Seeking Guidance on Heating Options for 1890s Farmhouse Renovation
I’m in the process of renovating a gutted 1890s farmhouse and need advice on heating options. Initially we planned to use ducted mini-splits, but we’ve heard concerns about their performance during extremely cold days and potential challenges with generator compatibility (power outages are occasional in our area).
We’re now considering hydronic baseboards but this would shift us toward relying on propane – and make furniture placement more tricky.
Our goal was to make the house primarily electric to transition to solar in the future. Additionally, if we go with hydronic baseboards, we would likely need to add ductless mini-splits for air conditioning at some point.
On the plus, side if we go with hydronic baseboards – we would get a nice Navien combi boiler with on-demand hot water.
Could you outline which option would be safer (the house is for an elderly couple), more efficient (it will be insulated mainly with Rockwool), and environmentally friendly? We keep going back and forth on this decision.
Any advice would be greatly appreciated!
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Replies
My opinion hydronic heating is a poor fit for your long-term goals.
In that fueling a hydronic distribution from an electric source leaves you with few good options. One an electric resistance boiler the are very expensive to operate. Two an air to water heat pump that is a rare emerging technology that is poorly supported and overpriced. Three ground source to water heat pump generally the install costs are so high that they never pay off.
The other problem with hydronic is that a separate cooling system is required that doubles your HVAC budget on top of the perineum price tag hydronic systems command.
I say make this a tight well insulated house with a good air to air heat pump.
The sad thing is if you made a detailed list of all your planed improvements with a budget number for each it would be less expensive to bulldoze the foundation and rebuild something that looks the same that will be more energy efficient than the retrofit ever could hope to be.
I think propane is the most expensive possible way to heat a home
Walta
“ I think propane is the most expensive possible way to heat a home”
This is very dependent on where you are located and not necessarily true. For example, in CA the cost of a gal of propane right now is 2.57. The cost of a khw is about $.36.
For a heat pump with a cop of 3, that works out to about 28353 btu/$1.
For propane, assuming .95 efficiency boiler, you get 33822 btu/$1
The worst thing about propane is that it is total unregulated by most state governments unlike natural gas, and electricity where prices are fixed by regulation. Should supply and or demand change tomorrow, the price of propane could easily exceed $7.00 a gallon again in a matter of days.
Who owns the tank also changes the price per gallon a lot. If you own the tank you can shop for the best price. If a supplier provides a “free” tank you pay whatever they chouse to charge or freeze to death.
Walta
Yes this is probably true and I don't think propane is a good long term solution to our energy needs. But until we all have solar or fusion energy is realized, It is not as bad as it gets made to be from a financial perspective. Also considering 60% of grid energy is from fossil fuels and there are aprox 30% energy loss from generation to house hold I think it is also not as bad in regard to carbon emission.
Also even if it goes to $7 a gallon it will still be cheaper than resistance electric in the above scenario as you will lose that 3 cop.
Thanks Walta. I hadn't considered either air to air or air to water. I was thinking that if we went with the hydronic baseboard, it would be propane. I'm going to look into it, appreciate the feedback.
If you took what I said as a recommendation for air to water or ground to water heat pump systems, I totally failed in my post.
Walta
I would do both. In rural areas (and really any cold climate) I think it’s worth the peace of mind to have multiple heating options in case of power failure. I have used a navien in conjunction with wall radiators and it worked great. It will definitely add upfront cost, though the combi gets you a pretty good deal considering it also does dhw. As far as the mini split goes, you could then either size it for cooling and still use it in a heating environment by just setting its thermostat higher than your hydronic so that it is basically always running and the hydronic kicks in as supplemental.
With the navien system its zone controller annoyingly does not supply 24v to the thermostats so you need to run a standard 4 wire thermostat cable and splice into a 24v transformer. They sell them specifically for this but it’s just annoying if that is not identified at time of rough in wires. Or else you can get a battery thermostat but that is annoying with today’s smart thermostats.
As far as cost to run, depending on your gas and electric cost the differential is not that great, it has more to do with reducing greenhouse gas emissions, and depending on your utility, it may be the same at the current time.
Thanks for the advice. That's a great idea, we're in the northeast so it makes sense to do both. I have a Navien combi for my radiant floor & water and it's great. The old farmhouse reno is for an elderly couple and we want to make sure that it's safe for them, environmentally responsible, but also so that they don't have to worry about losing heat during a power outage. They want to convert to solar ultimately but it would gives us peace of mind to have some backup/propane in the meantime.
You don't mention the location or climate zone, which would improve the responses quite a bit. ;)
If you are running ductwork (I'm assuming there was no original ductwork, maybe https://rheiacomfort.com/ would be helpful?), then I'd consider something like a Mitsubishi Intelliheat dual fuel air-to-air heatpump. You can use their hyperheat outdoor units (MKZ series), combined with a small gas furnace (I think these can be jetted for propane, but haven't confirmed that). They will run as a heatpump in virtually all conditions, but can light up the gas furnace in low temperatures or manually if you were running on generator. They can be set for economic cutover, which would maybe be in 30F sort of range with your quoted propane prices, or capacity cutover, which would be more in the 0F range.
That would let you heat and cool from the more efficient heatpump, but have gas/propane backup if you really deem it necessary.
They hydronic baseboards really feel like you'd be painting yourself into a corner for future options. Propane is cheap now but won't always be, and there just aren't a lot of other US options for that system now.
Good point! The build is in zone 6a, Damascus PA.
Interesting, I don't know there are dual fuel air-to-air heatpump. I'm going to dig into it a bit more but sounds like they can do aircon as well which is a bonus. The house is completely gutted so we're at a point where we can add ductwork and run anything it through the attic and crawl space.
It seems like the best option for us is to have two sources - one more sustainable (air to air, air to water, electric) as well as a secondary or backup gas/propane.
Thanks for the suggestion!
I’m currently sitting in an 1800’s farmhouse of my own. It’s -3 outside at the moment, and our mini splits are keeping things a balmy 68. I put in baseboard resistance heaters also for an emergency backup, and have only run them one time when it dropped to -23. And even then, they were only a supplement.
Sounds good, thanks!