- Thread starter
- #21
My husband is saying the same thing. We have a great supply of wood and it does seem like a stinking conspiracy. Ha.
Foam insulation vs blown in (1 Viewer)
- Thread starter Jupiter Judy
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You have touched on an interesting topic, that can get very involved. I wrestled with the same issues when building my home a few years ago. I did the entire project myself, so I spent many hours learning how to figure all this stuff out. I was also shocked by the cost of the high efficiency stoves.
You have to start with total overall heating and cooling conditions for your home. I'm in NW Colorado so my heating demands are far higher than yours. There are complex calculators and such out there, but what you have to find is the design outdoor heating temp your area. It is not the max low, but the average low for heating. For my location that was 4F, but the max ever recorded was -40+F, but if you size your heating equipment to the max it will be oversized. You mentioned central heating, what is supplying the fuel for that? Propane or electric? The HVAC guys doing that system can tell you what the heat load will be for your home, but the insulation issue should have been settled before anyone designed these systems for your home, otherwise they are just using rules of thumb and basic numbers. What about cooling load, are you cooling the home too with the central system, are you doing swamp coolers, something else? I would see that as a more important system than heating in North Texas. Also what are the bare minimum insulation codes for your building zone?
What I'm getting at is there is alot to consider, the stove guys are full of crap, and I don't know if your builder is totally up to speed. I can only tell you the conclusion I came too. I wanted radiant heat in my home, quiet, comfortable and can be supplemented with solar thermal panels. But we built our home out of pocket, so budget was very important, however, 5 years later, I wish I had ponied up the extra 20K and did the radiant through the entire home like I dreamed. In any case, I too looked at a high efficiency fireplace, and cost was an issue, and if you have this expensive central heating, why buy another expensive heating appliance that you have to gather wood for and screw around building a fire. I felt as though the novelty of the warm fire place would wear off pretty quickly and then it would it would just be there and the convenience of kicking up the thermostat when go get home late from work and such would win out.
My home is one story ranch style, 1700 sqft, with a 1500 sqft walkout basement, 2100 sqft with the attached garage. I did Corebond spray foam in the exterior 2x4 walls, which barley met my building code, (R21) but I didn't want to do 2x6 walls. I put 2 layers of fiberglass in the ceiling to get R68, since that is your most heat loss. Basement slab has R10 2" DOW board under it, and cement walls of basement have R13 fiberglass on them. Careful sealing and housewrapping with Marvin windows. The envelope of the home is tight, the overall R value of the home is very good. Sealing is so good we get some window condensation problems in -15F and below nights and extended cold spells. I did put in an exchanger that is supposed to move in fresh air, but we don't run it continuously, usually just as needed, but it has never solved the condensation, it never kicks on with the humidistat in the winter as our home runs in the 30's for humidity most the year, it is dry here.
Ultimately I did electric for the whole house, I too did not want to hassle with propane any longer. I put radiant heat in the basement slab, I have since added solar thermal to that system, 240 sqft to be exact (big solar), as well as the domestic hot water tank. I see about $100 dollars in savings on the electric bill in the winter. I did some electric heat backup in the main level, and we use it slightly through the winter. My ultimate compromise on the central vs fireplace decision was a pellet stove. We heat the entire main level with the pellet stove, average 1 bag of pellets per day during the bulk of winter, cold snaps force 2 bags through. It is automatic as long as it has pellets and everything is working, it has a pleasant fire to stare at, and it has been economical from a fuel standpoint. It has an outside air kit for combustion air. Pellet stove is rated at 60K BTU, does alright most nights.
Over a winter we burn 2 tons of pellets at roughly 250$ a ton the past couple of years (they keep going up in price) and about $150 extra per month on the electric bill for about 5-6 months, that works out to pretty affordable heat for the square footage and our climate and we stay comfortable. Compare that to the 1000 gallons of propane we burned a year in our single wide trailer at average $2 a gallon at the time, nearly half the cost for 3 times the space. I also added a minisplit AC/Heat system year before last, as the supertight home was building and holding heat in the summer, it was like a flywheel effect and we just could not get it cooled off at night. We have enjoyed that system, and summer power consumption has been minimal on it thus far and it is really nice for shoulder season heating demands, but is not usable most of the winter due to our low overnight temps, they have a limit of operation for producing heat in the winter.
If I were you, consider the needed insulation code, how much over that you want to go, how tight do you really want or need your house, and pick an insulation. From there you can figure if you want this stove to heat the entire home regularly, or do just want comfort heat in the evenings for the main rooms. The solutions presented on one-way air vents for the house would be more than adequate to cover the combustion of about any stove, and if you go for a true high efficiency wall insert, they should be used with an outside air kit, period, it just makes good sense, and should come that way. Or just get a small one or freestanding with some sort of wall vent and build a fire on cold nights. If you want foam than do it in all the walls. Insulate the home the way it should be, the appliances should be installed assuming the house is tight no matter what, this can be fixed, the stove guys are being lazy.
You have to start with total overall heating and cooling conditions for your home. I'm in NW Colorado so my heating demands are far higher than yours. There are complex calculators and such out there, but what you have to find is the design outdoor heating temp your area. It is not the max low, but the average low for heating. For my location that was 4F, but the max ever recorded was -40+F, but if you size your heating equipment to the max it will be oversized. You mentioned central heating, what is supplying the fuel for that? Propane or electric? The HVAC guys doing that system can tell you what the heat load will be for your home, but the insulation issue should have been settled before anyone designed these systems for your home, otherwise they are just using rules of thumb and basic numbers. What about cooling load, are you cooling the home too with the central system, are you doing swamp coolers, something else? I would see that as a more important system than heating in North Texas. Also what are the bare minimum insulation codes for your building zone?
What I'm getting at is there is alot to consider, the stove guys are full of crap, and I don't know if your builder is totally up to speed. I can only tell you the conclusion I came too. I wanted radiant heat in my home, quiet, comfortable and can be supplemented with solar thermal panels. But we built our home out of pocket, so budget was very important, however, 5 years later, I wish I had ponied up the extra 20K and did the radiant through the entire home like I dreamed. In any case, I too looked at a high efficiency fireplace, and cost was an issue, and if you have this expensive central heating, why buy another expensive heating appliance that you have to gather wood for and screw around building a fire. I felt as though the novelty of the warm fire place would wear off pretty quickly and then it would it would just be there and the convenience of kicking up the thermostat when go get home late from work and such would win out.
My home is one story ranch style, 1700 sqft, with a 1500 sqft walkout basement, 2100 sqft with the attached garage. I did Corebond spray foam in the exterior 2x4 walls, which barley met my building code, (R21) but I didn't want to do 2x6 walls. I put 2 layers of fiberglass in the ceiling to get R68, since that is your most heat loss. Basement slab has R10 2" DOW board under it, and cement walls of basement have R13 fiberglass on them. Careful sealing and housewrapping with Marvin windows. The envelope of the home is tight, the overall R value of the home is very good. Sealing is so good we get some window condensation problems in -15F and below nights and extended cold spells. I did put in an exchanger that is supposed to move in fresh air, but we don't run it continuously, usually just as needed, but it has never solved the condensation, it never kicks on with the humidistat in the winter as our home runs in the 30's for humidity most the year, it is dry here.
Ultimately I did electric for the whole house, I too did not want to hassle with propane any longer. I put radiant heat in the basement slab, I have since added solar thermal to that system, 240 sqft to be exact (big solar), as well as the domestic hot water tank. I see about $100 dollars in savings on the electric bill in the winter. I did some electric heat backup in the main level, and we use it slightly through the winter. My ultimate compromise on the central vs fireplace decision was a pellet stove. We heat the entire main level with the pellet stove, average 1 bag of pellets per day during the bulk of winter, cold snaps force 2 bags through. It is automatic as long as it has pellets and everything is working, it has a pleasant fire to stare at, and it has been economical from a fuel standpoint. It has an outside air kit for combustion air. Pellet stove is rated at 60K BTU, does alright most nights.
Over a winter we burn 2 tons of pellets at roughly 250$ a ton the past couple of years (they keep going up in price) and about $150 extra per month on the electric bill for about 5-6 months, that works out to pretty affordable heat for the square footage and our climate and we stay comfortable. Compare that to the 1000 gallons of propane we burned a year in our single wide trailer at average $2 a gallon at the time, nearly half the cost for 3 times the space. I also added a minisplit AC/Heat system year before last, as the supertight home was building and holding heat in the summer, it was like a flywheel effect and we just could not get it cooled off at night. We have enjoyed that system, and summer power consumption has been minimal on it thus far and it is really nice for shoulder season heating demands, but is not usable most of the winter due to our low overnight temps, they have a limit of operation for producing heat in the winter.
If I were you, consider the needed insulation code, how much over that you want to go, how tight do you really want or need your house, and pick an insulation. From there you can figure if you want this stove to heat the entire home regularly, or do just want comfort heat in the evenings for the main rooms. The solutions presented on one-way air vents for the house would be more than adequate to cover the combustion of about any stove, and if you go for a true high efficiency wall insert, they should be used with an outside air kit, period, it just makes good sense, and should come that way. Or just get a small one or freestanding with some sort of wall vent and build a fire on cold nights. If you want foam than do it in all the walls. Insulate the home the way it should be, the appliances should be installed assuming the house is tight no matter what, this can be fixed, the stove guys are being lazy.
- Thread starter
- #23
We decided on Northstar from Heat N Glo. Not using foam insulation. The fireplace is more important to us than a super tight house.
That stove appears to have a combustion air intake, so house tightness becomes irrelevant. Should heat the home just fine in your climate, should have plenty of output unless you are doing crazy amounts of windows or high ceilings.
I have found on my home that I'm a little too airtight. The new building methods and tight envelopes is nice, but sometimes older homes performed just fine and did not have the moisture and mold issues that some newer homes are having because they breath naturally.
Looks like it should all work out.
I have found on my home that I'm a little too airtight. The new building methods and tight envelopes is nice, but sometimes older homes performed just fine and did not have the moisture and mold issues that some newer homes are having because they breath naturally.
Looks like it should all work out.
- Thread starter
- #25
I wonder if ten or twenty years down the road we’ll be hearing about all the side effects of foam insulation. My mother reminded me years ago that margarine was supposedly healthier than butter. Well we know that was proven incorrect after a few years. Lol. Anyway I’m sticking with a wood burning fp. It just seems more natural. What can I say.
It should be lovely, I think those high efficiency ones are the way to go. That one even has the option of ducting warm air to other rooms, that would make heat distribution very even in the dwelling. Biggest drawback is the cost.
Who knows on the foam, I made the best choice I could at the time, it was done in a day, and I was stuck with it as I couldn't get the required R21 wall insulation for my climate zone with fiberglass in a 2x4 wall. So far it has been fine, there was no odor after it cured, and it took me another 8 months to finish the house before we moved in, so hopefully everything vented out pretty good. Carpet seemed to linger the longest after moving in. There were some real misses with the foam insulation, some did break down early on and others did not provide the proper insulation. I think you would have to just blow the house up before you remove it. Would have to strip all the exterior walls, and then the stuff is sprayed in and expands, once cured you can't hardly chip it off stuff.
Who knows on the foam, I made the best choice I could at the time, it was done in a day, and I was stuck with it as I couldn't get the required R21 wall insulation for my climate zone with fiberglass in a 2x4 wall. So far it has been fine, there was no odor after it cured, and it took me another 8 months to finish the house before we moved in, so hopefully everything vented out pretty good. Carpet seemed to linger the longest after moving in. There were some real misses with the foam insulation, some did break down early on and others did not provide the proper insulation. I think you would have to just blow the house up before you remove it. Would have to strip all the exterior walls, and then the stuff is sprayed in and expands, once cured you can't hardly chip it off stuff.
Spray-in foam is excellent. if you build your house like a termite mound in Africa then you won't need air conditioning. An architect use that concept and design to build buildings similar to that tent termite Mound and the cooling efficiency was incredible
Little late to the game but here it goes.
We build homes here in BC to a five step code for the Building code.
One being the lowest and five the highest.
The whole idea of building an energy efficient home has to do with insulation done right, lots of it, no thermal bridges and
air tight. All homes in BC have to have a midstage blower door test and one upon completion of home.
The less the air leaks the less heat is required.
Insulation is very important, more the better. The type is up to how deep your shovel can reach into your wallet.
All the homes we build, we use rigid foam, or 2lbs closed cell.
If we build wood frame then opencell with a 2" blanket of comfort board then rain screen and exterior finish.
Like using Siga for the exterior to make the house air tight along with their various products to achieve a high level of air tightness.
We achieve a 0.7 for airtightness on typical home using above method.
Now, using a wood burning fireplace is no problem provided that combustion air is brought directly into the fireplace. This way
it doesn't require the heated air in the house to be used to "go up the chimney in an air tight house.
Have used a Waltherm gasification fireplace with great success in an off grid application.
Waltherm has a water jacket so you can get hotwater for domestic use and for heating.
Using an ERV or an HRV in an airtight house is a must and is part of our BC Building code.
Been using HRV in our homes for over 28 years.
Hope this helps and good luck with the build.
We build homes here in BC to a five step code for the Building code.
One being the lowest and five the highest.
The whole idea of building an energy efficient home has to do with insulation done right, lots of it, no thermal bridges and
air tight. All homes in BC have to have a midstage blower door test and one upon completion of home.
The less the air leaks the less heat is required.
Insulation is very important, more the better. The type is up to how deep your shovel can reach into your wallet.
All the homes we build, we use rigid foam, or 2lbs closed cell.
If we build wood frame then opencell with a 2" blanket of comfort board then rain screen and exterior finish.
Like using Siga for the exterior to make the house air tight along with their various products to achieve a high level of air tightness.
We achieve a 0.7 for airtightness on typical home using above method.
Now, using a wood burning fireplace is no problem provided that combustion air is brought directly into the fireplace. This way
it doesn't require the heated air in the house to be used to "go up the chimney in an air tight house.
Have used a Waltherm gasification fireplace with great success in an off grid application.
Waltherm has a water jacket so you can get hotwater for domestic use and for heating.
Using an ERV or an HRV in an airtight house is a must and is part of our BC Building code.
Been using HRV in our homes for over 28 years.
Hope this helps and good luck with the build.
This is excellent Zone 6 and 7 building methods. Put rigid foam on the outside!! It's finally in the code here for Zone 6. We *finally* got air leakage tests required here, but they relaxed the rule to allow ACH rate of 7 (50 Pa) which is stupid. One step forward, then another step back in progress.
I personally would never use wood heat as a primary source. I've done it, and it sounds all romantic, cutting your own wood, splitting, living off the land, blah blah blah. Then the next year it becomes an incredible chore. Not to mention dealing with all the ashes, the soot inside the house, the stink to get it going, carrying it in all the time... ya I'm done with that. Maybe a backup if the power goes out, or you wanna "get in the mood".
If I were building new, it would be ground source heat pump, with a HRV system. No fuss, low maintenance, they're nice and quiet, and you just need to push that switch on the wall. Put a head in each room.
Putting rigid foam on the outside of a new home has been banned by Home Warranty Providers here in BC We are in coastal marine zone 4. Every home in BC has to have a 2/5/10 year warranty. Reason rigid closed cell foam has been banned here is because it isn't permeable . If you build using wood frame construction and you do not make the VP absolutely air tight the indoor moisture being warm will condensate on the ply/plates studs. The exterior air barrier and exterior insulation must be vapor permeable.
All homes in BC have to have a midstage blower door test performed by a third party firm. Insulation, vb install and exterior air barrier, insulation and cladding completed prior to test being performed. Last house we had tested we had .75 air exchanges.
If you were building new... If I were building new and I'm on grid then yes to air to air heatpump.
Have installed 4 ground source heat pumps, one a horizontal loop field the others were drilled.
The geothermal cost difference vs air is to large to say it's cost effective in my opinion.
Also all new build homes in BC have to have an HRV per BC Building code, we have been installing HRVs in all homes since 1990.
We are building our retirement home on an Island which is off grid, boat access only.
Wood if it is seasoned properly and burned in a kaechel offen or in a Waltherm you will need to clean ashes maybe once or twice a year. Have 42x42 Rumford fireplace in our home in N. Van, it required cleaning once a year.
We do not plan on using dino fuel for our off grid island home. We pay a carbon tax on fuels that are purchased not sure if in the states you pay carbon tax. In Europe if you use firewood or wood pellets the the governments gives you a tax break / carbon credits for not using dino fuels. Besides trees grow every day in our forest.
Build the house airtight, use lots of insulation and good guy glass and you can heat your home with two light bulbs and a fart.
All homes in BC have to have a midstage blower door test performed by a third party firm. Insulation, vb install and exterior air barrier, insulation and cladding completed prior to test being performed. Last house we had tested we had .75 air exchanges.
If you were building new... If I were building new and I'm on grid then yes to air to air heatpump.
Have installed 4 ground source heat pumps, one a horizontal loop field the others were drilled.
The geothermal cost difference vs air is to large to say it's cost effective in my opinion.
Also all new build homes in BC have to have an HRV per BC Building code, we have been installing HRVs in all homes since 1990.
We are building our retirement home on an Island which is off grid, boat access only.
Wood if it is seasoned properly and burned in a kaechel offen or in a Waltherm you will need to clean ashes maybe once or twice a year. Have 42x42 Rumford fireplace in our home in N. Van, it required cleaning once a year.
We do not plan on using dino fuel for our off grid island home. We pay a carbon tax on fuels that are purchased not sure if in the states you pay carbon tax. In Europe if you use firewood or wood pellets the the governments gives you a tax break / carbon credits for not using dino fuels. Besides trees grow every day in our forest.
Build the house airtight, use lots of insulation and good guy glass and you can heat your home with two light bulbs and a fart.
1911
chupacabra
Not yet thank goodness, but it's probably coming some day, the way things are going.
