# Super insulating a new house?



## Randy Rooster (Dec 14, 2004)

I am getting ready to build a new place- dont know exactly yet whether I am going to use 2x6 stick built walls or an insulated concrete form, but wondering if I go with the 2x wall some suggesstions for having a place that is extremely well insulated. Im going to heat and cool with a heat pump, but electric is still expensive in my area so I want to get that bill down as far as possible. I think I would use blown cellulose in the walls. Would it pay to then put some of that sheet styrofoam over the studs on the inside or outside? What about under the floor joists and in the attic? I have heard that sprayed foam directly over the inside of the roof sheathing is the best for the attic. Just wondering if anyone else has done any of these and how it has worked out.


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## joken (Dec 25, 2005)

I have never heard of insulating the roof sheathing except for open beam ceilings. Do you not vent the attic then? Seems like you would just be heating unoccupied space. Bat insulation in the walls has a higher R-value than blown in. I think? you can get R-23 bats for a 6" wall. If your house is too tight your exhaust fans won't work and you will have humidity issues. Maybe introduce some outside air on the return side of the heat pump. Put a damper in it so you can adjust it to the minimum required. I am a heating guy and have seen insulated crawl spaces with a rat slab. Last house I built was on slab with the ductwork ran thru a soffit between up and downstairs. This eliminated all duct heat loss/gain and made it easy to heat both floors.Good luck, Ken


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## MartyPalange (Jan 10, 2003)

When we built our home 20 years ago we used double wall construction. Exterior 2x4 wall that is load bearing, 1" space, then interior 2x4 wall. The wall studs need to be offset since the weak point in the wall insulation barrier is the wood stud. We used tyvek (wind barrier) on the outside and sheet plastic (vapor barrier) on the inside under the drywall. We heat with a woodstove @3 cords in CT. No air conditioning. This may be more than you need in North Carolina. At the time we wanted to avoid rigid insulation. Most people today use 2x6 walls with rigid insulation on the exterior to achieve the same R value. As a side note, if you super insulate your home, you may need an air to air exchanger. Here in CT, the utility company is a good source of information.


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## GREENCOUNTYPETE (Jul 25, 2006)

I know a fammily from church that built thier home in the late 80's and super insilated it here in south central wisconsin.
they did a 2x4 outer wall and a 2x4 inner wall the outside to inside measure was 16 inches they filled this with fiberglass insulation and double wrapped with 3 mill plastic inside and out also they put all the outlets in the floor and lights on the second floor were all wall sconces on interior walls basicaly they never punctured the walls or second floor ceiling the outside of the house was a stained cedar siding and all windows were the best thermal pains they could reasonably get it is built into a hill about 5 feet up the north side and large windows on to the south they say they never go over 35 dollars a month heating or cooling heat is a simple forced air natural gas system air is furnace mounted central air and they have a small wood stove that they run ocationaly but they say that unless it is very cold the stove raises the house temp to 80 in a hurry
and it is a fairly large 4 bed house 2200 to 2400 square feet would be my guess

i heard somplace r35 in the walls r40 in the attic is the point at wich more insulation has little effect 

hope this helps


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## SolarGary (Sep 8, 2005)

Hi,

For the 2X6 stud walls (on 24 inch centers -- not 16), the insulated sheathing goes on the outside to reduce the thermal bridging through the studs. Some don't like the insulated sheathing in that it does not have the strength of plywood or OSB sheathing, and this might be a consideration if you live in a high wind or earthquake area. Having something like the insulated sheathing (or the techniques listed below) to break the thermal brdiging by the studs is very important. Here is a calculator that will show you how much the thermal bridging hurts on otherwise well insulated walls:
http://www.builditsolar.com/References/energysimsrs.htm#Walls

A coupe other wall thoughts:
Some of the builders around here are using 2X6 studs, then spraying an about 2 inch thick layer of the polyurethane foam, and then using bat insullation to fill the rest of the cavity. The foam gives bombproof air infiltration protection, and only using 2 inches keeps the cost down.

I think that the wall construction used by Gimmie Shelter (and the similar Mooney wall) offer really good insulation and low thermal bridging at a good cost.
http://www.builditsolar.com/Projects/SolarHomes/constructionps.htm#Stick
These guys have worked out a whole wall construction that is high R, low thermal bridging, and low infiltration -- its worth a careful read.
http://www.builditsolar.com/Projects/Conservation/MooneyWall/MooneyWall.htm

SIPS
SIPS are good of you have a builder who is familar with them -- good insulation and tight.

ICFs
If you go the ICF route, there is an advantage to using the type that has the insulation on the outside and the concrete on the inside. This keeps the thermal mass inside the insulation where it can do some good.
Like the Dow T Mass and some of the other here:
http://www.builditsolar.com/Projects/SolarHomes/constructionps.htm#ICF

Strawbales are good to -- lots of insulation, tight, built in thermal mass, and easy on the planet.

---
If the house is well insulated, then air infiltration becomes the big heat loss, so this is worth really paying attention to. Some types of construction (like SIPS and ICF) are naturally pretty tight, while others can be, but it requires really careful attention to detail throughout the construction. 
http://www.builditsolar.com/Projects/SolarHomes/constructionps.htm#Best

On the inulsulated roof deck. This is a somewhat new development in which the attic becomes part of the conditioned space, and is not vented to the outside. I know there is a house on my site that uses this, but I can't seem to find it now -- I think if you Google around for it you will find something. I think it may be a good idea if excuted well.

-- 
heat pumps:
I know people are very up on heat pumps, and you can feel free to ignore my negative thoughts on them 
I don't care that much for heat pumps in that while they use electricity very efficiently, most of that electricity is generated at very inefficient coal fired power plants. These power plants generate 4 times as much greenhouse gas per BTU of energy produced as a modern gas furnace. A heat pump with a COP of 3 or so still leaves you generating more greenhouse gas than a good gas furnace would. If it were me, I'd spend the money on very good insulation and infiltration control, and try to use passive solar and maybe active solar -- these technolgies have no greenhouse gas penelty.

On the cooling front, in addition to the good insulation and low infiltration, you want to really control unwanted solar gain with overhangs or the right kind of glass.

Good Luck!

Gary


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## gccrook (Nov 21, 2003)

We used standard 2X construction, but with scissor trusses for a cathedral ceiling. We had the Icynene sprayed on foam, and they sprayed it on the roof decking. If I did not have cathedral ceilings, I would not have sprayed it on the roof decking. It is only 3.5 inches thick, which gives an R value of around 13, but it feels much better than that, because it eliminates all air infiltration where it is sprayed. It is also very quiet in there now.


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## Jackpine Savage (Jul 4, 2002)

This site has some good information on insulation and vapor barrier strategies for different parts of the country: http://www.buildingscience.com/

Make sure you include an air exchanger in your plans.


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## Randy Rooster (Dec 14, 2004)

Thanks to every one for the help. If I use the additional 1/2 or 1" foam sheathing over my plywood sheething it adds about 2 and 4 r values. I am curious if anyone knows how to figure what that extra r value means in heating/cooling costs reduction - how long would it take to pa back the extra cost?


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## SolarGary (Sep 8, 2005)

Hi,

On figuring the value of adding the outside foam:

If you go to the "whole wall" calculator mentioned above
http://www.ornl.gov/sci/roofs+walls/AWT/InteractiveCalculators/NS/SimCalc.htm
It gives a real (whole wall) R value of 14.1 for 2X6 24 OC with no foam on the outside. With 1 inch foam it gives R18.35

If you take these to my Insulation Upgrade calculator:
http://www.builditsolar.com/References/Calculators/InsulUpgrd/InsulUpgrade.htm
And put in an area of 32 sqft (one sheet), 8000 deg-day climate, and Propane fuel at $2 per gallon, it gives:

First year saving = $2.74 per sheet of foam board.
10 year saving with 10% fuel price inflation per year = $43.71 per sheet.

I guess that one sheet of 1 inch thick foam in builder quantities might be $12 per sheet?

So, not counting install labor, it pays back a (2.74/12) = 22% return, with a simple payback period of about (12/2.74) = 4.3 years -- less if fuel goes up.
One way to look at it is that you can borrow the mortgage money to do it, and save more money each year than the interest on the extra mortgage money.

It probably also gives you a little bit tighter a house. 

It also reduces green house gas emissions by 18 lbs per year for each sheet of foam board.

Looks like a deal to me  Remember, this house is going to be burning fuel and making greenhouse gases a hundred years from now.

Note that if you live in a less than 8000 deg-day climate, or use cheaper fuel, it takes longer.

Gary

Gary


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## CatsPaw (Jun 16, 2006)

Meaning no offense to any of the responders here, I have yet to see an explaination on insulation yet that I believe. I say this because I've seen yeas and nays from trades and homeowners. There is always some factor that is not taken into account. And really I think it would take an accountant and some hard pricing to figure it out.

Also, I will state that I don't know the answer! These are some of the things that make me wonder (or...Things that make you go...hhmmmm.)

Somewhere, I read from an insulation industry source, based on some 20 year study, that 2 x 6 walls were not cost effective, based on savings, increased cost of materials and such. Fuel prices were alot cheaper then too.

Next The last time I priced spray foam insulation about 6 months ago, for an 1800 sq.ft. house would be about $9000 compared to $1200 for standard, in a 2 x 4 framed house.

Also borrowing for the increased cost of the super insulation is probably a real bad idea if you're looking at return on your investment. This is based on what I perceive as a major extra expense (as in, extra framing, extra insulation or spray foam all running maybe an extra $10K-$20K depending on the size of the house.) Mortgages are amortized. Meaning a straight return on cost doesn't work since the increase in monthly payment is almost all interest, like 95%-99% in the early years. You can at least deduct it, but that means you're only shelling out 70% or 75% instead of 100% of the extra cost from borrowed money. Pay out 70%-75% vs. 22% return = 48%-53% on the negative. I think most people don't realize what they actually pay for their house over the life of the loan. Check your mortgage out. There will be a figure that is the sum total of all the payments. Compare it to the purchase price. (One lender trick is to say "Hey, it'll only increase your monthly payment by $20... which adds up to a huge amount over the life of the loan.)

As far as the environment, think of the v.o.c.'s from that spray foam and where the chemicals come from in the first place (petroleum), the extra trees for the extra framing. Probably though less over the life of the product compared to what is burned in fuel. (there is a campaign stop stop logging around here, but, I'm not a tree hugger....being a carpenter and all.)

Air handlers, the last I heard, could run an extra $2000-$4000 (I think this was on a fairly large house....maybe 3000 sq.ft.) You will HAVE to have one if you make the house really tight. Between various unseen molds and v.o.c.s and cooking fumes and other things, indoor pollution is becoming a real topic.

Any way just some thoughts. Maybe some day I'll actually know the answer.


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## Randy Rooster (Dec 14, 2004)

CP- thank you for your questions- it is always good to hear other perspectives, but most of the items you brought up dont apply to my situation. They may be more meaningful to othewrs readingthis thread and contemplating doing this type of insulating.

The primary reason I am choosing to use 2x6 construction is the strength of the materials. Not only will yellow pine 2x6 make for much stronger walls, but yellow pine is stronger than spruce/pine fir lumber of an equal dimension. The extra insulation value of 5 1/2 inch cavity over a 3 1/2 inch one is a bonus. In my area yellow pine is much cheaper than spf. So much so that a 2x6 of stud length is cheaper than a 2x4 of the same length that is spf. I may have to pick through the yellow pine a bit more, but it is still cheaper than 2x4. Yellow pine is also local grown, and sawn. It doesnt need to be shipped 1000 miles from canada like the spf lumber. I am not planning on using spray foams- I will use blown cellulose and probably rigid foam insulation sheets on the outside of the walls. In my area air conditioning is a must for 3-4 months of the year. Electricity to run that a/c is very expensive.

I will also be paying for my materials as I go. No mortgage for me. I was lucky enough to have sold my home when the real estate market in my area hit its peak and I made a bundle of money- more than enough to purchase the materials for me to build my new place.


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## Randy Rooster (Dec 14, 2004)

Gary-

I used your calculator and found that I would save $196 a year from heating savings alone, by adding an r-4 insulation. In my area cooling is just as important if not more so than heating for 3-4 months a year, so I am guessing conservatively to be able to save $400 a year by adding the rigid insulation. I think it will be well worth it. Thank you.

Do you have any plans to upgrade you caluculator to take cooling into account?


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## SolarGary (Sep 8, 2005)

Randy Rooster said:


> Gary-
> 
> I used your calculator and found that I would save $196 a year from heating savings alone, by adding an r-4 insulation. In my area cooling is just as important if not more so than heating for 3-4 months a year, so I am guessing conservatively to be able to save $400 a year by adding the rigid insulation. I think it will be well worth it. Thank you.
> 
> Do you have any plans to upgrade you caluculator to take cooling into account?


Hi Randy,

One caution about my Insulation Calculator is that tends to overestimate the heating bill savings in warmer climates. This is because it does not account for the heat that comes from internal sources (like bodies and appliances), and these contribute a greater percentage of the heat in a warmer climate. I have not done anything about this yet, because, as you say, the insulation helps on cooling as well as heating. This is a long way of saying I think that $400 may be a little on the high side. But, even if its only $300 -- thats pretty darn good!

I would like to upgrade the calculator to take into account both cooling savings and internal loads. But, I think its going to have to be after Christmas.

Gary


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## fantasymaker (Aug 28, 2005)

Randy Rooster said:


> . In my area yellow pine is much cheaper than spf. So much so that a 2x6 of stud length is cheaper than a 2x4 of the same length that is spf. I may have to pick through the yellow pine a bit more, but it is still cheaper than 2x4. QUOTE]
> Could you get yellow pine 2x4s
> Its been a few years back that I worked in a lumber yard and was asked to calculatethe cost diference between 2x4 2x6 and double 2x6 walls at that time using 2x4 was the cheapest but double 2x4 was about 15% cheaper than 2x6! and only about 300 more on a 2400sf house than single 2x4!


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## Randy Rooster (Dec 14, 2004)

FM-

For some reason it is next to impossible to get syp 2x 4's round here.


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## agmantoo (May 23, 2003)

Randy, I too live in NC. I have 2x6 studs with the external sheet insulation. Two things that give me a good return are the windows and the geothermal heatpump that I have. I have Hurd windows designed for the south, there is a plastic film between the two panes of glass. The film reflects to almost eliminates the solar gain to reduce cooling expenses. The geothermal heat pump is the key to low utility bills. In the summer it just loafs since the water coming to the unit is around 56 degrees and the house thermostat is around 76 degrees. In the winter the heatpump has to work a bit harder to extract from the 56 degree water enough heat to bring the house to 70 degrees. No backup (strip) heat is required since the heatpump works as if the exterior temp is 56 year around. The efficiency holds regardless of the weather.


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## Burbsteader (Aug 6, 2002)

I can't tell you specific savings and I do not have first hand experience with blown insulation.
What I can tell you is that we have bat insulation in the walls, up in the attic and shortly after moving in, under the floor joists.
A lot of people overlook the floor and I think it is a big mistake. (I also recommend using foundation vent covers and quilted window treatments in the winter)

When we did ours, we noticed an immediate temperature difference. DH put in about half of the living room floor, then came in to the living room and took temperature readings. 
There was an immediate 5 degree difference between the insulated and non insulated floor. If I remember correctly, it climbed closer to 10 degrees or so difference as the day went by.

Can't give specific savings, as we live in the PNW. But I can tell you that we do not have the heat running yet and it is comfortable. When the outside temps dropped into the 30s it was a little chilly in the morning, but not cold.


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## ET1 SS (Oct 22, 2005)

CatsPaw said:


> ... Next The last time I priced spray foam insulation about 6 months ago, for an 1800 sq.ft. house would be about $9000 compared to $1200 for standard, in a 2 x 4 framed house. ...


Today, I just finished spraying our new house with foam.

I still have a bit left in the tanks so tomorrow I will spray on a second layer on one wall, but the entire house [walls and roof] have a 2 inch coating of hard styrofoam epoxy on, as of now.

It cost us $4950.

Using Dow's Froth-paks, well okay actually I found a cheaper competitor that market's the same thing as 'touch-n-seal' but if you want to google it, try the froth-pak, as that is what everyone calls it.

Our house is 2400 square foot with 14 foot cathedral ceilings. 60 foot long by 40 foot wide, with 12 foot eaves and a 14 foot peak. I sprayed the entire ceiling [roof] and walls [except for the doors and windows].

Our house is a steel building. Much cheaper than stick, and no thermal-bridging.

I did not really learn the 'tricks' of doing it right and getting the foam to work the best until I was on the last couple of tanks though.

LOL

Good luck.


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## ET1 SS (Oct 22, 2005)

CatsPaw said:


> ... You will HAVE to have one if you make the house really tight. Between various unseen molds and v.o.c.s and cooking fumes and other things, indoor pollution is becoming a real topic ...


A really tight house?

Have you ever seen a foamed house? The walls are totally sealed, no air drafts anywhere.

V.O.C.s Do you mean like from back in the 1960s and 1970's? Wow, I don't think that you can even buy that old stuff anymore.

This stuff is compressed in nitrogen. It does outgass, it outgasses nitrogen.

The two chemicals mix in the nozzle and form an epoxy, they heat to over 200 degrees, and spray out onto the wall or ceiling. and it sticks. It expands to a few inches thick, and within 2 minutes it is hard.

V.O.Cs??? No.


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## Cabin Fever (May 10, 2002)

As homes become more insulated, and superinsulatedâ¦.and as homes become more tight due to better windows and being essentially wrapped in plasticâ¦the need for fresh air circulation becomes imperative. This is an issue youâve probably already considered, so Iâm not going to dwell on it. Indoor air pollution, due to greater indoor humidity, can and often results in the increased growth of molds and mildew. Likewise, modern building materials contain glues, plastics, and other man-made chemicals that off gas into new homes. Because of these and other indoor air pollution problems (eg, smoke, carbon monoxide, etc), many building codes require the installation of air exchangers in the home. I believe this is what CatsPaw was referring to. An air exchanger allows fresh air to be brought into the home and at the same time exhausts stale, humid and âpoluttedâ indoor air. The air exchanger has an internal heat exchanger which transfers the heat from the outgoing indoor air to the incoming outdoor air such that the use of the air exchanger doesnât rob the home of heat. If youâre serious about superinsulating a homeâ¦or even building a âtightâ homeâ¦you really have to install an air exchanger.


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## gccrook (Nov 21, 2003)

CatsPaw said:


> Next The last time I priced spray foam insulation about 6 months ago, for an 1800 sq.ft. house would be about $9000 compared to $1200 for standard, in a 2 x 4 framed house.
> 
> Air handlers, the last I heard, could run an extra $2000-$4000 (I think this was on a fairly large house....maybe 3000 sq.ft.) You will HAVE to have one if you make the house really tight. Between various unseen molds and v.o.c.s and cooking fumes and other things, indoor pollution is becoming a real topic.
> 
> Any way just some thoughts. Maybe some day I'll actually know the answer.


My 1600 sq ft addition with cathedral ceilings cost $4000 to have it sprayed with Icynene.

An air exchanger for 4000 sq ft can be had for less than $1000. I am not putting in an air exchanger, because most of the time we will heat with wood, and generally get hot enough that we open a window any way. The advantage of the insulation for us is in being able to close the house up for the day after cooling it down in the morning, and retaining that temperature for most of the day. 

I have to say, that I was also willing to pay for the sprayed in foam, as it kept me from having to work with fiberglass. Also, when I have to crawl in my very small attic area (scissor trusses) I will not have to worry about getting all itchy from the fiberglass. The other benefit of the foam is the sound dampening. It is so quiet in there when we shut the windows.


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## ET1 SS (Oct 22, 2005)

gccrook said:


> My 1600 sq ft addition with cathedral ceilings cost $4000 to have it sprayed with Icynene....


I understand, it cost double as you had a contractor do it for you.

How long did it take?




> ... I have to say, that I was also willing to pay for the sprayed in foam, as it kept me from having to work with fiberglass. ...


You paid for the foam because you did not want to work with the fiberglass ???

It sounds like you paid someone else, so your not working with either. I missed something


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## Randy Rooster (Dec 14, 2004)

ET1-

Where do you get or buy the stuff to do the foam yourself?


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## ET1 SS (Oct 22, 2005)

http://www.efi.org/wholesale/index.html

http://www.efi.org/wholesale/2005.pdf

Each 'kit' is two tanks [they look like propane bottles], and will cover approx 600 square foot of wall or roof with a inch of hard styrofoam.

The two components mix togehter to form an epoxy, so it sticks to everything. Heats up and expands, within 2 - 3 minutes it is hard.

I shot a bunch of it over the summer, and found that most kits did run right about 600 square foot of foam, when shot at 70-80 degrees temps. I noticed that as the temps have been dropping that the amount of foam that I got has been droppign off. I found [towards the end of our project] that it works better when the tanks are really warm. The temps here have been dropping, and the foam was not covering the full 600 square feet. Then on a hunch I dropped two tanks in our jaquzzi to soak at 100 degrees, for a while before using. And now the last two kits that I used both made far more than 600 square foot of very nice foam. Maybe closer to 1,000 square foot per kit.

It is pressurized with Nitrogen, and it does outgass. Immediately as it is heating and hardening it gives off some stuff. Though I did not wear a respirator, and the MSDS sheets do not require that you wear a respirator. Once the foam is hard, any further outgassing is Nitrogen. So it does appear to be very safe.

It seals all air gaps, holes, and cracks. Stops all drafts, and once it is hard it becomes structural.

Like a foam-core exterior door, has two thin sheets of tin with foam shot in the middle, but the end product can be set on saw-horses and stood on.


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## gccrook (Nov 21, 2003)

ET1 SS said:


> I understand, it cost double as you had a contractor do it for you.
> 
> How long did it take?
> 
> ...


Point well taken. Actually, if I did it myself, I would have done standard fiberglass batts, as that is what I know how to do. So, I saw that as my trade off. I am still thinking about getting one of the kits like you used to do some areas in the older part of the house, and touchup some areas elswhere. Thanks for the info on your experience.


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## ET1 SS (Oct 22, 2005)

I was reading about this stuff, and called the company. Well wait, I was reading about the expensive stuff 'Froth-pak' by Dow. So I called and they sent my a couple small sample kits to play with. I sprayed one side of our garage roof in Ct, and I loved it. Then I read more about the stuff that you have to paint over it to protect it from direc sunlight 'Elasto-meric latex paint'. And my apartmetn building's roof really needs to be re-roofed, so when I started doing the paperwork with the city to prepare to re-roof. WOW!!! Did you know that you have to pay a bond that all of th eold roof gets removed and hauled to an approved haz-mat dump, and you msut have a permit and contract with an approved haz-mat company BEFORE a single shingle can be touched? And from New England the closest place that can accept roofing shingles is New Jersey? Wow did I learn a lot.

Anyway I decided to paint the roof instead. They wanted $18,000 to re-shingle my roof! So I painted right over the old shingles, no permits were needed. LOL. And this paint is guaranteed to last 5 years minimum. Not bad for $120 of paint, as compared to $18k for a 10-year roof.

Anyway, you can contact DOW and you can get to play with the stuff for free, just to see if you like it.

Good luck.


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## Randy Rooster (Dec 14, 2004)

Once again thank you everyone for all the great information.


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## hickbynature (Aug 3, 2005)

Responding to CatsPaw, I agree there is the layout of cash and all of the financial cost/benefit analysis. Take either or all of the folowing what if's and re-calculate: SHTF, wars, cost of petrolium products going up (possibly WAY up). Any possibilities of energy crisis in the future. For those Christian types, end-time events, wacky environmental happenings. Global environmental changes, manmade or not. Age and lack of ability to split as much wood i.e. needing to heat with less. When what we have will have to stretch further, then comes the payoff. Of course each individual needs to asses where their money is best put. My gut says more is better. The sturdier, more efficient, easier to use and live in is long term benefit. Especially if unforseen things change. Naturally one would not want to be sunk by debt before these things happen either. 
Sick building syndrome is under-estimated. We need to address that. On the other hand, well sealed and with slightly positive pressure in a home, nasties like dirty bombs/nuclear fallout may be more easily survived. 

Not looking for these events to happen, but why not consider them and be prepared? Seems to me that homesteading involves being in a better place, prepared for what if's. I think someone once said to work out our own salvation . . . 
--HBN


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## ET1 SS (Oct 22, 2005)

HBN-

I agree.


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## genebo (Sep 12, 2004)

When spraying foam on a cathedral ceiling, you need to install the plastic air vents first. That keeps the foam away from the underside of the roof sheathing. If you don't then heat will build up in the roof and your shingles won't last.

When spraying foam on walls, you can get away with spraying as little as 1/2" to seal all cracks and leaks and add soundproofing. Then insulate with fiberglass as usual. The extra compression of the fiberglass is insignificant.

Spraying 1" of foam in a 3.5" cavity followed by fiberglass will yield an R factor of 19-20. Sometimes this works better than going to 2x6 studs, because of the extra problems that 2x6's cause, like extension frames for windows, doors and such.

Genebo
Paradise Farm


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## CatsPaw (Jun 16, 2006)

Back to ET1.....v.o.c.s....the propellant is N2 but the chemical reaction between the urethane resin and catalyst outgasses other constituants. I don't know what they would be, but, I'm sure there are people that would find them offensive. And they don't necessarily go away after a day or two. I built a straw bale for clients that wouldn't even let us use liquid nails under the subfloor.

If I could have afforded the foam for my house I would have done it fer sure. I think it adds a tremendous amount of strength to the house also (everything is "glued" together.)

And what Cabin fever said about "tight". I've been in houses where you had to pull the door closed due to the air pressure and when you opened it you could here the "whoosh".

"Prices may vary." Things can get real wild on contractor prices. Never know what it'll cost until you get a quote.

The glue-y cellulose interests me. Recylced paper and what hopefully is a more organic glue (I'm thinking this because I think you can recycle the glued stuff thru the hopper as you go along.) Could get a pretty good seal and still appear to be "green".

Hickbynature, yea, I think it's a tough decision. Looking at the future seems to be a real gamble these days. I like to think what I build will be here long after I'm gone. The stronger the better.

As a contractor, it's tough to sell some one on building better and greener when the first words out of there mouth are "Well, were on a really tight budget." Nothing wrong with that. But when I read all these green building articles and understand how expensive it can get, it can get to be a hard sell.

Wish people would be smaller...er...uh...cozier...and better...than McMansion and cheap.


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## ET1 SS (Oct 22, 2005)

http://irc.nrc-cnrc.gc.ca/index_e.html



> (3) When polyurethane sealants are foamed-in-place there are volatile organic compound (VOC) emissions as they cure. Precautions are addressed in the manufacturerâs documentation to be followed by the installer. In-service after curing, there are no VOC emissions considered to pose a threat to the occupants in new construction due to curing time which has lapsed , little quantity of sealant and finishing/moldings installed acting as barriers into the suite(s). Results from emission
> tests indicate that the product would be unlikely to cause a major adverse health problem to occupants after curing. While the testing and evaluation represent the current state-of-the-art in toxicological evaluation, such tests and their results do not purport to be conclusive with respect to the impact on health.


It is all dependant upon the 'cure-time' of the foam. And building codes require that it be stated on the MSDS sheets. During the curing process it does give off stuff [I just read through the stuff, and I can post it, if anyone truly cares], but as I read the sheets and websites, as soon as the foam is curing, the outgassing of organics is done.

Each foam has it's own different cure time, the product that I have been using cures in 2 to 3 minutes.

Laws were put in place decades ago to restrict and track all of this topic.

As I understand the area where V.O.C.s are still a going concern is fabric [ie, carpeting and drapes].


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## CatsPaw (Jun 16, 2006)

yea! right that's what They want you to beleive.....!

just kidding. It seemed to me that once cured there shouldn't be much of anything.


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## ET1 SS (Oct 22, 2005)

My understanding was that at one time, it was a huge problem. But then laws were passed, etc. And now we have MSDS sheets, and better environmental standards.


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## mondakkid (Oct 17, 2006)

Hi....Insulation is the best investment you can make when building your house....any part of the country. I now live in North Dakota and plan on building a house/shop near Kingman, Az. I plan on having a R 30 in my walls and R 50 in the attic. Put insulation on the outside of your foundation. About the only way to really increase the R value of the walls is to use foam sheets. There are many different types of foam panels. The R value also vary. The highest R value is urethane foam. The problem with urethane foam is that it is flammable. Better check your building code before you use it. I would not recomend using the spray on type unless it is covered with sheetrock. I plan on using a wall 10 1/2 " thick and will be using spray on celloulose insulation. I have a design of a wall only using 2x4 's to get over R 30 in the wall. There are many books out that can help you..check your local library. Good luck on your project...mondakkid


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## Explorer (Dec 2, 2003)

mondakkid said:


> Hi.... I now live in North Dakota and plan on building a house/shop near Kingman, Az. I plan on having a R 30 in my walls and R 50 in the attic. ...mondakkid


From your screen name I gather you now live in the Wiliston, ND - Sidney, MT area. Kingman will not have the temperature extremes you currently can experience. However, a well-insulated building is worth the effort, but one can go to extremes.


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## mondakkid (Oct 17, 2006)

Explorer said:


> From your screen name I gather you now live in the Wiliston, ND - Sidney, MT area. Kingman will not have the temperature extremes you currently can experience. However, a well-insulated building is worth the effort, but one can go to extremes.


 Hi Explorer. You are right. I do live in Williston and have a small farm near Fairview, Mt. I am going with solar on my building project. Most builders of solar homes now recommend the higher R values, even in northern Az. Do you know of any workshops, etc on solar, wind, etc. that will be held in Az this winter or next spring? Keep cool...jerry


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## ET1 SS (Oct 22, 2005)

mondakkid said:


> Hi....Insulation is the best investment you can make when building your house....any part of the country. I now live in North Dakota and plan on building a house/shop near Kingman, Az. I plan on having a R 30 in my walls and R 50 in the attic. Put insulation on the outside of your foundation. About the only way to really increase the R value of the walls is to use foam sheets. There are many different types of foam panels. The R value also vary. The highest R value is urethane foam. The problem with urethane foam is that it is flammable. Better check your building code before you use it. I would not recomend using the spray on type unless it is covered with sheetrock. I plan on using a wall 10 1/2 " thick and will be using spray on celloulose insulation. I have a design of a wall only using 2x4 's to get over R 30 in the wall. There are many books out that can help you..check your local library. Good luck on your project...mondakkid


To my understaidng that only insulation that is not flammable is rockwool.


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## Explorer (Dec 2, 2003)

Kingman is about 30 miles and a couple thousand feet higher than Bullhead City that generally is the HOTTEST place in AZ. Cooling will be more of a problem than heating. I haven't researched the temps in Kingman, but I would expect the average winter lows to be in the high teens maybe a little warmer.


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## Explorer (Dec 2, 2003)

Just by chance a friend that moved to Kingman called me this morning. I was wrong, Kingman is about 3000 feet above Bullhead City. The low temps range in the winter from the 20's to the high 90's in the summer.

Very similar to where I live. Little heating or cooling needed. A small wood stove with an external solar air heater does fine. A room air conditioner will handle the bedroom in the summer. I have central air and it uses about $40-50 of electric each summer, TOTAL. If I had it to do over, no central air with a couple of 220 volt room air conditioners.


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## vinylfloorguy (Jan 7, 2005)

But what does everone think of insulating in the floor joists? I have never seen it done in my part of the country, but did see it on one of those home improvment shows. I'm in north central nebraska and have a craw space of about 4 ft high. My floors do get pretty cold in the winter.


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## ET1 SS (Oct 22, 2005)

I stapled the PEX tubing and sheet metal up underneath the subflooring, between the joists.

Though I have spoken with a couple contractors who just thought that I would naturally be hanging insulation underneath that. Like to seal off each joist.

I have stuff in my crawl space, so I don't really want it to freeze; and I figure that any heat that does go down there eventually needs to go back 'up' right?


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