Being new to radiant heating, I don't have any experience with installing or using a radiant system. As a result, I'm trying to get an understanding of proven designs for use in Ontario homes vs. what may be "bleeding edge" or possibly industry hype.

Based on my perception of the benefits of radiant heat, my ideal scenario for our ICF house would be to use hydronic radiant heat on both floors of the house - using the same heat source to provide our domestic hot water and heating. Also, in addition to designing the windows for passive solar gain, I would eventually like to add a solar water heating system to reduce our energy consumption. However, a complicating factor is that our city by-laws require that we also provide "central air conditioning" because we are building next to railway tracks. Finally, as with all new construction, we need to provide a heat/energy recovery ventilation system for the house.

Is it feasible - at a reasonable cost - to do all of the above?

A heating contractor we spoke to today about this concluded the discussion by recommending that we go to a high efficiency residential HVAC system and not even bother with hydronic. The heating contractor said that (from his personal experience) in-floor heating would not deliver consistent heat and trying to go all hydronic + solar was too radical/expensive to be approved locally or pay-back in a reasonable amount of time. Plus, he indicated that an Open Direct system would not pass the Ontario Building Code due to potable hot water mixing with heating water.

Has anyone implemented an Open Direct radiant system in Ontario, Canada? How is the potable water concern addressed?

With respect to the "central air conditioning" requirement, has anyone sucessfully used municipal water in a radiant system to cool their house in the summer?

An example of what I mean is here http://www.radiantec.com/systems-sources/open-summer-cooling-mode.php. The contractor told us flatly that this concept would simply not work to cool a house because tap water usage is so variable. Plus, he indicated the bathroom floors could become too cold to be comfortable.

For those homes using hydronic throughout, what are the popular ERV/HRV systems? Also, can they be implemented with less ductwork than a conventional HVAC system?

Advice, information sources and suggestions would be appreciated.

Brian.

your HRV ties into your AC ducting, easy.

Hydronics not providing consistent heat is entirely a question of design. Poor designs can have poor results.

Solar DHW is fairly reasonable. Solar Heating is not economically justifiable at this time. Maybe two weeks from now that will change, but at this time, the panel area you need to add to make it worth using for heat, at the time of year it is least effective, is UNLIKELY (possible but unlikely) to be cost effective, now.

But, you can always design a hydronic system for low temps, so you can add things like solar later when they DO make sense...

I think open direct systems are poor ideas, both for the longetivity of your heating system and for possible health concerns.

finally, "limited free cooling" this way is indeed limited. so ridiculously limited it should never be mentioned. Condensation is also a possible concern.

Hello Brian. I hope your question has been answered earlier. Hydronic cooling with open or closed loop in Southern Ontario is tricky due to our high humidity. It is being done in Western Canada and could be done here. You would have to have your ERV control excess humidity and keep your floor at he proper temp to eliminate sweating. You most likely would also have to add som fan coil cooling as the infloor radiant may not be enough at the higher floor temperatures required to prevent sweating. In the case of open loop you cold mix the water to keep the temperature high enough. Jim