Freezing Pipes, Conventional Houses, and Wood/Mass Heaters

Hi Folks, this is a spin-off from this thread: https://permies.com/t/197678/sour-grapes-snake-oil-corporate .

Some of us were mulling (OT) the problem of wood stove/RMH's as the sole heat source in conventional design houses, and whether that was ultimately practical.

Anyway, the question arose: IF we were using wood stoves/RMH's exclusively, could we go away for more than a day and be confident that the pipes would not freeze?

Personally, I think it's a home design issue, with water supply piping installed inches from the exterior foundation and other nonsense, all of which is baked in with the assumption of electricity and natural gas on demand. That's my 1975 house, and I see a lot of similar stuff even now.

Your thoughts? Ideas for solutions?

I bought a conventional house in London Ontario (ie "snow belt") in the late 1980's. I specifically looked for one with as little piping on outside walls, and I had never heard of an RMH (or permaculture) at the time, but I was aware of energy conservation.

If I knew then, what I know now:
1.  I would have had shut-off valves for the sinks located in places where genuinely draining the water - and knowing it was drained - would be easy.
2. Since off grid wouldn't have been an option in that situation anyway, I'd have considered also having key pipes wrapped in the electrical heat-wrap tape. I don't know if that stuff is available for use with 12 volts, but that would be even better if "interrupted power" is high risk.
3. I had at least already figured out that the furnace wouldn't work without electricity even though it was gas. However, I had not paid extra for a fireplace, because I knew that modern fireplaces were totally inefficient. I was just a little late in understanding that week-long electrical outages could happen to city-dwelling me! Even though it was a new house that was well insulated, it would need to have some plumbing work done - nothing outside my ability with a little talking to people who'd done it before.

Alas, before that awakening, I got married, sold that house and moved to Ottawa, Ontario, then moved again to BC. Current house has *way* too many pipes that are difficult to shut off on outside walls because "it never gets cold here" - yeah, right, except when it does!!! We've got plenty of big trees to come down just when we *need* that heating the most.

So, yes this is a good thread for brain-storming options and the things permies might consider spending money on "upgrading".

Lots of folks have seasonal cabins, and at the end of the day they blow out the lines with compressed air. The lines can't freeze (expand) and cause damage.

That could work with conventional houses too, if they had a draindown point. That is, if the water pipes were sloped to drain by gravity to a low  point, where a tap would allow the water to drain.

When I think about this old farmhouse, the indoor plumbing is both great benefit and Achilles' Heel.  Unlike the original owners, I no longer have to navigate snowdrifts in the middle of a chilly -20F night to find the outhouse, perched as it was over the riverbank... (!!..thems were the days, yes?).  And yet without the vulnerability of a network of plumbing, those same owners could have installed an RMH with excellent effect.  It likely would have outperformed their central main-floor woodstove and would have heated the upstairs through the same registers the old house had back then (and still has).  The root cellar was snugly nestled below the SE side of the house with hay bales added to the exterior cellar doors for good measure.

With the plumbing down there, greater creativity is needed to ensure their function through even single deep-cold nights.  I was intrigued by dual-fuel furnaces for that reason (wood + oil, wood + propane, etc...) but am not sure about insurance and availability at this point....nor whether electricity is needed when running on wood exclusively.  At any rate, I've come to realize that an RMH in a conventional home *is* possible, but with some extra forethought as to how to deal with these types of contingencies.

Douglas Alpenstock wrote:Lots of folks have seasonal cabins, and at the end of the day they blow out the lines with compressed air. The lines can't freeze (expand) and cause damage. That could work with conventional houses too, if they had a draindown point. That is, if the water pipes were sloped to drain by gravity to a low  point, where a tap would allow the water to drain.

You don't even have to blow them out so long as they're sloped in such a way that water can't pool anywhere that it would fill the pipe. If a horizontal pipe is 1/3 full of water, even it it freezes, it won't burst the pipe, because there's lots of space for the water to expand into while freezing. That said, the next time you go, if there's ice in the pipes, you may get ice dams which could be a drag if you were wanting to use the cabin for a winter weekend. People may also feel that it's best to err on the safe side.

Having the sink traps screw on rather than glued is critical so you can empty the water out of them, although so long as they aren't full, I doubt they're a big risk, because again the water has a place to creep to as it freezes.

Toilets are another matter - in Japan, my host family had a cottage in the mountains with a flush toilet. They had to work really hard to get the water out of it. I didn't get an explanation, but it may be that it was cold enough there that even the pipes underground could freeze. I was just a teen then, and my Japanese may not have been good enough to understand their explanation even if I'd asked for it.

As someone who has spent a great deal of my building career working on high efficiency houses the idea of cold spots, drafts, frozen pipes within a day sounds like a different century. For some reason though they are still being built. I've always tried to build for the energy cost I imagine will be common twenty years from now not today. It has served me well. Regardless of heating choices your home should stay warm for a prolonged period regardless of climate.

I designed my house in the early '80s fresh out of architecture school, and planned for superinsulation and some passive solar features (not full technical passive solar). Even though I eventually learned that big fiberglass-filled cavities were amazing wildlife habitat, to the point where there is/was no more insulation in some large areas of some walls and ceilings (since rectified in some areas, work ongoing), my house never freezes inside even if I am away for several days when it gets to -10 F. The kitchen sink supply piping on the south wall used to freeze if not kept trickling at zeroish or below until I found a gap in the sheathing where an addition was planned for. That has not happened since I patched that gap.

Plastic pipe is so cheap and easy that architects and designers have zero regard for efficient pipe placement.

Old houses back when pipe was threaded iron and a lot of work would place the bathroom next to the kitchen. I helped a friend rehab an older home and it had maybe twenty feet of water pipe in the house. And it wasn’t a small house.

You can build a basement/crawlspace thermal well to keep the core of the water system from freezing. They make flexible rubber P traps you can use to let sink drains freeze.

Flush Toilets have ceramic traps so they will break if the water freezes.  I don’t know a good solution other than not using a flush toilet. I suppose RV antifreeze, windshield washer fluid, or rubbing alcohol would get you a fair bit of protection.  RV antifreeze and washer fluid both cause the ice to not form a block, but form a slushy that still moves and won’t break pipes.

Hi Douglas,

As you stated, it may largely be a home design issue.   I knew a couple in MN who constructed a log cabin (not a kit) on a significant concrete pad.   It was heated with a conventional wood stove.   At 40 below F, they could leave for a week an return to a home still above freezing. Of course, it would take them a week to get all of that mass heated back up.

I built a cabin with plumbing in northern WI a decade ago.  The plumbing wasn't excessively designed for easy winterizing (blowing out) but I had the plumber do a few things.  With some work, I could get it ready for freezing in about 45 minutes.  I did that every weekend for several winters so it was a reliable solution.  Here were the details:

Cabin was off the ground with an insulated floor.  Well pipe ran up into the house inside a 4" pvc pipe with pipe tape and pipe insulation around it.  The plumber illegally? put a drain back at the well so I could drain water back to the well and below the frost line.  Alternate solution would be a "curb stop" style valve along the supply piping run below the frost line that could drain the supply line down to a bit of gravel.

I installed a 5 gallon air compressor in the attic and plumbed it to the utility closet where the water came into the cabin.  I'd shut off the water pump, drain down the pressure tank, then engage the air compressor and blow out each faucet.  If I was smart enough to have each water line as a "home run", that process would've been much faster.  I'd blow them out till they were just shooting mist.  Then I'd flush the toilets to empty the tanks and get the bowls as low as possible.  Then put some RV antifreeze in the tanks and the bowls and all P traps in the cabin.  Usually took around a gallon to do a toilet and three P traps.  Even after -20F the traps wouldn't be frozen.  You don't want to drain the toilet fully (or empty P traps) or you'll get sewage gasses up into the house!

Also, since the cabin was off the ground, I was worried about the shower P trap freezing in between uses.  So I boxed that area in with some polyiso insulation and put 2 50W light bulbs down near the p trap.  I had a light switch in the utility closet that would turn on those light bulbs and turn on the heat tape for the water supply line.  The bulbs lit up the drain so when showering you'd see the illuminated drain and know if the bulbs had burned out.

With this level of advanced thought (or retrofitting), it's pretty easy to drain down a simple house for long winter trips.  More complex systems would require more thought (washing machine, ice maker in fridge, dish washer, etc).

Going back to the idea of woodheat, RMH and freezing climates.

I'm going to assume that the house will have a human in it for about 12 hours a day - usually the coldest time of the day (night).  

When I lived in places that froze in the fall and thawed in the spring, we only ever had wood heat (although there was the backup of electric portable heaters if ever something went wrong with the fire - but it never did).  It was either fireplace or a wood furnace.  Although thinking back, the human at-home time would be more like 10 hours out of 24 and several hours of that would be spent outside, let's pretend it's 12 hours.  The other homes I knew also used wood heat.  Most of these homes were well over 100 years old.

Most of the houses had a fire on around dinner time (some of them cooked on these) and again at breakfast.  If the house was cold-soaked - aka, the walls radiated cold, we would keep the fire going all day or night depending on when we were home.

Common elements in these houses were

- plumbing zones.  We had the central core to feed the kitchens and bathrooms - usually all on the same wall so they share the same drain, but some houses were larger so there would be several main drains/walls.  The rest of the plumbing could be shut off and had a special faucet at the top and bottom of the zone that we would open to let gravity drain the zone.  These were zones with faucets on the outside of the houses.  
- insulation to fit the climate - this is the first thing we improve with every house we've lived in.  Easy to do and saves money in the summer and winter no matter what the fuel.  I'm going to assume everyone is already doing this - and if it's a rental that doesn't allow improvements, then a RMH isn't likely a possibility anyway.
- taking advantage of the sun to help heat the house - using window coverings to the fullest to insulate because windows were always the biggest heat loss in the homes I lived in, but it also meant the sun could heat up the house quickly if we let it in.
-  The house itself has a lot of mass so the goal is to start up the furnace or fire before the weather turns cold and the house loses the heat.   In places that had an underground basement, we would do what we could to get the summer heat into the cement foundations (fans to push hot air downstairs) as this has a tremendous help at keeping the house warm in winter.
- Adding mass to the heat source.  Again, we do this no matter what heat we have.  Wherever there's heat loss, I try to see if it can be captured and stored.  Extra fire bricks in the fireplace.  Cast iron kettle full of water on the woodstove (also helps increase moisture to off set the drying effects of the fire).  That sort of thing.  Storing extra bricks where the furnace room used to be.  

In Ontario, the masonry stoves were my favourite.  The one guy with the three-story house, had one in his basement and he would fire it up maybe once every three days, every other day if it got really cold.  When it was installed it weighed a few tonne so it had to be in the basement but he didn't need any other heat source because it was so good at keeping the heat from the fire.

I'm guessing this is the big advantage of the Rocket Mass Heater - the ability of the mass to gather and trap warmth to release it slowly over several days.  

I guess I've just never found using wood heat as the primary heat to be a bother or inconvenience either where I live now or when I lived where it was cold enough to freeze all winter long.  I don't know if RMH would be a lot easier as I've never tried one.

r ranson wrote:Common elements in these houses were

- plumbing zones.  We had the central core to feed the kitchens and bathrooms - usually all on the same wall so they share the same drain, but some houses were larger so there would be several main drains/walls.  The rest of the plumbing could be shut off and had a special faucet at the top and bottom of the zone that we would open to let gravity drain the zone.

Yes!! This is exactly how houses should be set up.

Douglas Alpenstock wrote:

r ranson wrote:Common elements in these houses were

- plumbing zones.  We had the central core to feed the kitchens and bathrooms - usually all on the same wall so they share the same drain, but some houses were larger so there would be several main drains/walls.  The rest of the plumbing could be shut off and had a special faucet at the top and bottom of the zone that we would open to let gravity drain the zone.

Yes!! This is exactly how houses should be set up.

Yeah, maybe it's due to cost or some other design factor, but it seems strange that indoor plumbing in personal abodes has been in practice for many decades now and yet there is the propensity to run plumbing along the inside of exterior walls.  We have few problems with main floor freeze-ups and most of the issues stem from small to not-so-small foundations cracks or breeches that allow cold air to pour into the basement.  Some of these are readily resolved whereas others are more a consequence unshared priorities in a house with multiple inhabitants. Irrespective, so much could be solved by more sensible and creative routing of pipes/PEX to their destinations away from exterior walls.  Just to add some thoughts of how we may combat the problems during power outage would be to use a propane/kerosene-based indoor safe heater for the basement for just those times.  When the power is on, we continue to use electric space heaters placed in strategic zones of the space.  But for those contemplating a new build, if you are planning a basement in an extremely cold region,  there are great design ideas in this thread to take to heart.

We just installed a wood stove and so far so good. But we have a propane fueled boiler in the basement and water pipes/radiators along the baseboards all around the house. The wood stove is in the center of the house near the thermostat for the boiler. So, as long as we have a fire burning the boiler will never kick on. Seems fine for now but I’m getting a little worried about when its -20 or colder this winter. I worry that the stove will prevent the boiler from turning on and without those baseboards warm our water lines may freeze or the basement might get too cold.

One friend in a similar situation had a second thermostat installed near her boiler in the basement and a switch to turn it off or on. So, in very cold weather she can turn off the upstairs thermostat, turn on the basement one and then her boiler will run when the basement is cold instead of when the upstairs is cold. We might look into doing the same. My only other ideas are to stop using the wood stove in the coldest weather and rely on propane instead because it will heat the basement more and all our water pipes.

So far we haven’t been using any propane, but the wood stove is burning most of the time and the weather really hasn’t been too cold. Just 20s and 30s (above zero).

I never understood this thing of putting the thermostat next to the heat source.

Thankfully they aren't difficult to move.   We put ours in the coldest part of the room in this current house.  Thankfully the geothermal heat pump has a noisy fan for the main section of the house. We set it to 65F and if the fan comes on, I know it's time to light the fire and save some money.

Brody, you could always measure the temp in the water lines when it hits 0F, -10F, -20F to see how cold they're actually getting.  Then you'll have a bit of advanced warning in time to act.  Remembering that a week of -20 will penetrate the basement more than one cold night.

Brody Ekberg wrote:
.... I’m getting a little worried about when its -20 or colder this winter. I worry that the stove will prevent the boiler from turning on and without those baseboards warm our water lines may freeze or the basement might get too cold.

Yeah, it's with a bit of irony that we run our woodstove (main floor) the most when the temps are between 0 and 30F, but actually cut back when it's below 0.  This is because the woodstove heat, even if not near the main floor thermostat, will keep that thermostat from calling for the (propane) furnace to kick on.  We need that furnace to work a bit of overtime in order to keep the basement a bit warmer during the really cold nights.

Truthfully, we have a pretty reliable coop for our electricity and the super cold weather is usually NOT accompanied by power outages.  For this reason, I'm considering installing in the basement one of those 240V ceiling mount electrical heaters that I could manually turn on just for those cold periods.  They are pretty inexpensive and easy to install, if not the most Permie option :-/

Mike Haasl wrote:Brody, you could always measure the temp in the water lines when it hits 0F, -10F, -20F to see how cold they're actually getting.  Then you'll have a bit of advanced warning in time to act.  Remembering that a week of -20 will penetrate the basement more than one cold night.

Wha...!!!?.... Mike, is there a pipe monitoring device with an alarm that would sound when the temperature reached certain level??  I would consider this as there are only 2-3 critical pipes for us that typically freeze up.

John Weiland wrote:Wha...!!!?.... Mike, is there a pipe monitoring device with an alarm that would sound when the temperature reached certain level??  I would consider this as there are only 2-3 critical pipes for us that typically freeze up.

The fastest thing I could find is a Inkbird temperature controller that measures temp with a probe and enables an outlet if it gets cold enough.  That outlet could run a heater or turn on something that would alert you (radio, etc).  I'm guessing there are simpler devices out there as well.

I actually mean that you could run the water at a nearby sink and physically measure the temperature with a thermometer.  Or set a thermometer on the water pipe to see how cold it is in that specific area.

Mike Haasl wrote:The fastest thing I could find is an Inkbird temperature controller that measures temp with a probe and enables an outlet if it gets cold enough.  That outlet could run a heater or turn on something that would alert you (radio, etc).  I'm guessing there are simpler devices out there as well.

Hubby built something like that from a kit about 40 years ago - so it's not new tech. We've used it to control the temperature in a small freezer to keep it at fridge temps to cool a friend's deer, we use it regularly to manage temperatures in our brooder room, and many wood stoves that have an integral fan have a similar feature incorporated - if the temp on the side of the wood stove is above the set point, the fan comes on. If the wood stove gets too cool, the fans automatically turn off. Its the same concept, just a variation of a theme.

Mike Haasl wrote:Brody, you could always measure the temp in the water lines when it hits 0F, -10F, -20F to see how cold they're actually getting.  Then you'll have a bit of advanced warning in time to act.  Remembering that a week of -20 will penetrate the basement more than one cold night.

Do you mean measure the temp by like filling a glass with cold water and checking the temperature?

Im also going to stuff insulation in the basement windows because they all are very leaky. Probably going to replace all the insulation around the foundation as well.

r ranson wrote:I never understood this thing of putting the thermostat next to the heat source.

Thankfully they aren't difficult to move.   We put ours in the coldest part of the room in this current house.  Thankfully the geothermal heat pump has a noisy fan for the main section of the house. We set it to 65F and if the fan comes on, I know it's time to light the fire and save some money.

Well before we installed the stove the thermostat was nowhere near our heat source. But now the wood stove is close enough to the boiler thermostat that it will never get cold enough to fire up unless we stop using the stove. Or move the thermostat

John Weiland wrote:

Yeah, it's with a bit of irony that we run our woodstove (main floor) the most when the temps are between 0 and 30F, but actually cut back when it's below 0.  This is because the woodstove heat, even if not near the main floor thermostat, will keep that thermostat from calling for the (propane) furnace to kick on.  We need that furnace to work a bit of overtime in order to keep the basement a bit warmer during the really cold nights.

I feel that irony! Even if we end up needing to do the same, the amount of money we save in spring, fall and mild winter weather would still make the wood stove worth it. We’ve only used 3% of our propane tank in the last month.

Do you need the basement warm because of the possibility of freezing pipes or just for comfort reasons?

Brody Ekberg wrote:
Do you need the basement warm because of the possibility of freezing pipes or just for comfort reasons?

Pipes freezing.  We don't use the basement for anything but storage and appliances like furnace, hot water heater, etc.

For those with a forced air furnace, the fan can be set to run continuously without the burner kicking in. Yes, it uses a bit of electricity but it's a way of circulating your wood heat and keeping cool spaces from freezing.

Brody Ekberg wrote:

Mike Haasl wrote:Brody, you could always measure the temp in the water lines

Do you mean measure the temp by like filling a glass with cold water and checking the temperature?

Yup!  Or just run the tap water over the thermometer.

John Weiland wrote:

Brody Ekberg wrote:
Do you need the basement warm because of the possibility of freezing pipes or just for comfort reasons?

Pipes freezing.  We don't use the basement for anything but storage and appliances like furnace, hot water heater, etc.

Interesting! I hope we can get away with just wood heat for most of the winter. But its down to 13 degrees and windy now and the boiler was kicking on once in a while yesterday even while burning wood. And we let the stove burn out once a week or so to clean ashes out and that gives the boiler a chance to heat the whole house up evenly for a bit.

We are lucky  for the most part; our water lines are along a center wall that is between the main bathroom and the kitchen, inner wall, so them freezing isn't an issue; even when we had the February extreme hard freeze a couple of years ago here in Texas a few years ago, we had opened the  faucets and set the faucets to trickle  water so it would keep on moving; the pipes being in a central location helped a lot.

HOWEVER, sometime during the life of this home, there was a bathroom installed in what used to be the garage; and THOSE pipes are on the outside wall in a u-shaped entry way and are not insulated very well, if at all; I think the work was done without permits, because the building inspector would have had them re-do a few things. We have to trickle the water when it gets down to below 34 degrees, and open the one cabinet door to the sink so it stays warm enough to not freeze, and if its really cold, we plug in a small space heater on low to help the space stay warm enough to avoid freezing.  

The space between the house and garage was enclosed to do a ;breezeway' type of enclosure, but there are no windows and just the back /side door.  This is not to scale, and I hope it doesn't get weird when posting  it, but this gives you the idea:

---------------------------                              ----------------------------------
main house area    |                            |X exterior wall water line for half bath; this line will freeze as during the winter it stays in shade and does not get hit by
                                |                            |        any sunshine during that time of year
                                |                            |
                                |-----\     ------------| rest of the space is my office/crafting/storage area
                                           ^
                                 Back/side Door
                                 in rear entry way

                                                                          and the door is put in there, instead of out into the back yard; as you can see, there is an area beyond the back entry way that extends to the exterior sides of the house and garage,  that really needed to have been extended to the front of the side of the house at the time; a project I am planning on f doing within the next 10 years, because I need the space for a canning kitchen/extra food storage/partial greenhouse spot. The only other sizeable opening  in the garage is a large 4 by 5 foot old thermal pane window that should have actually been made into a back door into the back yard. That's also on the list to do. We will work with what we have until it gets tot he point of us having the money to get the rest done.

Douglas said, "Anyway, the question arose: IF we were using wood stoves/RMH's exclusively, could we go away for more than a day and be confident that the pipes would not freeze?

Douglas, have you gotten an answer to your original question?

I have been trying to keep up with this thread as this is something I am interested in knowing.

I would not want to leave my home unattended with a fire going even though I would be confident to leave a furnace on low to keep pipes from freezing.

I am sorry if I miss the answer though to me the conversation has strayed away from the discussion of Rocket Mass Heaters.

Anne Miller wrote:Douglas, have you gotten an answer to your original question?

Thanks, Anne. The question is rhetorical -- I didn't expect a definitive answer because there isn't one. It's all about gaining  perspective on the design barriers that are baked into modern, conventional houses and considering the practical workarounds or retrofits. Lots of great posts!

We went away for 7 days and the temp got to -5 while we were gone. We do have a basement, which obviously helps as that is where our plumbing is. Anyway, the house was 40 degrees when we got home and nothing was frozen.

My 1886 farmhouse (updated sometime 30 years ago) has the bathroom next to the kitchen and the plumbing in the root cellar. Also the electric well pump is in there (sadly no longer in service until I have time/energy/money/solar to supply power). Was originally heated by wood / coal fired Kachelöfen (a kind of thermal mass) and the ground floor is inslated by a foot thick (low!) clay ceiling. Upper floor not really used back then ? maybe hay loft, there is a hatch high in the wall....

Of course they ruined it by oil-fired central heating with radiators and the pipes concreted in under the floor (on earth!). We have double figures minus predicted in the next weeks and the heater timer / thermostat doesn't work (busted mixer valve between rad and hot water tank side...grrr). I heard a rumour I would have to replace this boiler next year when it turns 30, not sure what I should do  - RMH out of the question - this is Germany!!!

In Ontario, the masonry stoves were my favourite.  The one guy with the three-story house, had one in his basement and he would fire it up maybe once every three days, every other day if it got really cold.  When it was installed it weighed a few tonne so it had to be in the basement but he didn't need any other heat source because it was so good at keeping the heat from the fire.

Heating and home design has changed so drastically over the last 100 years that we are at a disadvantage trying to use something like the RMH. Back then, houses were built around the heating, so a big coal, wood or oil furnace was often in the middle of the basement, maybe with a mass of brick chimney going up the center of the house. Common sense. Heat radiated out, and was stored in the center mass. Warm air rose to the upper floors. Now it doesn't matter where the (relatively small) furnace is, because heat is carried in pipes or ducting to wherever it's needed. Houses sprawl out, instead of being squarish. There's little thought to thermal mass, heated slabs being the exception (and the best way to build in cold places).
The factors that matter all come into play- how well is the house insulated (main consideration)? Where is the plumbing? Pipes on exterior walls, but inside of the insulation, won't freeze as quickly, perhaps not even for days, if you have the other factor which is mass storing the heat, regardless of where it comes from.
Having no RMH experience, I have no idea how long one could keep a house from freezing up, but as already mentioned, there's too many variables to really make any factual statements. I would not consider building an RMH without first pouring a heated slab, and running the coil through the RMH. I believe the slab coupled with the RMH would be the absolute most efficient you could get outside of passive solar. And NOW- if the house is well insulated- you can leave for a week at below zero temperatures and not worry.

I'll offer up my experience for what it's worth.  I do heat almost exclusively with a RMH and have for the past 4 winters.  My home is an old 1968 mobile home which I have retrofitted to be much better insulated.  I'd have no qualms at all about leaving for a day or two without burning a fire.  Often enough I am gone all day so the timing works out that there is no burn for 24 or more hours.  It does take a while for the mass to shed all it's heat.  Not just the mass of the RMH but the mass of the house.  I also notice that as the temp drops lower it tends to take longer and longer to drop further.  This make sense to me since the temperature differentials will be less as it gets colder.

That said, I do have the propane furnace intended as the sole heating unit for this trailer.  I keep it as back up.  For all intents and purposes it only runs when I'm away in the winter for a week or more, and then I have the thermostat on the lowest setting with the main goal being to not let the pipes freeze.

Again, I should also note that this is a mobile home, and a standard feature of mobile home life in my region is having heat tapes installed on the pipes feeding up from the ground into the trailer.  I also have them on pipes out in the unheated well house.  They have their own thermostat and should then turn on to gently heat the pipes when it gets cold enough, shutting off once the pipes are warm enough again.

I've never had an issue with frozen pipes in the house so far, including my years just using the RMH.  Where I would have frozen pipe issues was out at the well house.  The worst was when it froze and burst down in the ground!  I've since rebuilt that structure so instead of being just a thin metal shed it's a fully insulated building.  I also added insulation and another foot of dirt over the zone where the inground pipe froze.  So far so good.

Still if I was home and it is going to be super cold for many days in a row, as in negative degrees F, I will probably be tempted to leave the water running just a little bit.

I had a total remodel of the home I purchased in 2003 in East Central Indiana. I had copper pipes installed and wrapped with the heavier molded foam insulation OVER heat tapes. I don't know if the tapes are actually working or not and no way of checking unless I get someone to crawl in under the house to check it out. I turn these on the first time the temp gets down into the mid-20's

I've had ONE only freeze up and that was at the kitchen sink. I just opened the cabinet doors cleaned out all of the junk under there and set a portable ceramic heater to blow into the cabinet. It took about 45 minutes for the water to start flowing. What was my PROBLEM? An old stray male cat had actually pulled a foundation grate off and just by coincidence we had a really strong, very cold wind from the North shooting right into that hole toward the riser portion of the copper tubing that the dudes who did the work didn't wrap those riser pipes.

I have seen houses around here, and one of my rentals where the water lines are just laid on the Earth under the house, however, owners need to close up their foundation vents during the winter months to keep the air flow cut so it won't freeze the pipes. As long as there is no air flow they seem to be O.K. and last year we had some really cold weather in 2-3 week long spells.

If you just want to be able to be gone from home for a few days or so, and you don't want to fill your drain traps with anti-freeze or other toxic gunk, plain ol' 80 proof or higher booze can be poured into the drain to displace most of the water.  No taking anything apart or trying to blow air through.  Same with toilet bowls.  80 proof alcohol has an approx. freezing temp of -17 degrees F.  So mixed with a bit of water left in a drain trap it might not protect quite that low, but still WAYYY better than 32 degrees F!  Just keep a few bottles of super cheap vodka or whatever on hand and you'll only be putting food-safe liquids down into your septic tank and field.  (A caveat is that long term exposure to alcohol may affect PVC plastics, so if anyone plans to use this method long term, do your due diligence on your plumbing system vs. your alcohol type vs. how much water would be mixed with the alcohol in the traps.)  I'm not an auto person, but don't they make little squeeze-bulb tubes with different colored plastic balls inside that float or sink at different dilutions of anti-freeze?  Could that kind of thing be used or re-imagined for use with alcohol/water solutions to tell what temp it would freeze at?  That way you could test each trap to be sure you have enough alcohol in it for the temps you are expecting during your absence, at least until you get the hang of how much to pour down each drain or toilet bowl.  

For supply lines, I would install one or more drain valves at low point(s) and open a faucet at a high point(s) and just drain out as much as possible into a bucket which can be used to water plants or whatever.  

If you do a search on freezing points of natural liquids, and check out more than just the top few, you may even find something that would work better than cheap booze!  I keep Costco bottles of vodka onhand for herbal tincturing, and they are fairly cheap.  So if I had to winterize temporarily I would not hesitate to use that to protect a toilet or drain traps from freezing temps.  We have both PVC and cast iron drain lines and standard porcelain toilets.  Copper supply lines that can be drained down to the basement.  But we do not have frequent needs to be gone for days at a time in winter.

If anyone knows of any reason NOT to use vodka (or other cheap booze 80 proof or higher) for this purpose, please share!

Julie Reed wrote:Heating and home design has changed so drastically over the last 100 years that we are at a disadvantage trying to use something like the RMH. Back then, houses were built around the heating, so a big coal, wood or oil furnace was often in the middle of the basement, maybe with a mass of brick chimney going up the center of the house. Common sense. Heat radiated out, and was stored in the center mass. Warm air rose to the upper floors. Now it doesn't matter where the (relatively small) furnace is, because heat is carried in pipes or ducting to wherever it's needed. Houses sprawl out, instead of being squarish. There's little thought to thermal mass, heated slabs being the exception (and the best way to build in cold places).

Very true! Good observation, Julie.

Donna Lynn wrote:If anyone knows of any reason NOT to use vodka (or other cheap booze 80 proof or higher) for this purpose, please share!

Personally, I wouldn't use vodka for a number of reasons:
- dilution with the trap water will substantially raise the freezing point
- the alcohol can start to evaporate off, reducing protection
- it's potentially toxic to the organisms in my septic tank.

Aside from that, alcohol in my part of the world is heavily taxed. For me, it would be the most expensive option I can imagine.

Douglas Alpenstock wrote:Personally, I wouldn't use vodka for a number of reasons:
- dilution with the trap water will substantially raise the freezing point
- the alcohol can start to evaporate off, reducing protection
- it's potentially toxic to the organisms in my septic tank.

Aside from that, alcohol in my part of the world is heavily taxed. For me, it would be the most expensive option I can imagine.

I've never bought alcohol outside the US, so was blissfully unaware of it being heavily taxed in other countries.  That would absolutely make this idea a non-starter!

As for the dilution, a plunger easily and quickly removes much of the water left in a trap, so unless you expect temps consistently below zero degrees F I wouldn't think that would be too much of an issue.

Evaporation could definitely happen if you plan to be gone for very long, but if most of the water is gone anyway from the trap, what would be left to freeze?  (And now that you pointed this out, if I ever have to use this method, I will definitely use a plunger to get most of the water out of my traps before adding alcohol!)

I don't know about septic tanks in other areas, but mine is large enough that a small amount of alcohol from the traps and toilets in my house shouldn't be a high enough concentration to hurt the organisms... and I'm thinking it would be way less toxic to them than anti-freeze.

But it will be interesting to see other, better ideas that this resourceful community can come up with!  

Fair enough. I wouldn't trust in in my winter temperatures, but elsewhere it may be worth considering. Perhaps we can convince somebody to do a controlled test.

I'm still cautious about dilution though. 80 proof vodka is 40% alcohol per volume, which of course means that it's already 60% water. Toilet traps would be the hardest when adding antifreeze (or perhaps the thirstiest, depending on your perspective).

Kirsty Pollock wrote: not sure what I should do  - RMH out of the question - this is Germany!!!

Why?

This Kachelofen looks very close to a RMH:



https://permies.com/t/205158/Rocket-Mass-Heater-Kachelofen