What is the Ideal storage method in new construction?

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Tom's well-taken points raise another issue.

Regarding the cost of expansion tanks for pressurized storage-- the Europeans apparently often use a "semi-open" system where the expansion tank is located relatively high in the building, above any of the served loads, and that expansion tank has a small opening at the top. The weight of the water from there down to the boiler at the lowest part of the system supplies a certain amount of pressure. Since the elevated expansion tank can be a relatively ordinary vessel (no need to contain actual pressure there, or have bladder, air, etc.) it can be fairly low-tech and inexpensive (compared to what we normally think of as "expansion tanks."

So, if building a building with an intent to run pressurized storage (if that is what one chose to do), perhaps try to build in (space-wise and structurally) a place for such an elevated expansion tank.
 
We are in danger of getting the which is greener, Prius vs Hummer type debate.

In Colorado with that load I could source it from mainly from solar, so I probably would not look any further. 100 sqft with storage, not sure quite how much, would take of most of the load.

I think it would be a hard sell except for most non committed wood burning types, and there is so much more low hanging fruit.

With regards to the semi open system, I know that is the norm for most residential houses, or certainly has been, I am a bit out of date. There are some issues, nothing is ever perfect, from dead birds in the tank to the need to make up evaporation loss and the consequent gunk that can come into the system, especially in hard water areas.
 
Floydian said:
I have been going round and round on this subject for the last year or so. Currently in the design phase of a house for my folks and obviously the heating system controls a lot of design aspects.

Construction will be 2x6 with sprayed in cellulose in voids. Then 2-3 inches of recycled 4x8 Poly Iso (sealing all gaps, cracks) then 1x strapping (vertical) 2ft o.c. then lap siding. Similar detail on vaulted ceilings and close attention to foundation insulating and this should be a house in the 10 to 12 btu/sq ft at design(0 deg F for us). R-3 Windows really stand out now in the heat loss calc but it gets hard to justify jumping up to triple panes when it means lots more money to burn a tiny bit less wood a year.

Solar thermal heating is the ultimate but when you start crunching the numbers(btus and $$$)it can get out of hand real quick.

Wood is the fuel source for us as we live on 72 acres of mostly wooded land and have always heated with wood. Now, to do it with maximum efficiency, comfort and convenience.

Masonry heaters are very appealing in a lot of ways. No power needed, High aesthetic value, efficient, comfy radiant heat, convenience of one or maybe two fires a day. From discussions with a couple of friends with MH they get a bit harder to control in the shoulder season as you are building fires based on conditions that are 12 to 24 hours away. This makes overshooting or undershooting a reality at times. Still they like the MH a lot but might do things different if starting over. Also parts of the houses that just don't get as much heat as they want and these are open house layouts.

Masonry boilers were discussed earlier. Check this out if you haven't seen it, its pretty cool:

http://heatkit.com/html/lopezs.htm

Of course now your adding electrical requirements and negating one of the big advantages of the masonry heater. But now you can get more heat to the extremities of the house(Bathrooms!).

IMO the gassifyer+storage+low temp emitters comes out ahead in the end for efficiency, comfort and convenience. Like a masonry heater it is a high mass heating system but one where you can put the heat where you want it, when you want it. Plus DHW year round.

Man, I can't wait to get my Varmebaronen and storage set up. Probably about the spring time :)

Noah


Just wanted to make a comment on your insulation. Although the manufacturers of polyiso suggest using it as sheathing I feel that if it has the foil surface it becomes a vapor barrier. Applying it to the outside of your insulated wall could cause it to trap water in your insulated stud bays. The instructions for installation call for a metal strip to be applied along the edge for air flow which I think defeats some of its insulating value.

Over the years, I have used it on several projects but I applied it to the interior of the studs and applied the wallboard over it which was a pain in the you know what but along with insulating, it provided me with a vapor barrier and it isolated the sheetrock from the studs allowing the sheetrock to contribute to the thermal mass even on the outside walls.
 
This could become a very very long thread.
I like the Lopez masonry boiler.
If you read some of the description, they talk about it overheating the space it is in.
Something like this really screams for either very good insulation (like a Seton, etc.) or installation
in a space that needs a lot of space heat that would come off the shell like a masonry stove.

Regardless, it is for a high heat load space as constructed on the website.

On insulated sheathing: In our climate, here in Maine, the guideline is that if it is over R-10, the wall cavity will be
above the dewpoint and condensation is not a problem. More is better.

If one has the luxury of building a new home or completely renovating an old one, insulate the hell out of it.
www.building science.com is a great resource for concerns about how to avoid expensive mistakes.

If a building is superinsulated, all other heating choices become a lot less expensive.

You only buy insulation once.
 
well this thread has really thrown me for a loop, but as this is my first post on here i'll start by saying hello. i live in central NH and am planning on building a new house(probably around 1800 sf ranch) either this summer or the next on an 8 acre lot i just purchased. ive been reading on here for a few weeks now as i am pretty sure i want to install a wood boiler in the new house. but then i stumbled across this thread and some people are saying that in a new construction with good insulation a boiler might not be the way to go. some are suggesting a masonry heater(which i had never heard of until today) and i think someone else said a plain old wood stove would be plenty to heat a new house. as i said i dont really know much about a masonry heater but it seems to me that it would have some trouble evenly heating the entire house, especially if you dont necessarily want all your bedroom and bathroom doors open 24/7. i appreciate the fact that it requires no electricity to operate, thats a great feature, but not at the sacrifice of comfortably heating the ENTIRE living space. and what is the price of having something like that installed? i checked out the link with the masonry boiler, pretty cool idea, but is it a realistic option to heat my house? and how hard would it be to find someone that could install something like that? someone also said that a wood boiler is good for a house designed around fossil fuel but if you are building new you may want to look at going other directions, but arent i going to want some kind of backup system anyways like an oil burner incase i want to take a vaca in the winter or get injured and cant do the wood thing for a while? i feel more confused now than i was before i came here lol please straighten me out!
 
WEDONTNEEDNOOILLETTHEMOTHERBURN said:
well this thread has really thrown me for a loop, but as this is my first post on here i'll start by saying hello. i live in central NH and am planning on building a new house(probably around 1800 sf ranch) either this summer or the next on an 8 acre lot i just purchased. ive been reading on here for a few weeks now as i am pretty sure i want to install a wood boiler in the new house. but then i stumbled across this thread and some people are saying that in a new construction with good insulation a boiler might not be the way to go. some are suggesting a masonry heater(which i had never heard of until today) and i think someone else said a plain old wood stove would be plenty to heat a new house. as i said i dont really know much about a masonry heater but it seems to me that it would have some trouble evenly heating the entire house, especially if you dont necessarily want all your bedroom and bathroom doors open 24/7. i appreciate the fact that it requires no electricity to operate, thats a great feature, but not at the sacrifice of comfortably heating the ENTIRE living space. and what is the price of having something like that installed? i checked out the link with the masonry boiler, pretty cool idea, but is it a realistic option to heat my house? and how hard would it be to find someone that could install something like that? someone also said that a wood boiler is good for a house designed around fossil fuel but if you are building new you may want to look at going other directions, but arent i going to want some kind of backup system anyways like an oil burner incase i want to take a vaca in the winter or get injured and cant do the wood thing for a while? i feel more confused now than i was before i came here lol please straighten me out!

If I was building new and had access to natural gas I would super insulate, then put in radiant floor and a condensing boiler and forget about the wood. the $8,000 or so you save will buy a lot of gas. Just my 2cents.
 
Heat distribution

Insulated houses need mechanical ventilation, pull out the stale heated air and pre heat the incoming cold air via a heat exchanger.

Back up heat supply

Whilst you are not there the main requirement is to stop the building freezing. It will be -27F where I am tonight and I know people who have houses that will not freeze at these temperatures. Might be an extreme but if you can capture heat by design and stop it getting out then you are good to go.

Not everybody wants to go to these extremes so a small back up electricity/gas system would be the way to go, just in case.

There is a point of diminishing returns, which varies by individual circumstances. And individual location.

I like the idea that the house design basically takes care of itself and which I can top up if I want to be really warm.
 
Back to original question. I would design one wall with 4 propane tanks on end on the outside wall. Highly insulated with access from the outside in case you need to work on them. 5ftx15ft is the footprint and could blend in with the outline well. Install a drain in case you need to drain. I would then build a small building a short distance away for the boiler as I like the boiler away from the house but it could be put in the house if you want. Depending on location solar could be installed on the tank wall to supplement.
leaddog
 
Jags said:
Como said:
A new properly designed and built house of 2,000 sq ft would have a heat loss of less than 20,000 btu hr max.

Really?? I am not up to snuff on the new code and requirements, etc. Do you have any "favorite" place to sniff around at these designs? This is more on a personal level than with my friends question.

Heck - I think my bedroom requires 20,000 btu an hour. :lol:

Read Joe Lstibureks book about construction for cold weather climates. It's full of good ideas and proven methods that can easily get you down to 10 btu's / sq ft. If you are building a new home his book is the best investment you could possibly make. It should be mandatory reading for every builder in the Northern half of the US. Unfortunately most that I have shown the book to dismiss it offhand as a bunch of garbage. I don't like those people. They do a great disservice to their customers by using antiquated methods and materials.
Bear in mind that when you design for that level of structural integrity, mechanical ventilation and heat recovery are just about mandatory.

http://en.wikipedia.org/wiki/Joseph_Lstiburek

http://www.amazon.com/Builders-Guide-Climates-Joseph-Lstiburek/dp/B000OSLFWK
 
Couldn't agree more. His books & articles are all well worth the read.

The man definetely has his brain in the right groove...too bad so few North Americans realize the value of what he teaches & preaches. Others (western europeans) for example, take his teachings learn them, reproduce them, fine tune them & then resell them to us in the form of products & technologies. If we ever intend to get out or back in front we have got to start learning to listen to those in our own continent who are ahead of the curve instead of sending them abroad.

There I go again....asking us to think & learn....time for me to go find a brick wall....I feel a headache coming on. ;-) Time to go flatten my forehead again!!!! :shut:
 
On a more seroius note Jags. We are achieving a 10 btu/sq/ft on a regular basis here in the net zero homes constructed in the area. The newest generation of net zero homes has a goal of 5 btu/sq/ft. These are incorporating some newer tech such as grey water heat recovery. System uses a tank to hold grey water which is attached to a HX (filtered of course). Home heat calls look for heat at this HX first so as much heat as possible (without stopping the plumbing) is recovered. Even if all your friend can achieve is 10 btu/sq/ft in his new home. Well he may find that he needs far less storage than he first thought. Something the size of a bathtub may just do the trick. He wont need to replace the btu's he doesnt waste.
 
nofossil said:
My goal would be to have all of them topped off at 180 degrees from solar panel and heat pump (air conditioning) activity at the end of Fall, and to have most of them at 32.1 degrees at the end of the winter.

Interesting thread! What someone needs to do is establish a middle of the road model house with set heating and cooling requirements, and calculate how much water storage it would take to achieve nofossil's goal. I'd also like to see the numbers on closed(pressurized) verses open storage systems. From what I've gleaned in the few months of following this forum is that; water heat storage is necessary for optimum efficiencies in biomass fuel usage and for solar storage. But I've not seen any calculations on how much storage is necessary other than the old how deep are your pockets calculation.
 
I build a Insulted Concrete Forms (ICF) house about 10 years ago.
If I would do it again, I would incorporate a storage tank into the basement with ICF.
You can build a large volume box (>1000 gallons) for very little money. Cost all-in these days ICF runs from $12 to $15 per square foot of wall surface. This includes labor.
Then you line it with a liner and put your copper coils in and make a top cover for it. See other treads on this forum.
Now, if I really would build an other new home, i definitely would go the Passive House or Net Zero Energy way; 5 BTU/hr heating requirement or less
You probably don't need a wood boiler at all, maybe just a nice architectural indoor wood boiler with DHW capability or wood boiler stove for ambiance and/or DHW in combination with solar hot water in summer and shoulder seasons.
 
shortline said:
nofossil said:
My goal would be to have all of them topped off at 180 degrees from solar panel and heat pump (air conditioning) activity at the end of Fall, and to have most of them at 32.1 degrees at the end of the winter.

Interesting thread! What someone needs to do is establish a middle of the road model house with set heating and cooling requirements, and calculate how much water storage it would take to achieve nofossil's goal. I'd also like to see the numbers on closed(pressurized) verses open storage systems. From what I've gleaned in the few months of following this forum is that; water heat storage is necessary for optimum efficiencies in biomass fuel usage and for solar storage. But I've not seen any calculations on how much storage is necessary other than the old how deep are your pockets calculation.

While i'm waiting for 2 feet of snow to come down and an 8-year old that is very happy because there is no school today, .... here we go:

Based on a 20,000 BTU/Hr heating requirement as per Como's input

Calculation:

1000 gallons x 8.35 Lb/gallons = 8,350 Lbs of water
Let's assume a Delta T of 30 °F 8,350 x 30 = 250,500 BTU storage

We burn Red Oak, what has 8,500 BTU/Lb on a dry base.

250,000 / 8,500 = 29 lbs of red oak

Assume 20% moisture content >>> 29 x 1.2 = 34.8 Lbs

Assume 80% overall efficiency of your wood boiler >>> 34.8 Lbs x 1.2 = 42 Lbs of red oak required to keep your 1000 gallons storage tank charged

A 1000 gallons tank can store around 250,000 BTU and would bring you 250,000 / 20,000 = 12.5 hours of heat or 2 times re-fueling of your boiler per day

A 2000 gallons tank can store around 500,000 BTU and would bring you 500,000 / 20,000 = 25 hours of heat or only 1 time re-fueling of your boiler per day (depends how much wood your boiler can hold)


Please, somebody double check this calculation :cheese:
 
10 btu/sq ft is why you see a lot of European wood boiler, Viessmann for example, shown with outputs of 50,000 btu or less and only 160 gallons of storage. Nooooow it makes sense eh?
 
PassionForFire&Water; said:
shortline said:
nofossil said:
My goal would be to have all of them topped off at 180 degrees from solar panel and heat pump (air conditioning) activity at the end of Fall, and to have most of them at 32.1 degrees at the end of the winter.

Interesting thread! What someone needs to do is establish a middle of the road model house with set heating and cooling requirements, and calculate how much water storage it would take to achieve nofossil's goal. I'd also like to see the numbers on closed(pressurized) verses open storage systems. From what I've gleaned in the few months of following this forum is that; water heat storage is necessary for optimum efficiencies in biomass fuel usage and for solar storage. But I've not seen any calculations on how much storage is necessary other than the old how deep are your pockets calculation.

While i'm waiting for 2 feet of snow to come down and an 8-year old that is very happy because there is no school today, .... here we go:

Based on a 20,000 BTU/Hr heating requirement as per Como's input

Calculation:

1000 gallons x 8.35 Lb/gallons = 8,350 Lbs of water
Let's assume a Delta T of 30 °F 8,350 x 30 = 250,500 BTU storage

We burn Red Oak, what has 8,500 BTU/Lb on a dry base.

250,000 / 8,500 = 29 lbs of red oak

Assume 20% moisture content >>> 29 x 1.2 = 34.8 Lbs

Assume 80% overall efficiency of your wood boiler >>> 34.8 Lbs x 1.2 = 42 Lbs of red oak required to keep your 1000 gallons storage tank charged

A 1000 gallons tank can store around 250,000 BTU and would bring you 250,000 / 20,000 = 12.5 hours of heat or 2 times re-fueling of your boiler per day

A 2000 gallons tank can store around 500,000 BTU and would bring you 500,000 / 20,000 = 25 hours of heat or only 1 time re-fueling of your boiler per day (depends how much wood your boiler can hold)


Please, somebody double check this calculation :cheese:

My number was peak load, where I am you could probably multiply the duration by 3, in less sunny areas by 2 as the temp will vary over the course of the day.

And then it depends on how often it is your minimum temp, we have had about 4 days at -20 this year, usually 0 is a more common cold temp. So usually the storage would last a lot longer.

And then there is the solar gain, even in the fairly nasty little house we are living in at the moment, when it is above freezing and the sun is shining the heating goes off.

And finally the occupancy load, heat generated from cooking, people, dogs etc.

I would expect that in reality you might expect a once a day refill with 1000 gallons in the very worst conditions and a few times a week normally.

I might be tempted to go with smaller storage the solar could keep heated, and then kick in the wood or whatever more often when needed.
 
Exactly Heaterman; as well as the almost total absence of the 4000/5000/6000 or larger McMansion, that needs a Jesus big McHeating system, requires several very large McTruckloads of materials to build, (built thoughtlessly McWrong) here in most cases. With little or no thought to the McEnvironment it is in or its McOrientation on the property etc, etc, etc. We really have a McHuge list of what we McWaste here, then we have the McNerve to McBitch about it, not McLearn from it.

I think it was Einstein that said the definition of insanity is repeating the same thing over & over & expecting different results, if so then we are simply insane.

Kind of explains why the European's look at us the way they do. :mad: In our words I dont think they trust as far as they could throw us.

There; thats my morning rant, think I'll go split some wood.
 
PassionForFire&Water; said:
I build a Insulted Concrete Forms (ICF) house about 10 years ago.
If I would do it again, I would incorporate a storage tank into the basement with ICF.
You can build a large volume box (>1000 gallons) for very little money. Cost all-in these days ICF runs from $12 to $15 per square foot of wall surface. This includes labor.
Then you line it with a liner and put your copper coils in and make a top cover for it. See other treads on this forum.
Now, if I really would build an other new home, i definitely would go the Passive House or Net Zero Energy way; 5 BTU/hr heating requirement or less
You probably don't need a wood boiler at all, maybe just a nice architectural indoor wood boiler with DHW capability or wood boiler stove for ambiance and/or DHW in combination with solar hot water in summer and shoulder seasons.

Oh my goodness. What could you have said to them to insult them in such a way? They deserve an apology.

Sorry!! couldn't help myself. Just too good to pass up!!
 
woodsmaster said:
WEDONTNEEDNOOILLETTHEMOTHERBURN said:
well this thread has really thrown me for a loop, but as this is my first post on here i'll start by saying hello. i live in central NH and am planning on building a new house(probably around 1800 sf ranch) either this summer or the next on an 8 acre lot i just purchased. ive been reading on here for a few weeks now as i am pretty sure i want to install a wood boiler in the new house. but then i stumbled across this thread and some people are saying that in a new construction with good insulation a boiler might not be the way to go. some are suggesting a masonry heater(which i had never heard of until today) and i think someone else said a plain old wood stove would be plenty to heat a new house. as i said i dont really know much about a masonry heater but it seems to me that it would have some trouble evenly heating the entire house, especially if you dont necessarily want all your bedroom and bathroom doors open 24/7. i appreciate the fact that it requires no electricity to operate, thats a great feature, but not at the sacrifice of comfortably heating the ENTIRE living space. and what is the price of having something like that installed? i checked out the link with the masonry boiler, pretty cool idea, but is it a realistic option to heat my house? and how hard would it be to find someone that could install something like that? someone also said that a wood boiler is good for a house designed around fossil fuel but if you are building new you may want to look at going other directions, but arent i going to want some kind of backup system anyways like an oil burner incase i want to take a vaca in the winter or get injured and cant do the wood thing for a while? i feel more confused now than i was before i came here lol please straighten me out!

If I was building new and had access to natural gas I would super insulate, then put in radiant floor and a condensing boiler and forget about the wood. the $8,000 or so you save will buy a lot of gas. Just my 2cents.


well im pretty sure i want wood to be my main source of heat as it is free and i enjoy producing it. but maybe what youre saying is that id be better off with a simple wood stove than a wood boiler or a masonry heater due to installation price. would a wood stove in the basement act the same as radiant floor heating? i feel like a wood stove on the first floor would be overkill and the place would be 90 degrees before i knew it.
 
Answering the construction question first will enable you to make intelligent decisions about your heating/cooling needs. If it's 1800 sq ft and standard stick built construction then a wood boiler may be a good choice. Especially if you may add on or build additional garages, polebarns or whatever in the future.
If on the other hand you take some steps to build a very tight well insulated home, that wood stove in the basement may be a very good suggestion for you to consider. The only thing you would lose is the ability to heat your domestic hot water.

So. Are we going 2x4 stick built walls? 2x6? 2x6 + an inch of foam on the outside? ICF? That's what you need to answer before the wood boiler/wood stove/gas boiler question.
 
well i honestly dont know much about building a house. what is the price comparison when you look at either building a normally constructed house with a wood boiler vs. a very well insulated house with a cheaper heating system?
 
WEDONTNEEDNOOILLETTHEMOTHERBURN said:
well i honestly dont know much about building a house. what is the price comparison when you look at either building a normally constructed house with a wood boiler vs. a very well insulated house with a cheaper heating system?

You would need to define both those terms for a start, factor in your heat loads and location, take into account re sale value and your time costs in producing and feeding the boilers. And of course your local construction costs.

I am going the wood boiler route as in my building I do not really have any other options. For a new build it is really a no brainer, avoid the issue, build a better house that would be more comfortable and nicer to live in.
 
WEDONTNEEDNOOILLETTHEMOTHERBURN said:
well i honestly dont know much about building a house. what is the price comparison when you look at either building a normally constructed house with a wood boiler vs. a very well insulated house with a cheaper heating system?

If I were building new right now I would build "superinsulated" and then choose the heating method that suits the design, even if I were burning wood. I have an EKO 25 in my basement that runs fewer hours each year because of the ongoing improvements in the insulation in my home. I admit that the improvements are a hobby for me because I enjoy doing the work and seeing the positive results. I don't know your age but if you're going to burn wood, something to think about is how are you going to handle 4 or 5 cords a year when you are in your seventies. I'll be 69 in April and I can tell you that 3 cords are as much I care to handle a year.

The other thing is comfort. People that don't live in a well insulated home don't understand that the comfort temperatures are very uniform in a house like mine. I don't have any friends, acquaintances or relatives that could care less about energy conservation and comfort is on the back burner. When I visit their homes, I can't wait to get out of there and get home where it's comfortable. Someone in an above post worried about having a warm spot and cooler or cold temps whit a masonry heater. I can tell you that in a superinsulated house you will still be comfortable in the far reaches of a home. I fire my EKO once a day to replenish my storage. I usually start my fire at 4:00 pm and my burn usually lasts 'til 9:00 pm depending on whether the zones are calling for heat at the time. The master switch on the boiler is then shut off. I haven't had a fire overnight since the winter of 2008-2009.
 
100% solar fraction homes and buildings have been constructed in Europe. This Swiss company manufacturers tanks for thermal storage and features a 100% solar thermal project in Switzerland. Click on the English site then scroll down to the 100% solar apartment building to get an idea of tank size for 100% solar fraction.


http://www.jenni.ch/
 
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