Hey Everyone! I stumbled upon this forum while searching for some HVAC information on a new build I'm looking at starting this summer. I am hoping to pick some brains here and get some input on what might be the best ideas to maximize efficiency.

Location: Boissevain, Manitoba area. Very cold winters. Decently hot summers.

Utilities: Electric $0.07381 /kWh. Nat Gas $0.3085 /m^3

House: 1900ish sq ft raised bungalow. Full finished basement.

Logix ICF basement construction. Builder said it would just as good and much cheaper to go 2x6 wood main level with an additional strapping to push it to 8" walls. Then wiring, etc could be ran inside the strapping area so minimal vapour barrier piercings (tight envelope). Joint spaces will be spray foamed.

Looking to make this my "forever home". Wiling to pay more up front if the payback is there.

HVAC: This is where I'm very confused. Definitely want central AC for summer. Have been looking at hydro radiant in basement floor heat. Considering it for main level as well, but unsure. Other options would be heat pump (too cold for max efficiency though?) or nat gas furnace. Polaris HWT best for in floor or go with nat gas boiler? Pretty sure ground water temps are too cold to go with on demand hot water, but could always look at dual units in line to get sufficient temp rise (probably very inefficient though).

Really looking for advice on building specs as far as spend the money on ICF on main level too or no. 8" wall setup a good alternative for main level? And then the full mechanics. No clue here. Is geothermal still the best option? I've heard with a tight envelop the pay back isn't there. Plus if anything happens to equipment, the cost to repair wipes out any savings.

We will also have a 3 car garage attached. Wouldn't mind the option of heating the floor in there or having some sort of heat source on demand (probably not full time unless we go geo).

I know this is very vague, but hopefully I can get a starting point and move forward and critique from there. Thanks everyone! I really appreciate any input.

A high efficiency heat pump with a natural gas furnace as your backup heat when it gets really cold would be an option I would consider for your HVAC system since you apparently have natural gas available and relatively low electric rates. Use the heat pump when it operates most efficiently, then have it switch over to gas when the outside temperature gets below the heat pump's optimum operating temperature. Plus the heat pump also provides for summer time cooling and dehumidification. Size the heat pump for the cooling load for optimum comfort and efficiency and let the gas furnace pick up the slack when it gets really cold. This also provides you with a means of backup heat in the event the electricity is out with just a small generator to power the blower in the furnace. With this arrangement you would have a natural gas furnace with blower installed, then the heat pump "A" coil installed directly above the furnace duct outlet, with the heat pump compressor and coil outside. This is assuming an up-flow furnace/air handler would be in the basement with your duct system located in the conditioned space between the basement and main floor. Keeping the duct work in the conditioned space significantly improves system efficiency.

What kind of floor structure did you have in mind? I used open web floor trusses to allow routing of HVAC duct/water/waste/electrical through them.

Is damp sprayed cellulose insulation available in your area? If so, that option generally gives you more R value for your $ than spray foam.

As far as your garage slab goes, heating a large concrete slab doesn't lend itself to intermittent operation because it takes so long to bring that large mass of concrete up to temperature - we are talking days here rather than hours.

Thank you very much. I know someone else that built recently, but went full electric (they didn't have natural gas available at their spot). They have heat pump, furnace, boiler for basement floor radiant, plus two HWT for the house. Didn't seem like the best plan so I figured I would ask here. Still unsure on geo prices and paybacks, but I can probably find someone local to estimate costs so I can truly compare that as well.

Floor structure will definitely be open web floor trusses. I'm hoping to run everything within the spaces available so I can have full height ceilings (9" up with some additional vaulting and 9" down).

Never heard of damp sprayed cellulose. I will definitely look into it though. From what I can tell, the builder just buys those cheap (well $200ish) kits from HD and uses a couple of them to do the joist spaces as he claims its much cheaper then subbing it out. No clue.

Good call on the garage floor heating. I always tend to forget radiant is a very slow adjusting heat method. Thanks!

Why stop at main floor, go right to the rafters. Yes, ICF will be more expensive than 2x6, but, your building envelope will be MUCH tighter, vapour barrier and insulation is already done and it makes a very quiet living environment.  This is the way I went for our cottage, (retirement home) I used Silver Fox blocks R-27 along with their Fox Bucks which gives thermal breaks rather than wood bucks. 
read this thread about thermal mass  http://www.greenbuildingtalk.com/Fo...fault.aspx 
  I never thought I'd get more R value than the foam supplies, (thermal mass)  but am very happy with the performance of the building.  Take a look at my building blog http://kasshabog.blogspot.ca/  maybe it can help you answer some build questions.
  Stuart

"I always tend to forget radiant is a very slow adjusting heat method."

This is a good thing to forget, as it is irrelevant in new construction and only comes into play when older structures, we do many, are being retrofit for radiant. In such cases, response time can be factor to be considered and anticipated, but rarely is it a deciding factor in HRH design practice.

We have many thousands of home here in the Minneapolis area that use a power-vented water heater for space and domestic hot water leaving upper floors to the inferior, but always cheaper forced-air furnaces. The exception to this is the generally poor comfort and nearly always more expensive ground source heat pump.

It is all a matter of priority.

Well Minneapolis is fairly similar as far as climate is concerned... So you install full pex hydronic heating systems without any sort of back up and have no issues? I have this weird feeling in the back of my head that if I don't go full hydronic I'm going to regret it. So you do the mod con boilers and that handles full home heat plus hot water? Any suggestions as far as cooling?

We use mini-splits where appropriate and High Velocity where multi-room or levels make mini-splits impractical. We also consult on low-load construction designs considering solar loads from windows and wall assemblies.

Where the energy loads lean heavily to the space heating side like our part of the world and also San Francisco, interestingly enough, the focus should be on heating without the unmistakable compromise all forced air systems represent.
Your near-neighbor Winnipeg, for example, averaged 5,777 heating degree days per year, compared to 186 cooling degree days, from 1971 to 2000, according to data from Environment Canada: http://www.ccme.ca/assets/pdf/cind_people_htng_clng_e.pdf.
It makes little sense to focus on cooling when the weighted load is so far to the heating side. It would be cheaper to summer in Yellow Knife than spring for expensive AC like a mini-split for the few weeks you will need it up nort der, eh?

A proper heat load analysis will tell you the real truth of it. And forget the DIY heat loads. This is an area where proper tools, an ACCA Manual 'J' and relevant experience matter. Find people who design and build more than one kind of house, in more than one climate zone if you can.

“Looking to make this my ‘forever home’. Willing to pay more up front if the payback is there.”

Yes, with regard to payback, money is nearly always best spent on improving the building envelope (i.e., insulation and sealing) and creating a low load, energy efficient home. Once you achieve that, it will be a comfortable home no matter how you actually heat it and the question then becomes how many thousands of dollars do you really want to spend on a HVAC system just to provide a couple hundred dollars of annual heat?

There is no question that hydronic radiant floor heating can be a comfortable heating option...likely the best. If you are pouring a slab, it almost always makes good ROI sense to put a couple hundred dollars of PEX in the slab and use it as a hydronic radiant floor heating system. A slab that is not finished with insulation material is also the most efficient floor hydronic emitter so your operational performace will be good too.  However, if you are not pouring a slab, the ROI quickly becomes problematic and the operational performance becomes less than good.

A heat pump HVAC system can’t really be beat in terms of good operational performance and associated low operational cost. However, if this will be a low-load, energy efficient building, a hydronic radiant floor heating system may not be perceived to be as comfortable as one might expect. A hydronic radiant floor typically feels “barefoot comfortable” to most people when the floor temp is between 80-85F. For a low-load, energy efficient building, the floor temp may never exceed 75F. So while the floor won’t feel cold, it likely will NOT feel “barefoot comfortable” as one might expect.

Find good people who work in your location and carefully check their credentials. There will be no shortage of people trying to get the dollars in your wallet into their wallet, LOL!

Good to know. I'll get some prices on the various HVAC systems and go from there.

In regards to making the envelope as tight as possible.. Would ICF all the way up be the best idea or use the money for sprayed, continuous exterior insulation? What is the best way to go?

Also, any reallllllly good exterior doors out there? Any door I've seen has always had leaks or poor R value, etc.

ICF…funny you should ask… Perhaps read this thread when you have lots of time as you will need to get to the final conclusion, LOL!

ICF Effective R-value Discussion & Software Program

We love ICF, but be careful about your effective R-value expectations…there is much exaggeration and hype… It would appear that ICF does indeed have a significantly higher effective R-value than the conventional R-value in warm/hot diurnal temp climates because of thermal mass effect. However, it would also appear that ICF doesn’t perform nearly as well in colder climates. Of course, using ICF should result in much lower outside air infiltration than could be easily obtained using other construction techniques. Infiltration is typically the biggest factor for undesirable building heat gain/loss so minimizing infiltration goes a long way in achieving an energy efficient building. You will likely get lots of opinions about ICF versus other construction methods.

Doors...you will get lots of opinions about doors and windows too... Perhaps research what has already been discussed in the door/window forum section and perhaps start a separate thread too.

HiQ
ICF all the way would definitely be best. We live in an ICF house outside Calgary Alberta and can tell you that our house out performs R50 in the winter with next to no diurnal swings.
In conversation with family members in Manitoba, for some reason there does not seem to be much competition for the ICF market there and as a result the numbers are higher then what they are here in Alberta so you need to check numbers.

Any building model that stops the cold before it enters the wall assembly will perform better then one that stops it in the wall. Using eps on the outside rather then strapping a frame construction on the inside will make more cents.

It is hard to beat radiant heat for comfort but if you go with ICF envelope the roi for a high end heating system may not be there. You have much higher prolonged heat days in much of Manitoba then we do here in the Calgary area so I understand your desire for AC but remember the good building envelope also keeps the home cooler. It is the need for ac that make geo somewhat doable in your area where it is not worth while in ours.

Hm.. Okay so time to price out the different building envelope costs and then take a hard look at whether we need to spend bank on the high end heat.

Another thing I'm looking to avoid is drops in the basement ceiling. With the open web floor trusses I'm hoping we can engineer them to accept the trunks. I want full height in the basement. Not sure why, but I very much dislike the drop that everyone has along the main section of their basement. Obviously full radiant would fix that issue or high velocity (ability to put flex ducting almost anywhere).

Yup, open web floor trusses are the way to go, keep all mechanicals up so there is no boxing around them. I have full 8' ceilings, plus with the ICF you can hang your floor truss ledger off it with Simpson ICF hangers so there is no thermal breaks.  Don't forget  you'll need to run ducting for your returns too, that or a lot of panning.

ICF is not only thermally superior, but also very quiet, like radiant heating.

If you opt for the uncompromising comfort of radiant heat and have a superior envelope, i.e. low heating loads, you should consider a combi-water heating/radiant floor system with AC as an entirely different system, since the requirements of heating and cooling (mostly a function of latent heat) are not related.

I am waiting for an affordable enhanced ERV that will actively de-humidify.

First, as always, you must have an ACCA Manual 'J' heat/cool load to intelligently weigh your options.

HiQ,
Make the envelope as efficient as possible. Incorporate high exposed internal thermal mass. ICFs build a great house but manufacturers charge to much for their block and ties systems. I am an engineer, and designed a DIY ICF system that delivered twice the foam insulation for the same cost as available products at the last build we did.

You have a fairly low deep earth temperature. If you decide on AC a simple earth tube and fan with balanced thermal mass would be plenty. Less than 1/20 the operating cost and no compressor to replace every 10 years. No additional up front costs.

Tell me if you want to no more.

Changing the world one building at a time.

Solar thermal heating with an insulated reservoir works in your climate.