best backup heat source

We are building a new house on our property and I've been thinking about heat sources. Yes, we are incorporating passive solar into the design, but in our region we can go through long periods without sunshine during the winter months, and a backup heating system is necessary (and required for permitting and financing).

Right now we are in a small mobile home that uses a furnace and forced-air system. The furnace requires electricity to run the fan, but is fueled by propane (we don't have natural gas in our area).

My choice is basically between a propane-fueled system such as the one we have now, or an electric powered system. While we do occasionally lose power here due to storms and such, a backup generator will take care of that and its rarely out for long.

We will also have a wood-burning fireplace insert for backup. There is lots of wood on our 4 forested acres, but for most of the year you don't want a fire burning for hours - it may be cold in the morning but can warm up to toasty temps, so having a heat source you can turn on, heat up things quickly, and then shut down when needed is preferable.

Traditionally, electric heat has been expensive. Here we use hydroelectricity, so it's pretty clean energy, but $$. We are planning to put solar panels on the roof, but as I said the sun doesn't shine much in winter when we would need to power the heaters. But I'm thinking about this new battery that Tesla is releasing at the end of the month, and what that might mean for the cost of electricity in the near future.

When you combine steadily reduced costs for PV panels, and new battery technology, seems to me that electricity may end up being the cheaper option in the long run. Any thoughts?

The passive solar house that I grew up in pretty much heated itself except during the early spring rainy season. We used a wood stove as backup heating. A fire first thing in the morning was usually sufficient. The county busybodies required a grid-tied heating system, so we installed baseboard heaters, but never turned them on.

If the choice is between solar electric and propane for a backup heating source I'd choose propane. Heating with electricity takes a LOT of electricity. Compared to the demand, solar panels produce only a little electricity and batteries store only a little electricity. For a space heating application, all available electricity would be used up within a day or two of being produced, but since the demand comes at a time of year when solar energy is the scarcest, and because conversion efficiency of sunlight to electricity is only about 20%, it's not a good fit. A tank of propane will remain ready for use for months, years, or decades. Solar electric equipment to meet a space-heating need would be much more costly to install and maintain than propane heaters.

Joseph's system is good. Either electric baseboard or ventless propane, do the absolute minimum for permitting and then a simple woodstove for a little heat when needed in the dreary times. But definitely propane if you ever plan to actually use it.

Hi Mariah,

I've run into this scenario many times in my off-grid jobs. My go to is the Rinnai space heaters that you can often find online for around $800 shipped. They come with a through the wall flue and built-in thermostat, so install is quick and easy; just plug it in and run a copper tube in from the propane tank et voila, central heating. They are about the size of a large suitcase and go up against the wall on the floor of the room that they are heating.

All Blessings,
Bill

Thanks for all the advice, everyone.

Yesterday I interviewed a general contractor who is knowledgable about green building techniques. He says that with conventional stick frame construction, with its vapour barrier wrapping (sadly, after years of researching breathable options, we opted out due to budget limitations), one really needs to exchange the air, and the best way to do that in these parts is using a heat pump. That requires duct work, and when you already have that in place, a furnace makes the most sense as a backup. Most of the year we can rely on the heat pump alone for home heating, and no fuel is needed, so the furnace wouldn't need to be used much. As Joseph says, the propane will just sit there until it is needed, so could be a cheap option.

thoughts?

I would not want to go to the expense of installing duct work for a solution I didn't plan to use. Ducts are filthy, noisy, and expensive.

Our utility coop sells Convectair electric wall heaters. We love them. Dead silent operation, per room solution. Our worst power bill (all electric heat, water, cooking) for a -5 degree winter month was $100. That was before we got the wood stove. Propane is just ridiculously expensive here, electricity is relatively cheap.

I don't know anything about heat pumps, but I've never heard of them being used for ventilation. That seems like using a sledgehammer for hanging a picture, I'd check that out with some other expert before committing.

Heat pumps are very common here, as we have mild winters. They serve a dual purpose: they exchange the air and heat your home.

"When a heat pump is used for heating, it employs the same basic refrigeration-type cycle used by an air conditioner or a refrigerator, but in the opposite direction - releasing heat into the conditioned space rather than the surrounding environment. In this use, heat pumps generally draw heat from the cooler external air or from the ground. In heating mode, heat pumps are three to four times more efficient in their use of electric power than simple electrical resistance heaters."

If we don't use a heat pump, if we use baseboards or wall-mounted heaters, we still have the problem of air exchange. This is critical in a tightly sealed and insulated home. The only ductless exchange systems I know of are the mini-split electric systems, but they are for single "hard to heat" rooms, like sunrooms or attics, and not designed to heat an entire home. They are basically mini heat pumps that you fit to each room.

It's really hard to make these decisions without knowing how it will be to live in the house. I don't know how much the passive solar will work in winter when we don't get much sun, and I don't know how often we'll need to use the wood stove, or how well it will heat the home. I'm a "verbal processer", so talking this out with you people is very helpful for organizing my thoughts.

Perhaps you could use a "Heat Recovery Ventilator" for the air exchange, very low power demand, and do a minimal get-to-code heat system.

Here's a DIY version for $100 from Make magazine's site.

Hi Mariah,

My parents house in Saanich uses a heatpump/oil furnace combo, with a fairly modern/efficient woodstove retrofitted in the center of the lower floor. The heatpump was replaced a few years back, so while it isn't cutting edge it's not ancient.

They run the woodstove most days in the winter, and whenever it's coldish in the shoulder seasons, which generally prevents the heatpump or furnace from being needed at all until late at night after the fire is long dead. A longer burning woodstove in a better insulated house would do even better; their house was designed by an architect who must have thought this was California. TONS of glass, pointing every which way, in the middle of the woods; not a lot of solar heating going on.

I think this set of 3 works pretty well together for a poorly insulated hose, for people who don't want to be completely reliant on the woodstove for cold weather heat. It utilizes the big upside of a heatpump, which is that for the shoulder seasons when the temperature is right, you can get 2-3x the efficiency of a baseboard heater. The downside, aside from ducts, is that heatpumps lose efficiency at lower temperatures; once it gets cold enough that they don't work at all; 'cold enough' varies from model to model. When you most need heat, the heatpump is at its worst. In my opinion one should have a primary and backup source that actually work in cold weather... so that would mean 3 heat systems total. All of them will need to be maintained and eventually replaced.


Seems to me that a well insulated passive solar design shouldn't really need all that much supplementary heat in the shoulder seasons when a heatpump is at its best.

A woodstove/insert should be much more useful in a house designed around it, as you can extend the heating effect with thermal mass, and should require much less heat to begin with through better insulation. As Joeseph mentioned, a morning fire would likely by right for quite a few of the shoulder season days.

If your house is designed to work well with wood heat, an unducted auxiliary heat source placed by the woodstove/RMH should also work well. The one suggested by Bill sounds good to me, cheap and simple!


This just leaves ventilation to sort out. I'd try and solve this with an ERV/HRV with a minimum of ducting; I would be interested to hear why your contractor prefers a heatpump. The design of the house is rather relevant, though; how many rooms, how big, layout... I don't see how my parents place could be ventilated without the convoluted ductwork, but other floorplans would be much more workable for this.

Another thing that I like is standardized fuel sources for fuel dependent appliances; generator, heatsource, and cooking source. Propane vs diesel for this fuel would be a whole nother thread... but it is worth thinking about IMO.

Thank you for that link, Ann, it was a very good explanation of HRV systems, one of the best I've read so far. As seen in the article, however, there is duct work required, and adding a furnace makes sense given the duct work is already there.

Dillon, I really appreciate you sharing the experience of your parents' house. I, too, have parents in Saanich (Prospect Lake area) who use a heat pump. My Dad swears by it. They are shaded by trees as well. You've reminded me to pick their brains about the day to day use of their heat pump, wood stove, and backup system (in their case, an ancient but well maintained radiant water system: looks like baseboard heaters, but with water).

The floor plan of our home is already set. It's 2000 s.f., roughly 70 ft long and ranges from 25 to 40 ft wide. Oriented with long side to the south, and arranged with central living areas in the middle and bedrooms on either end. The hope is that when the sun isn't shining, a centrally located wood stove will heat the living areas during the day, when bedrooms are not being used. Honestly, I'd be happy to leave it at just that, but apparently we need a better "backup system" to make the bank happy (for "resale value", although I plan to die on this property!).

Thanks to the helpful discussion here, I'm leaning toward the furnace. It's likely we will barely use it, so maybe better to have a backup that is out of sight rather than electric heater units along walls, etc. If we had the time and money to do a cob or other such breathable home, it would be a different story. Maybe when we build our retirement cottage on the property and hand the big house over to the kids we can do that!

Hi Mariah,

My building scientist side has to ask; what kind of vapor barrier are you planning on using and on which side of the wall assembly will you install it?

Then I must ask; why? Do you really want to live in a sealed home with chemicals offgassing for the next 25 years?

You say that you can not afford breathing walls, but drywall is breathable and plaster can cost about the same as a high quality low voc paint finish. Then there is a hybrid finish that is somewhat breathable and actually faster and cheaper than latex that Ryan Chivers was telling me about, where you tape and mud, then paint with low voc primer and quartz sand and finish with a 1:1 mix of lime and marble, plastered on with a sponge float. This is a very DIY friendly approach.

Since this is something that I am extremely passionate about, I am willing to talk to your contractor for you if he has resistance due to lack of experience with these natural/hybrid systems.

All Blessings,
Bill

Hello Bill,

We have only just chosen our GC, who is knowledgeable about green building systems. We have not yet sat down to chat about the details on how to make this home as green as we can, while sticking within our tight budget. So he may come up with ideas I don't even know about yet, such as the hybrid system you mentioned (which I'm not familiar with).

In the meantime I have been intensively researching the topic of building green with stick-frame construction (ecohome.net is providing me with endless information!) and the message I am getting is to build it as airtight as possible, overinsulate (while reducing thermal bridges) along the lines of the PassivHaus system, and use an HRV system for fresh air exchange. If one choose the finishes carefully, low VOC paints, concrete floors, etc, there should not be chemicals off-gassing in the interior environment.

You asked about the vapour barrier: we live in a temperate climate where we don't need air conditioning systems in the summer. In winter, we have the unusual situation of being somewhat cold (temps may dip below freezing a handful of days but will stay close to zero most of the time) but very humid. In most cold climates, humidity readily moves from inside to outside the house in winter, along the gradient. Here, the gradient is much less steep and moisture can become trapped in the walls (which is why straw bale is largely frowned upon here, and must be used with a lot of caution). I don't know if this makes a difference with what I have learned thus far (without having had the chance to discuss this with our builders yet), which is that the vapour barrier should be on the warm side of the insulation.

As for what kind of vapour barrier, I am currently studying the topic. I've learned that there is a difference between an air barrier and a vapour barrier and I'm still trying to wrap my head around that. Again, I haven't discussed this with our builder yet, but ecohome.net offers some interesting options, such as putting the sheathing on the inside. http://www.ecohome.net/guide/interior-sheathing-air-vapour-barrier


I should also point out that my husband and I have zero DIY skills and not a lot of time to do labour on the house ourselves, which is why things like cob and natural plastering, plus the maintenance involved, are just not in the cards for us.

With that said, I would be pleased to hear any suggestions you might have. I am eager to learn!

Bill: here is an article on using paint as a vapour barrier...is this what you were talking about?

http://www.ecohome.net/guide/painting-vapour-barrier

Hello Mariah,

With that said, I would be pleased to hear any suggestions you might have. I am eager to learn!

I kind of "sat back" on your post to get a better feel for the direction your project was intended. I understand, as with many, the budget is tight. It would also seem that there is a reasonable interest in "natural building methods"...so that is a big plus also. Bill has already "hinted at" some of the exact same points I would have. I will try and go through and critique/respond to certain highlights. Hope they are of some use...

Heat pumps are very common here, as we have mild winters. They serve a dual purpose: they exchange the air and heat your home. ..."When a heat pump is used for heating, it employs the same basic refrigeration-type cycle used by an air conditioner or a refrigerator, but in the opposite direction - releasing heat into the conditioned space rather than the surrounding environment. In this use, heat pumps generally draw heat from the cooler external air or from the ground. In heating mode, heat pumps are three to four times more efficient in their use of electric power than simple electrical resistance heaters."

When I hear/read "heat pump" I basically take several steps back. This is more modern "technology" that functions as much on theory, "it should work" and "I think" concepts than actually functioning as intended. I always reading all the "positives" about it...and 99% of that comes from those that either directly or indirectly sell or benefit from it. The base element for me is this form of heat ultimately usually facilitates a "convection" system...which is the least desirable form of heating. It is also entirely to "technology laden" for me. It isn't a matter of when something will break, but when. Then there is the cost of these service issues. Some basic things to understand and know about "thermal regulation."

Thermal Regulation of both body, and architecture is done by:

Conduction
Convection
Radiation
Evaporation
Respiration

With a fan blowing (i.e. convection, evaporation) on us (a.k.a. Heat pumps) at 80 degrees will lead to hypothermia and death within 12 to 24 hours. Yet sitting on a 80 degree warm floor has a different effect entirely. Even with this physiological fact...80% of the HVAC contractors will still try to sell "forced air" cooling and heating systems with all its moving parts, ducts and related silliness...and not "radiation systems." Just one more bit of illogic and corruption within the building trades today...and what has become another illogical part of "building habits" vs. "good practices in architecture."

We have only just chosen our GC, who is knowledgeable about green building systems. We have not yet sat down to chat about the details on how to make this home as green as we can, while sticking within our tight budget. So he may come up with ideas I don't even know about yet, such as the hybrid system you mentioned (which I'm not familiar with).

This is a "toughy" without sounding too critical or harsh...but...being "knowledgeable about what is being called "green building systems,"....and...being a traditional-natural design builder TNDB and/or knowledgeable about permaculture principles as it applies to architecture is two very different things. BE CAREFUL in your selection of a GC and vet them well...

In the meantime I have been intensively researching the topic of building green with stick-frame construction (ecohome.net is providing me with endless information!) and the message I am getting is to build it as airtight as possible, over insulate (while reducing thermal bridges) along the lines of the PassivHaus system, and use an HRV system for fresh air exchange. If one choose the finishes carefully, low VOC paints, concrete floors, etc, there should not be chemicals off-gassing in the interior environment.

The above quote is exactly what you do get from most, "green building" sources today. We in the professional trades of TNDB tend to call this "green washing." Much (most??) of what is offered in today's "green movement" is nothing more than a "rebranding" of what contractors and their supporting industries have always done, or atleast have done since post WWII and the IR (Industrial Revolution.) Just going to the link you provided about,..."INTERIOR SHEATHING AS AN AIR AND VAPOUR BARRIER 3/4 inch OSB sheathing on the interior can be an excellent air barrier and a great vapour barrier as well"...and seeing the picture, while scaning what is written, I can state with some authority that very little there is either natural, sustainable and definitely not traditional. The first photo is...for all practical purposes...a conventional stick built structure. This is what I was speaking about when I mentioned "rebranding." This architecture...with its OSB, OPC foundation, monocultures wood studs and related "means, methods, and materials" are virtually unchanged in what 90% of the subdivisions have seen built in the last 40 years. This is neither "green" nor sustainable, has a huge carbon footprint, and definitely is not natural...

As for what kind of vapour barrier, I am currently studying the topic. I've learned that there is a difference between an air barrier and a vapour barrier and I'm still trying to wrap my head around that. Again, I haven't discussed this with our builder yet, but ecohome.net offers some interesting options, such as putting the sheathing on the inside. http://www.ecohome.net/guide/interior-sheathing-air-vapour-barrier

Modern vapor barriers are more "concept" and "it should work" than actual proven system of functionality and "good practice" in architecture. None have been around more than 60 years and most less than half that time. The entire concept of "air tight" architecture will take another 30 years before the lawsuits and realities of "building sickness" actually gets "driven home" with most consumers. It was the same with DDT, Chlordane, Lead Paint and Asbestos. Once a "building concept" become habitualized, it is virtually impossible to stop it, especially in today's "throw away consumer society" that is so jaded by the industrialized market advertizing. I would just offer these Permies.com conversations/post as food for thought...

Breathable Walls

"Build tight, ventilate right."

Raised Earth Foundations

Condensation, and other moisture related challenges in natural building...

As a short answer...vapor barriers and "air tight" architecture doesn't work...Like many things today, too many are "trying" to "make it work" and some may....for a short while. Nevertheless, it isn't a matter of if...but when...they will fail...

I should also point out that my husband and I have zero DIY skills and not a lot of time to do labour on the house ourselves, which is why things like cob and natural plastering, plus the maintenance involved, are just not in the cards for us.

I can understand and appreciate that, as those are the core of past clients. I do have to share though that I spend a huge amount of time "re-educating" consumers about traditional/natural building. These T/N systems are not less difficult to "maintain" than any modern system, and often much easier, depending on one's aesthetics. I do these posts as much for the OP as other readers, as I worry that too much "misinformation" get repeated about T/N regarding things like "being too expensive"..."can't be done"..."hard to maintain"..."can't find a contractor..."

It's really hard to make these decisions without knowing how it will be to live in the house. I don't know how much the passive solar will work in winter when we don't get much sun, and I don't know how often we'll need to use the wood stove, or how well it will heat the home. I'm a "verbal processor", so talking this out with you people is very helpful for organizing my thoughts.

I should be around a phone parts of next week. If you give me a time, I would be glad to speak with you on the phone...

Feel free, in the interim, to ask any specifics you wish to...we all love to help...

Regards,

j

Hi Jay. I really appreciate you taking the time to discuss all this. I'm always impressed with how generously people on this forum share their knowledge!

More about our project: our initial plan was to do a natural building method. We are lucky to live in a place where this is not an unknown concept. My community and surrounding area is home to several cob buildings and techniques such as straw bale and chip-slip and natural plastering are well known here. We interviewed many people who are professionals in that field. What we learned from all of them was that in our particular climate, where humidity does not always flow easily out of the walls during our warm and moist winters, these techniques are still considered "under development." Our friends have lived in a load-bearing cob house for 4 years now, so I have spoken personally with people living in and maintaining these homes. Cob is a poor insulator and plaster needs regular repairing of the cracks that form, straw bales get wet inside (some have tried to mitigate this by sandwiching the straw between thick cob walls), etc. Most people who have built natural homes here have put huge amounts of their own time and labour into the projects to make them affordable. That is not an option for us. So after 3 years of research, the overall impression we were left with is that it is still experimental here - enough that we are not willing to risk the biggest investment we will ever make - and simply too expensive for our budget and desired floor space (which I've pared down as far as I'm willing to go).

We also are borrowing money to build this house, so the bank has some say-so in what we build. It must carry a new home warranty, etc. so we are not able to go too far outside the box. With that said, the powers that be and our local credit union are more familiar with green building methods than perhaps most communities in Canada and US.

I've done a good deal of research to find the right builders, and as I said there are plenty of examples around here, and its not a big community, so all in all I feel good about who we will go with. The GC's partner is a certified building biologist, trained in Germany. We met with him a couple years ago back when we were trying to build natural. We have a guy putting my hand-drawn floor plan and sketches into a proper plan, which he will then give to the building biologist and we will be meeting to discuss all the details of what we can do to make this as "green" as possible - such an overused word, but my main focus is energy efficient, potential for off-grid (passive solar, active solar).

Now, on to your comments/questions. Heat pumps most definitely do work: my parents have had one for about 15 years and I have had detailed discussions with them about how well they work, effect on heating costs, etc. In fact I have spoken with many people who use them as they are very common here. I'm satisfied that they do what they claim to do and are particularly well suited for our climate. With that said, I am with you on the forced-air method - honestly, I really want to avoid it. But I don't know what the alternative should be. We probably can't afford in-floor radiant heating. My parents have a baseboard system that uses water instead of coils, which is circulated through the house through various baseboard units. Is this what you are referring to when you suggest using radiant heating?

Yes, the Ecohome site is based on the usual stick-frame construction. But I don't understand why you say that is necessarily unnatural and unsustainable. I live in an area that is rich in wood as a local resource - in fact we will be using some of our own lumber milled from trees felled on our property in the project.

Breathable walls: whenever I read about breathable walls they all seem to leave out my circumstance - a climate where the winters are relatively warm and very humid. A breathable wall only works if there is a humidity gradient. When you have a warm, humid interior of your house, and a slightly colder but still humid exterior, the moisture just doesn't move much. It can sit there in the walls, and that is why straw bale is considered a heavy risk here. I would like to hear about breathable walls in the context of an environment with warm, wet winters with high humidity.

I'm off to a Mother's Day brunch but when I get back I plan to read the discussions on the links you posted (thank you for that, btw!). In the meantime, if you could perhaps explain more what a breathable wall system could look like that ISN'T cob or straw, a description would be much appreciated. You mentioned drywalling, special taping and I'm curious what the rest of such a wall would look like.

I thank you again for putting the time into this discussion - I'm excited about discovering new solutions, perhaps I can have a greener home than I thought!

The first thing I thought of was radiant floor heating and I don't think it's very expensive actually. Especially in the long run with operating costs the ROI is very good. You may want to look into it a bit further. Have you looked at bullditsolar.com at all? Might get some ideas there and there's radiant floor heating info there.

I've been told around $15000 to $25000 installed. Doubtful it will make it in the budget, but I'm still holding it open as an option.

I think the best back up heat is a wood stove. I built and live in a Passive, super insulated house. We have 4 heat pumps to heat/cool the house along with the Heat recovery system to cycle the air in the house and exchange it with fresh air. When I built the house I couldnt afford cost of installing a passive house approved wood stove (becuase of the tightness it needs to have a direct cold air vent. This last winter was the first winter we lived in the house and I wish we would of had a wood stove. The house stayed warm but we spent more on power then I thought we were going to. (it was much less then the oil bill was at our old house but still) We are looking at installing a woodstove this summer/fall. The passive aspect of the house worked wonderfully even when it was below freezing if the sun was out we had to turn all the heaters off in the house, you would have to turn them back on by 4 for the evening. I would also suggest insulating the floors, by builder said we didnt have to worry about that but our basement is unheated and the 1st floor got very cold which made the 1st floor cold. I plan on blowing insulation into that floor this summer/fall as well. We have only lived in the house a year in june but we are happy with it minus the few things I have mentioned here.

Adam, thank you so much for sharing your experience with a passive, superinsulated home. This is what we are aiming for, and it's great to meet people who are already living the experience.

We will definitely be installing a wood stove, mostly because our property is heavily wooded and we have ready access to free firewood and kindling. We rarely ever need heat on at night, so it would serve as a good backup heating system during the day when it isn't sunny (which happens alot here in winter).

I'd also like to know more about your heat pumps. Since you have multiple ones, I'm going to guess they are "mini splits" and therefore ductless. How would you compare those to a central duct-system heat pump, are you happy with them?

I am now leaning toward a slab-on-grade rather than crawlspace foundation, encouraged by my builders, and so the floor will definitely be superinsulated. We are also thinking that with the savings on going slab rather than crawl, we may end up being able to work radiant heating into the budget. I'm a bit leery of it - seems like an expensive and complex system for something we may not have to use most of the year! The idea of having water pipes, even plastic ones, embedded in concrete where they are inaccessible makes me nervous.

So that's the dilemma - we just don't know how often we'll need to rely on backup heating, especially if we have a heat pump and a wood stove, and paying a lot for a system we may rarely use doesn't sound smart.

We run Mitsubishi split units, they are ductless, we have two downstairs, one in the upstairs hallway and one in the master (this one is the additional one). We normally only have to run one downstairs during the winter (we do keep them set at 63-65 degrees) They dont seem to shut themselves off so when the house gets comfy we shut them down. We also installed ceiling fans so it would help the air circulate better, that seemed to help with any cold spots. The Mitsubishi ones are the only ones designed for colder weather, they lose effecincy at about 10 degrees and they aren't tested below -13 degrees. Ours continues to work this winter but they did freeze up on us one time and while they were still "working" we needed a tech to come out to get them unfrozen. They should be covered and when we put a deck on the house with snow fence around them it should help with that issue. For back up heating we have electric heaters installed in the walls, this was done by the contractor due to the concern the split units wouldnt work during the extreme winter months. I don't consider them a true back up heat becuase they also rely on electricity (as everything in my house does). We did lose power during the thanksgiving storm and the house never got below 60 degrees for the 2 days we didnt have power. The biggest thing when you go to size your wood stove and heating systems is you need very small systems. the split units produce about 15,000 BTU's I have 4 so the most I need it 60,000 BTU's most woodstoves are designed to put out 150-200,000 BTU's which is why you need to look for ones designed for passive/super insulated homes. There is a company in canada that makes one which also has 150kg of thermal mass, this is the one I want to instal in my house. The other ones come from europe, any green building supply company should be able to locate the correct stove for your home. I think the home is what you make of it, my mother in law hates our home and says it is to cold, however when we visited everyone during the holidays we noticed most people keep there heat on 75-78 degrees where we leave ours on 65 at the most. Also the fresh air is constantly flowing into my house, for example if you are mowing your grass the house will smell like fresh grass. If you go super tight construction you need the air exchange system.

The biggest issue we had was finding a contractor that understood what we were trying to do, and even then his subs were completely shut down by any sort of alternatives we wanted in the home. The other issue will be getting financing, if you go that route. Banks will not appraise the home correctly to account for the additional money needed for the construction.

Hi Mariah,

1) to address your initial query, wood is the best backup heat source, but I would use a hydronic distribution system. Then you have the option of electrically heating the storage tank as well. I like Runtal radiators, not in-floor plastic pipes for this.

2) Hygrothermal performance of mass walls is poorly understood by nearly everyone, especially the green building folks. If interior and exterior RH are equal and you are heating the home, moisture will drive outward and if you are cooling the home, moisture will drive inwards. Latent heat in the water vapor will warm or cool the wall according to season. This is a large effect that should not be ignored.

I used to be a home performance contractor, BPI certified, Utah HomeStar and all that, but my blower door hardly gets used anymore, because that is not the way to create comfortable homes with low ecological impact. I rely now on breathing walls instead of contraptions that may or may not function when needed. I would suggest that you look back at Jay's comments and think about thermal and hygrothermal performance as well as air/sound quality and how the walls can be designed for a best of both worlds approach.

What initially got my attention was the utility bills of clients with new houses were so much higher than my 120 year old uninsulated 3 wythe adobe home with original single pane windows and lime plaster.

All Blessings,
Bill

Thanks for the detailed reply, Adam. I appreciate the info, esp the BTU stuff. really good, thank you.

Bill, I appreciate what you are saying, and if my circumstances were different we might pursue a breathable wall system/natural building. You and Jay are way ahead on the path compared to where I am right now. I'm just not there, not in terms of time, resources, etc. And this house needs to be built now.

With that said, our longer term plans are to hand this house over to the kids, whoever has a young family first I suppose, and we'll build a small retirement cottage elsewhere on the property. That is something we could think about doing as a natural build. We've also talked about doing some cob outbuildings on the property to get us more confident with the system and perhaps learn how to DIY some of it.

Hello Mariah,

Like so many "positives" about us as individuals, there too we often find our weaknesses. There was a simple question to this post:

"best backup heat source..."

To that I would say:

1. Wood heat in a radiant system like Masonry Heaters (RMS, etc) or a less efficient simple soapstone wood stove of some fashion...

2. Some form of hydronic radiant heat would be the second choice with the least amount of moving parts to the system. One that is easy to service or replace when the time "DOES" come with all thing technology based, such as Bill suggested...

I shared more only as an FYI, as the old adage goes about "leading a horse to water..." I may inevitably share too much information perhaps. Nevertheless, the path is now opened and thoughts exchanged so to the current responses, I must address certain points...

...initial plan was to do a natural building method...our particular climate, where humidity does not always flow easily out of the walls during our warm and moist winters, these techniques are still considered "under development."... Cob is a poor insulator and plaster needs regular repairing of the cracks that form, straw bales get wet inside ...So after 3 years of research, the overall impression we were left with is that it is still experimental here - enough that we are not willing to risk the biggest investment we will ever make - and simply too expensive for our budget and desired floor space (which I've pared down as far as I'm willing to go).

I will try to only address the high points once more for clarity of all that reads Permies.com.

Natural building is not "under development," not by any means or good understanding, and why I address it as traditional/natural (t/n) methods. Now there are many (too many) trying to "reinvent methods," reinterpret methods, and perform this work with only half the information they should actually have about t/n methods. This is a reflection of poor understanding and facilitation of "good practice," not a matter of something being "under development." I can respect 3 years of research and appreciate DIYers, clients, and consumers that do such due dillagence, and further understand the overwhelming amount of information there is. However, "3 years" of research is not the same a s 35 years of it and doing the work...So with that, I spend the time here to give the most complete package of information I am able for public consumption. If it is consumed (and used)...that is grand...if not, so be it...

We also are borrowing money to build this house, so the bank has some say-so in what we build. It must carry a new home warranty, etc. so we are not able to go too far outside the box.

Virtually every method I promote within the t/n arena is more than accepted by lending institution...especially today because of the "green movement." It is a matter of "clout" and proper semantics as a professional builder to frame a "design" for the lending institution to understand in the...proper context. If a less experience design/builder or client is not equipped to use the proper terminology when requesting fiscal support of a project...it is the lack of being able to "reframe" and "rephrase" the methods properly that becomes the issue...NOT the means, methods and materials themselves... When someone speaks of these as "new age"-"mud building"-"hay and grass walls" or related misnomers (which I have seen done too often) then this design/builder who must step up and address this lack of understanding and proper nomenclature.

SB (straw bale), mass wall earth architecture and other mass wall systems (e.g. log, stone, brick, eb, fossorials, etc), natural cellulose and/or high loft matrix (sawdust, wool, mineral wool, light straw clay, perlite, pumice, expanded clay, hemp, etc, etc) have all been around for hundreds and in most cases thousands of years...There is nothing "new age," revolutionary or "under development" about them or the...proper terminology...that should be employed when an erudite conversation or documentation is to be facilitated.

I've done a good deal of research to find the right builders, and as I said there are plenty of examples around here, and its not a big community, so all in all I feel good about who we will go with....

If the selected GC has been doing this work for over 30 years (or more) in multiple mediums or the knowledge there of...from timber framing to fossorial forms of architecture, etc, then the selected firm is in good order. If that level of understanding and/or chronological CV is not present, then I would challenge if the experience base is actually there to address all the information thus discussed in this post. I mean not to sound harsh, yet I meet many that have very open views of t/n and are learning fast how to really make these systems work, while others are more interest in what "they know" and spend more energy facilitating "what they understand and can do," while often undermining client desires and project goals, as well as, perhaps more applicable means, methods and materials for a location's optimum design parameters to only fit what they "the contractor" thinks is profitable or easier for them to do.

A good GC will make a project's parameters work, unless they are actually fiscally or physically unachievable...Most t/n method parameters are, or can be, cost and time effective in most cases. It is the lack of a thorough understanding of these t/n systems or of applying them applicably for a given biome by a client or contractor that becomes the issue...

Heat pumps most definitely do work...We probably can't afford in-floor radiant heating. My parents have a baseboard system that uses water instead of coils, which is circulated through the house through various baseboard units. Is this what you are referring to when you suggest using radiant heating?

I don't believe I said the HP don't work, but tried addressed there expense compared to other systems, there "overburden" on "moving parts" and technology (they cease to work without power) and the fact that "most" of them are sold under the premise that attaching them to "duct work" is best practice...which it is not. Force air heating and cooling is the least efficient and healthy systems there are. That is not subjective information. Now if a HP is found, for whatever reason to actually be the least expensive "backup" heat source, I do strongly recommend it being attached to a "radiant heat system" of some form.

Baseboard systems all use water accept for very few that may use antifreeze or oil. There are no "coils" per se, yet rather a radiant finned tube, radiant pipe labyrinth, cast steel or masonry manifold or related structure to distribute heat within a mass..

I don't, and never have place "radiant tubing" in concrete as I don't typically spec' OPC in projects. I have worked with "in mass" (be it the wall or floor) radiant systems for over 30 years, and with one of the founding (holds many patients) and pioneering developer's (Robert Starr) of the current understanding in hydronic radiant systems. Radiantec systems are more than competitive with most HP and "mainstream" boilers and forced air (duct based) systems. So when I read someone state that these systems are "more expensive" I gather that all the information has not be found.

Yes, the Ecohome site is based on the usual stick-frame construction. But I don't understand why you say that is necessarily unnatural and unsustainable. I live in an area that is rich in wood as a local resource - in fact we will be using some of our own lumber milled from trees felled on our property in the project.

It isn't natural nor sustainable because of the way these forest are managed, the way the wood is harvested and processed and the way "most" contracts utilize these resources. OSB is not a "sustainable" system in most of the current permutations, though some made of bamboo, and agriculture byproduct are "trying"...yet still outside the envelope of more t/n modalites...

Just because someone lives in an area that has a "rich" wood resource, does not mean that is the wood going into local architecture. Actually that is seldom the case as most current GC (green or otherwise) use industrialized wood products, and don't own their own sawmills or work with other builders that do...Which I (and those like me) do and have for most of our careers. This is another criteria for what I would call a "real" t/n builder, and if vetting is to be done, then this is one of the criteria to be met. If this project is going to employ some of the properties "wood product resource" then I suggest it use only locally grown, harvested and processed wood as the only source or 90% there of. Another big plus if a GC can facilitate this...

Breathable walls: whenever I read about breathable walls they all seem to leave out my circumstance - a climate where the winters are relatively warm and very humid. A breathable wall only works if there is a humidity gradient.

I am sorry, yet this sounds more like a subjective "interpretation" or "repeated misinformation" than the actual characteristics of these systems. I must suggest that it is the "means and method" not the material matrix that is the issue. Breathable walls can work in any biome of the planet...and have for thousands of years...IF...facilitated by a knowledgeable and experienced builder...

Bousillage architecture (which I am helping a young DIYer with currently) has been around in the Gulf states, West Indies, and Central America for over 500 years...It doesn't get more "humid with wet winters" than that...This is but one of many methods germane to your location among others such as mass wood wall techniques, and related modalities. I can think of at least several... "mostly"... t/n and/or breathable building methods that could be designed (cost effectively and supported by banking institutions) for your region all under $350/ft2 "turnkey" perhaps even less, depending on size and design elements of the project.

...if my circumstances were different we might pursue a breathable wall system/natural building...I'm just not there, not in terms of time, resources, etc. And this house needs to be built now.

I can more than accept when somebody states, "no I don't want to do that" or "I don't understand," when selecting a building systems. That is their prerogative, yet I can not let the language pass that it is because these systems, take more "time," or "resources" or are not "cost effective." That is simply not the case...they are actually faster to build in most cases as the wall diaphragms do not have the added burden of OSB, house wraps, plastic paints, OPC stuccos, and other cladding systems of modernity to contend with. Timber frames for the average house are cut in less than three months, and raised/installed in less than a week (most in one day for average homes) and the cladding with thermal envelope only takes another month at best, then the fenestration, hvac, and related mechanicals are dealt with as usual for the most part.

If dealing or considering strictly a heave earth based mass wall or fossorial system, these can be more expensive in some cases and a bit slower to build...

With that said, our longer term plans are to hand this house over to the kids, whoever has a young family first I suppose, and we'll build a small retirement cottage elsewhere on the property. That is something we could think about doing as a natural build.

I wish you all the luck with whatever system you finally select, however I must stress to others reading this, it is a "choice based decision," not a "can't have it natural" factor...as that is not fair to others in your area that may be considering these t/n methods...

Respectfully and with good wishes to your final successes in building...

j

Hello Jay, and thanks for your reply. When I wrote my last reply to you, I had not read through the links you gave me to the other discussion threads. Having done that, I now have a context in which to place what you are saying and what perspective you are coming from. I'm pretty blown away by your background!

I want to start out by saying that I am convinced you probably know far more about this than anyone I've spoken to. I would not disagree with much of what you have said here, and I certainly don't consider myself knowledgeable enough to suggest anything otherwise. I'm glad that you posted what you did, as I too think it's always good to consider other readers who may have questions of their own. So thank you. Thank you for sharing your time and wisdom with me and the others who are reading.

I can't emphasize enough that I really hear where you are coming from, and in a perfect world I would fly around the world getting myself convinced of everything you say, then fly you up here and have you build a beautiful natural home for us. But I can't, and there is nobody around here telling me that I can have a natural-built home within my budget (and size requirements). In the end, I am limited to the resources (in terms of knowledge, expertise, skills) that are available to me and I don't have time to acquire all that myself. The doubts I raised in regard to climate, etc may in fact be false concerns, but if the only people I can find here to build that way are saying this, I'm kind of stuck, whether it is true or not. Can't put faith in someone who has doubts themselves, kwim?

And that takes me to the heart of this discussion: I agree with you that my choice not to "build natural" is not because it can't work, and I am even willing to believe that the limitations of our climate are not an obstacle. The reason I have chosen, yes chosen you are correct, to go "conventional green building" is because I lack the resources to pull off what you call t/n building given the boundaries I have set for the project (eg. cost, size) and the local expertise available to me. At this point, I remain pretty uncomfortable with the idea of going "natural build", whereas I feel very comfortable with conventional green building, and perhaps that is reason enough to proceed as planned.

My evidence in talking with those who have built natural homes (cob, etc) here is that it is very expensive if you have to hire the labour to do it because cobbing, mixing clay-slip or chip-slip, and natural plastering is labour intensive. You may say it should not be expensive, but if I can't find someone here to say "yes you can do this, and within your budget" then I'm stuck. However, I'm not sure if you and I agree on what is a reasonable price. In regard to "Bousillage architecture" you wrote: "all under $350/ft2 perhaps even less depending on size and design". That is crazy expensive for here. Conventional building is around $140-150 s.f. and for natural homes I was quoted between $250-300/sf which we thought was an insane amount of money.

Now, on to questions: you mentioned "natural cellulose and/or high loft matrix (sawdust, wool, mineral wool, light straw clay, perlite, pumice, expanded clay, hemp, etc, etc)" - are these infill materials? I've seen a variety of natural infill materials, typically with timber-frame skeleton, though I can't see why stick-frame would not work too (timber framing here is for luxury homes and the contractors who do it charge $$$). Assume a stick-frame exterior wall with some kind of natural infill such as mineral wool or packed cellulose, etc...what would that look like if there is no air or vapour barrier? What cladding on the outside? What is on the inside (you mentioned gypsum and taping, I think? or perhaps that was Bill)? Or perhaps there is just no way to tie in what you are saying with a what we are planning?

As for heating, yes I want to avoid ducts, I really do. I wish that didn't leave me with plastic boxes attached to my baseboards or walls. The question is what do I need? No point spending $$$ on a system that we end up not using much because passive solar and wood stove do most of the work. OTOH, who wants to risk living in a cold house or relying on expensive methods to provide backup? I've heard tell that with sufficient insulation below a slab-on-grade concrete floor there is no need for radiant as the concrete will remain more or less at room temp. But I suppose you would not be happy with slab-on-grade or concrete, lol, so perhaps I'm asking the wrong person (I say that with a big smile and much respect!).

I would love to hear more from you about radiant heating. You say you don't do radiant in-floor heating in "OPC", were you referring to portland cement floors? So you put them in natural earthen floors, then? What about putting it in wall systems? We have talked about doing a wee bit of cob or clay-slip on a few interior walls to soak up the sun if we don't have a concrete floor (I'm much more partial to laminate hardwood flooring, which I'm sure makes you shudder, lol, but hey I like the look!), so perhaps we could run radiant heating tubes through there. I just don't know of anyone who has done that and why you would do that instead of in the floor.

I looked at the Radiantec website and the prices are certainly lower than what I have been led to believe, although they are a US company and we Canadians often have sticker-envy when we see what things cost us up here. Will have to look into this more. I'm supposed to meet with one of the guys this week to take a closer look at cost of radiant in floor heating.

Finally, you wrote:

"I wish you all the luck with whatever system you finally select, however I must stress to others reading this, it is a "choice based decision," not a "can't have it natural" factor...as that is not fair to others in your area that may be considering these t/n methods..."

I agree, and thank you!

Hi Mariah,

I sent you a "purple mooseage" (pm) here at Permies.com and will state publicly that I am at your service should you need further assistance...

...there is nobody around here telling me that I can have a natural-built home within my budget (and size requirements).

This...exact...project budget, nor the...exact...square footage and footprint design of the project you are trying to achieve has not been shared yet. I know folks all around the country (and world) that may be able to give you an alternative. I have also helped folks either locate new contractors to fill there wishes for a build and/or "re-educated" open channel current contractors in how to facilitate a natural build. There is no reason to give up as of yet, to just resigning yourself to what is offered in your area. One of the leading schools of timber framing ( Island School of Building Arts ) for example is in your region and produces many great framers the founder (James Mitchell) is a wonderful college and founding member of the craft in North America.

I lack the resources to pull off what you call t/n building given the boundaries I have set for the project (eg. cost, size) and the local expertise available to me.

Unless you have "broken ground" and poured the first load of concrete, there is nothing to lose in making a bit more effort in getting what your really want. Like I tell many students and/or clients..."let those of us that actually do the work tell you if it can be done for the time and amount you have..." I am not sure that all hope is lost yet, as you haven't actually shared much about the size or budget of the project with the members here. Many I know are just reading along, and if asked specific questions about size and budget, many here at Permies.com besides me can give good guidance there if it is actually wanted...

Perhaps a "mass wall" is not in your budget, yet that is not your only recourse. There are many "hybrid" and other "t/n" construction modalities that may very well be within your budget and time constraints. A simple timber frame with wall truss thermal diaphragm insulated with mineral wool batt and board then a cold roof/rain screen wall system is very viable for banks, super easy to build, breathable and also has great resale value because of the super insulation and the aesthetics of a timber frame superstructure. So again, if this sounds closer to your original goal sets and/or dreams, please give me more details of your project and I can crunch some quick numbers for you as $150 to $180/ft2 is achievable in many regions. Often it is the GC that doesn't want to take less or risk spending more time perhaps learning something they didn't know...rather than it not being achievable. I often will 'take less in profit" to give a "good product" over the alternative of unsustainable materials and environmental impact they cause...Actually the national average for architecture is $80 to $120/ft2, so yes what I gave is well outside that realm of pricing, but that is the average for most "high end" t/m builds...That isn't what we may be discussion here...I just don't know as I don't have all the facts...

Now, on to questions: you mentioned "natural cellulose and/or high loft matrix (sawdust, wool, mineral wool, light straw clay, perlite, pumice, expanded clay, hemp, etc, etc)" - are these infill materials?

Yes they are, or better yet..."fill in methods" as they have no mass. My gut (and probably your bank) is telling me that a mineral wool thermal layer will serve you the best for the budget and time constraints, perhaps with a "mass wall" designed for a later date within the structure that you can do yourself as time allows. I am not feeling that you are getting the "design services" for this project that is deserved.

I've seen a variety of natural infill materials, typically with timber-frame skeleton, though I can't see why stick-frame would not work too (timber framing here is for luxury homes and the contractors who do it charge $$$).

That is greed and it is simply wrong...Timber frames do not have to be anymore expensive than most conventional average "box store" frames. We average a price of $30 to $40/ft2 for our timber frames and I know of and have done them for as little as $20 depending on location, client and circumstances. Your circumstances sounds like it would would more than fit that criteria...so for your sake and those others reading this...TIMBER FRAMES ARE NOT A LUXURY, AND THE WAY WE HAVE BEEN BUILDING WOOD STRUCTURES FOR THE LAST 5000 YEARS....!!...DON'T LET SOME GC's GREED AND IGNORANCE SUGGEST OTHERWISE!

Assume a stick-frame exterior wall with some kind of natural infill such as mineral wool or packed cellulose, etc...what would that look like if there is no air or vapour barrier? What cladding on the outside? What is on the inside (you mentioned gypsum and taping, I think? or perhaps that was Bill)? Or perhaps there is just no way to tie in what you are saying with a what we are planning?

For what we call a "down and dirty" t/n build...it is:

A simple timber frame desing usually in the Asian motiff (a.k.a. Japanese/Korean style)

Wall truss thermal framing 600 mm on center and a minimum of 300mm in width thereby facilitating faster electrical, hvac, and related mechanical instalation, plus nice "window seats" and deep wall embrasure style fenestration embellishments.

Mineral wool batt and board insulation.

Cold roof and rain screen cladding system of simple wood board (I won't build a structure that does not have a cold roof and rain screen system that is not a "mass wall" design and even some of them have this this design element for better venting especially in the roof.)

I would finish the inside in boar panel as well and for color I would mix (or have mixed) my own traditional oils and/or mild paints.

Foundation would be stone or brick unless too much a hurdle for the lending institution and local inspectors (sometimes this is...often is not) so a OPC steam wall or plinth system is tolerated, (geopolymers are taking off all over the country and can be found now in many locations...yours may have one now??) and then either a traditional "doma" entrance and egawa (small porch) all around the structure plinth foundation with insulated wood floor.

Metal standing seam roof or wood shake.

That is the basic package and often within your suggested price range...I would have to crunch local numbers to tell you details...

As for heating, yes I want to avoid ducts, I really do.

Then do it! Wood is wonderful but does require to "manage" wood like moving and splitting it. Around here we call it the "poor man's" daily work out and is a lot cheaper than a local "gym membership."

Get yourself into the structure with wood heat, then ascertain "empirically" what other additional systems will serve you best. Radiant heat can be added very easily later on if the building is designed by a competent designer in these t/n modalities....All systems should be "modular" in design anyway to facilitate future augmentation, repair and/or additions to the structure...

I am not opposed (I don't like OPC and what it does to the planet) slabs, if they are the only "good alternative" for a tight budgeted project and when geopolymers/limecretes become more common, as they will!, then these slabs may well become best practice for certain designs...Often they are not as inexpensive as many suggest. A raise earth foundation of tectonically stabilized gravel, geo cloth, and stone plinths with packed clay earth and raised wood "floating floors" in the 청마루 (Korean Cheongmaru) style are in the same price range...These to postings have photos of similar work and items worth reading for your future goals in building...

restored japanese hand tools

Limecrete flooring - what is needed underneath?

I would love to hear more from you about radiant heating. You say you don't do radiant in-floor heating in "OPC", were you referring to portland cement floors?

Yes, portland cement (OPC=ordinary portland cement and is the standard for acronym for meaning such) is something I try desperately to avoid and usually can...I also would never barrier a hydronic tube in the stuff unless the opc floor system is a modular tile than can be removed for servicing. An opc stem wall and wood floors or perhaps a local slab stone bedded in sand could be made cost effective for the "first floor" area or a section of it. This could be one of the "back up" heat zones.

So you put them in natural earthen floors, then?

Could do that, but again, I don't like putting anything...anywhere...that it can't be easily gotten to for servicing when (not if) it is needed...This practice is good for the trades and contractors as they get to "tear stuff out" and charge for it. Modulating and good design should be the law of building...it isn't! Remember...building codes are "minimums" not best practice...

What about putting it in wall systems?

Yep...you can do that too! Take a wall truss system create a "wainscot" modular framing for the lower wall sections, cald this in slate, homemade clay or glass tile (I have seen kilned green Heineken beer bottles made into large glass tiles for just this effect) or related heavy mass material and run your hydronic tubing behind it...

We have talked about doing a wee bit of cob or clay-slip on a few interior walls to soak up the sun if we don't have a concrete floor (I'm much more partial to laminate hardwood flooring, which I'm sure makes you shudder, lol, but hey I like the look!), so perhaps we could run radiant heating tubes through there. I just don't know of anyone who has done that and why you would do that instead of in the floor.

Who ever finally becomes your design facilitator for this build should be offering these natural to you as the make this project come together...that is the sign of an experienced professional. I can't see this build not having many "when the time comes" elements designed, but not built yet, should be part of the CAD model offed for the projects final consideration. These elements may not be achievable at this time but the absolutely should be planned and designed for. I am only against "LHF" materials if they are full of all the nasty stuff that most manufactures put into them...which is not healthy for you to live around any way. Wood floors are great, and I lay "green floors" (meaning fresh off the mill in this case as well as environmentally sustainable) all the time.

I looked at the Radiantec website and the prices are certainly lower than what I have been led to believe, although they are a US company and we Canadians often have sticker-envy when we see what things cost us up here. Will have to look into this more. I'm supposed to meet with one of the guys this week to take a closer look at cost of radiant in floor heating.

Good, don't feel shy about call them. They are great folks and will serve you GC well by talking them through any design.

Let me know if I can help further and do start another post about this project as it progresses with photos and any other things you learn along the way...

Regards,

j

Jay, thank you so much for your post here. I will PM you with project details at a later date. For now, I'm rather excited about the info you have given on wall truss systems, cold roofs, etc. (most of which I've had to Google just to know what you are talking about, lol). So two things I want to say:

1) What I'm telling you about my understanding of what options are available to me and costs are based pretty much entirely on my own research, chatting with people, but I have not yet had a chance to talk seriously about my project in detail with the GC and his building biologist partner. I'm realizing that perhaps I limited myself before I even got started. It could be that he ends up telling me about stuff you have mentioned here, so I don't want to write him off just yet, ha ha. What you have written here gives me hope that there ARE options that I don't know about and perhaps these guys will know something about it. Thank you for that!

2) I'm really pleased to hear that about these non-mass-wall systems you've described and I've got lots of questions. So...I'm going to start a new thread here for passive solar and hybrid t/n modalities as I think we've ventured far enough away from my OP. I have to go get my son off to his swimming but will post later today....stay tuned!

Hi Mariah,

Any good facilitator of architecture...like the ones I hope you are about to speak with...should be excellent "kit flyers," metaphorically speaking...

My job (and theirs) is to allow the clients dreams to fly as high as possible...we then negotiate the wind, amount of string available, and other conditions of the the day while we fly the kit that is your building project...

I look forward to more detail and your success in getting what you want in a new home...dream your dreams...please!!

Regards,

j