and the house was always toasty when I went to visit.

He also generated some of his own electricity, primarily with wind in the winter.

 

[KMR]

Where does DHW fit into this? Is a heat pump system that provides heating / air conditioning / and DHW cost effective? If anyone has a system like this I would be interested to know what the energy costs are. The potential benefit of wood / solar thermal is that all heating and DHW would be free, but that comes with a high upfront cost.

 

[willyswagon]

If starting fresh read this, break out a calculator, crunch the numbers, save your wood for campfires!
High upfront costs are not an issue when it is so cheap to run the home due to ultra low energy usage.
my dream build
http://www.nauglerhouse.com/

 

[Fred61]

I am considering ICF for the basement with some extra insulation. But the green building advisor website linked above notes "... the researchers concluded that an ICF wall offers no thermal mass benefits in Canada." The site also says that the walls have a low R value. Given this information is ICF a good option for my climate, especially considering the extra cost involved?

I hate to disagree because I am arguing against people with the title: researchers and I have no title. But (see what I mean, started a sentence with but) thermal mass that is not isolated from the colder and wetter outside temperatures is nothing but a conduit sending heat to cold. just like sheetrock on an outside wall that is not isolated from the studs.
In some of the colder climates (before global warming) builders needed to backfill ICF foundations with very porous material otherwise the soil would freeze all the way up to the wall and push it in. With regular poured foundations it stayed thawed about a foot from the wall. Now does that tell you something?

 

[maple1]

I will leave the NS Power debate aside other than to say that it is a widely reviled company. The vast majority of our power comes from coal which is the dirtiest power available; as far as I can tell the wind and hydro projects are token gestures from a California based energy company. What happened in the California energy space when Enron was around leaves a bitter taste in my mouth for these people. I'm not sure how the energy buyback programs work at the moment but I understand they are changing which might alter my calculations given my ability to generate wind power.

Would ground source heat pumps and a wood stove for backup / comfort be a viable option and what sort of costs would I be looking at? Out of curiosity maple1 what sort of costs did you run into with your system, if you don't mind my asking?

Yes, we could go on & on with NSP.

Costs to revise my system (most details in my linked build thread) was very close to $15k. That's everything, all in (taxes etc.). That replaced everything in my system except for the heat distribution (piping & baseboard). Also included in that is the kick I took in freight, duty & exchange in getting the boiler & its accessories here from PA, which amounted to around a $2k kick. I also did everything myself - so no labour, except for minimal for the electrician to wire up my electric boiler & hot water tank. Free fuel as long as I am able to handle the wood.

From the looking at Geothermal I did, I think you would be looking at around $20k, not including the ductwork or distribution system. They will do hot water, but I think I have heard that efficiency is not that great doing it. They likely heat better doing in floor or low temp radiant, but then you lose the A/C possibility, unless you install both piping & ducting for a mixed system. And I have heard widely varying stories on the power bill to run them.

IMO, it is hard to beat the simple efficiency of an ordinary electric hot water heater for DHW. It is nice to have it tied to a wood boiler though. I roughly figured that cost for our hot water when we switched to the new 80 gallon electric tank was right around $30/mo increase in electricity costs.

Depending on the house configuration, if I was starting from scratch, I would likely lean heavily to having mini-splits, a wood stove or two, and an electric hot water tank. I would also likely look into a pellet boiler such as the Windhager - although leery of future pellet prices & supply here. The one thing that would make all this hard for me is balancing the comfort of hydronic zoned heating (all-around the best, IMO), with the desire or need for AC in the summer.