Organic Insulation

Does anyone out there know of a way to insulate a house without going to a big box store?

I am looking for something with:
1) R-Value
2) Pest deterent
3) Fire retardant

I have a sawmill and can saw my own wood but I get hung up with finding a good insulation solution.

Please share with me your ideas no matter how half baked they may be.

I am really stuck on this.

Thanks

Ok not my area of knowledge, but ive heard of walls being packed with sawdust, rice hulls, and cotton seed hulls by old timers, i dont know if there much good as far as R-value or fire retardant goes, but its something to consider, i also remember someone attempting an earthbag house using bags of rice hulls. seems there R-value was decent for that Application....also i believe ive seen some insulation treated with borates Sp?, the stuff in the mule team cleaner you buy at the store, its supposed to help with fire and critters, anyone got some more info on that

While poundering the house I want to build I came to the same problem, what to use in place of the pink stuff.....

I always wanted try something I have pictured in my head.  I pictured making a form out of 2x4's that mimicked the space in the rafters.  I would make cob with a slip consistency and completely coat loose hay.  Giving me cob coated hay that I would pack into the forms and allow to dry like sun bricks.  Then pop them out and stuff them in between the rafters.  Staple chicken wire across the rafters to guarantee they stay put and to have something to hold natural plaster.  I would completely plaster over the ceiling. 

I have no idea if this vision of mine would work or what the R-value would be, but the coating of cob would be pest deterrent and fire resistant.  I could do this myself using all natural materials, hopefully from my site.  All just as important to me as using natural materials.

I'll be interested to read what others have thought of for insulation.

Organic and fire retardant/resistant is a challenge.  Most things which were previously living tend to burn when dried.

Thermal Conductivity of some common Materials may have something.  The higher the number, the greater the conductivity.  Values less than 1 are insulators.  A k of .1 would be twice as effective an insulator as a material with a k of .2

Air
A dead air space is an effective insulator, k=.024
Hard to get more organic than fresh air, and the price is right.

Water
k=.58

Wood
Massive amounts of big lumber.  The k, coefficient of thermal conduction, of lumber is quite low, oak is .17
mind you, these values are for a 1 foot thickness of material, with no gaps.
Those old log cabins were cozy if the chimney was built well.
Balsa comes in at .048, but may not be available in 1 foot thickness.
Cork is .07, regranulated is .043
Wood may not meet your requirements due to insect and fire issues.

DE
Diatomaceous earth comes in at .06.
Best price can be had at big box stores.  Hmmm.

Dry Leather
k=.14
bug and fire

Sand-Dry
This shows promise at .15-.25

Sawdust at .08 is outstanding, but again, the fire and bug issues

How about a material covered with a fire and bug resistant material?
Strawbale may be that which you seek.

Don't forget: oak may have an R value of 5.8 (for one inch), but the metal nails you use will reduce that.  Cob made with straw has an R value of 0.5/inch; if in addition to the straw you add pumice at 30% to the mix, you have Structural Lightweight Insulated Cob which has an R value of 1.0/inch.

Dense-pack cellulose is treated with borates, has an r-value of 3.2-3.8 per inch, is insect resistant, and made from recycled newspaper. Concerns about settling are invalid when using the dense pack installation method as it is blown into wall cavities to a density of 3-3.5 lbs per cubic foot which is a higher density than what gravity can achieve.

Another option is rock-wool batts. Rock-wool has an r-value of about 4 per inch are made from recycled iron ore slag and basalt. It is insect and fire resistant. Environmentally it is a benign material as it requires no chemical treatment for its resistance to fire and vermin.

Next year I begin construction of my own home using a modified double stud wall and 3 layers of Roxul rock-wool insulation for a total of R42. Ceiling insulation will be the same material except to R60. Winter climate where I live is very cold and I am very excited about the energy savings I will achieve. I am hoping to get down to 2 cords of wood per winter from the more normal 5...

Rice hulls can be pyrolized. The process resembles charcoal making, but they contain enough silica that the result has a significant fraction of silicon carbide, which makes them non-flammable, indigestible, and extremely abrasive to the teeth/mandibles/etc. of pests.

I think horsetail is similar.

I've read that the pith inside sunflower stalks has a very high R value.

One company makes something resembling rigid foam insulation from seed husks and mycelia.

Oak galls are a traditional source of tannins, which are widely used by plants to improve the pest-resistance of organic materials.

Water glass is a fire retardant & preservative.

I have a hunch that interesting things could be accomplished with a dry mix of plant fiber (sawdust, post-consumer pulp) & clay, sprayed with whitewash in such a way that it remains fluffy. The idea would be to very loosely bond the fibers together with Roman cement. This notion of mine is inspired by papercrete.

Edit: fixed word confusion.

Like Jami, clay-slip (straw with a light coating of clay) is what came to mind on this topic. It could be made in modular blocks and then fitted between studs, or it could be placed into the walls with forms, working up from the floor and re/moving the forms as it dries.

I couldn't find any R-values for this method, but this book says that you'd need a thicker wall space to rival the R-values of the conventional insulation:

http://tinyurl.com/clayslipinsulation

Another book I have "The Natural House" says that you can vary the ratio of clay to straw for different effects; less clay is more insulative, more clay is better thermal mass.
Good luck!
PJ

Is the fire concern the reason you're not looking into straw bales?  If you get densely-packed bales, they are surprising fire resistant.  They smolder rather than burn.  Think like setting a phone book on fire.

Thanks for the book link PJ 

I do not want a strawbale house myself, I want a cob house.  But after reading about the slip-clay I'm liking that idea as infill more and more.... funny how you can envision an idea and there is already a book on it! Amazing.

I don't know anything about cob houses but it seems like many people talk about them here.
What kind of R-values can you achieve in cob construction?

Generally, cob has an R value of about 0.5.  It's not a good insulator, but it has great thermal storage.  If you mix pumice with the cob at about 30%, then you get SLIC -- Structural Light Insulated Cob.  SLIC has an R value of about 1.0 and is strong enough to meet California earthquake resistance standards.

"Cellulose" is organic by definition, right? And I believe it's widely available, big box store or not. That's what I've always heard is the best stuff.

several years ago i recall seeing an article on an insulating "pump in place" foam that was made from common organic material that could be d.i.y. formulated and pumped into cavities using a shop vac - and for the life of me i cannot remember enough of the details in order to do any sort of search -

i know there are many out there who's memory is better than mine - i hope you've also run across this idea -

For blowing into walls, as Joan suggests, there is an article on Mother Earth News about making your own paper insulation - it requires some special equipment so it may not be doable for everyone..... Same process is also outlined on eHow.com

http://www.motherearthnews.com/Do-It-Yourself/1977-11-01/How-To-Make-and-Install-Your-Own-Installation-for-Five-Cents-or-Less-a-Squa.aspx

Anyone mention Wool as insulation yet?  Got sheep?

I like this idea - http://www.ecologicalbuildingsystems.com/workspace/downloads/Natural-Insulation-and-Living-in-a-Healthy-Home.pdf

Seems this link above is all about a purchased wool product which includes polyester as an ingredient. Of course this 'better' wool product as they claim cost more.

In my reading I have gathered that using wool not suitable for garments, rougher carpet wool works well and cost less.  The wool has to be cleaned and then treated with borax - I assume that's to keep bugs out....?  And felted wool is easier to handle, but I wonder if stuffing the wool wouldn't achieve the same result. 

Anyone have experience using wool as insulation?

Instead of regular sawdust what about wood chips like from a planer? Spread them out in the sun, spray with a borax/water mix and dry before using.

Jami McBride wrote:
For blowing into walls, as Joan suggests, there is an article on Mother Earth News about making your own paper insulation - it requires some special equipment so it may not be doable for everyone..... Same process is also outlined on eHow.com

http://www.motherearthnews.com/Do-It-Yourself/1977-11-01/How-To-Make-and-Install-Your-Own-Installation-for-Five-Cents-or-Less-a-Squa.aspx

the cellulose insulation covered in the link you provided does sound promising - however, it is not the foam i had heard of earlier - that foam, while expanding only a limited amount, did firmly adhere to all surfaces contacted once the curing process finished - dang, i'm gonna have to find some memory enhancing mushrooms or something -

I don't know r- or u-values, but cattail down insulates very well.  might take you a good long while to collect enough, but I bet it would work a charm stuffed into wall cavities.

I was missing some chinking from between the logs of my cabin, decided to replace it with.. sheeps wool. That was about 6 weeks ago. I rolled, balled, started to felt it to make it compact, but springy so it would expand a bit, worked it into the empty spots. Looked great! Thought I was done.. but not so fast. It seemed the rodents in the neighborhood had not yet winterized their homes. My sheeps wool has all been removed and relocated by some industrious rodents.

Just thought I'd share my experience.....

Feral

Have you considered mixing your sheep's-wool felt with steel wool?  That might discourage the wee buggers.

Have to wait til shearing time next year to try a second go round.

I don't see it mentioned, but straw bales are a good option if you can get access to them, theres a nice video here: http://www.youtube.com/watch?v=kXNVem3o-Og unfortunately I think the full episode video (Grand Designs) that includes a decent size (for the uk anyway) building built and insulated with straw bales is unlikely to be accessible outside the uk.

The only thing I don't remember the video mentioning, though pretty obvious, is that the bales need to remain dry, but my understanding is that a tightly packed wall of bales offer similar r values to normal fibreglass insulation.

What an excellently presented video. I love the little cordwood house... wish it showed more of it!

Feral

Feral wrote:
What an excellently presented video. I love the little cordwood house... wish it showed more of it!

Feral

Absolutely, Kevin McCloud is an awesome presenter, Grand Designs wouldn't be the same program without him. I am drawn to watching it when ever I notice it is on TV, while I dream of building my own place :p

I was trying to find a link for cedar wood chips . ill have to get back to you .

I recently saw a video on TED where a guy figured out a way to replace styrofoam in packaging. His business is also developing the same concept to make a mushroom based insulation.

His TED talk
http://www.ted.com/talks/eben_bayer_are_mushrooms_the_new_plastic.html

Ecovative design - Check out Greensulate
http://www.ecovativedesign.com/greensulate/

It's is basically just using mushrooms "roots" to hold together cellulose, so you wouldn't have the problem of it settling, and you could use it in walls more easily. And as a bonus, it's a class 1 vapor retardant and class 1 fire retardant.

Lothar243 wrote:

It's is basically just using mushrooms "roots" to hold together cellulose, so you wouldn't have the problem of it settling, and you could use it in walls more easily. And as a bonus, it's a class 1 vapor retardant and class 1 fire retardant.

both links are very interesting - left some questions, though - did not hear anything relating to r-value - also noted one finished product was declared to be water-resistant at one point in the presentation and to be compostable at another point -  something wrong with that picture ?  wouldn't that be akin to being both fire-resistant and fire disposable ?

joan from zone 6 wrote:
both links are very interesting - left some questions, though - did not hear anything relating to r-value - also noted one finished product was declared to be water-resistant at one point in the presentation and to be compostable at another point -  something wrong with that picture ?   wouldn't that be akin to being both fire-resistant and fire disposable ?

"Resistant" is the operative word. For example, feathers are water-resistant and compostable.

Similarly, fireproof fibers aren't flammable, but fire-resistant ones like nomex can be incinerated (although this will go very badly if a typical amateur attempts it).

I wouldn't put too much faith in the resistance of this stuff to water. The package can get  a splash of rain without dissolving into mush, but don't regard it as waterproof the way polystyrene foam is.

They list the specs here:
http://www.ecovativedesign.com/greensulate/specs/

R value 3 per inch. They list other specs there too

you know fiberglass was originaly envisioned as a low cos replacement for wool

maybe cheep rug wool could make good attic insulation it is pretty fire and water  resistant

I read a short article in "Farm Show" about a year ago on a co-op of wool producers in Washington state that was selling wool batting for insulation. It was a way for them to sell wool that normally was land filled, because it did not meet spec for textile use. I had also seen a similar material from NZ.
kent

Here's what I'm considering.  I haven't been able to find anything that will work in existing walls but I think this is an awesome thing but not sure at the cost yet.

I'd luv to here more idea's......

http://www.youtube.com/watch?v=gLP64PoCQIc

Jami McBride wrote:Anyone mention Wool as insulation yet?  Got sheep?

Burns great.

pubwvj wrote:
Burns great.

Less filling.

(Sorry.  Couldn't resist!  )

You might want to check on the offgassing specs on the foam..many foams do. They didn't say anything about that in the video so it might be something you would do well to look at. Also, it sounded as though it is very fire resistant but what happens when it is attacked by fire? Does it give off toxins in that case? It may be that all is well,  just thinking it's good to know about these things before finding them out the hard way.

Apparently wood chips/clay is comparable to straw/clay but easier and faster to do
http://www.foxmaple.com/proclay.html  ..they say a foot of it ranges up to R25 depending on the density etc.

Jamie: Thanks for the link to the Mother Earth News article!  I have just found out that I will have access to a hammermill this summer and am delighted and grateful for the detailed info.

machinemaker wrote:
I read a short article in "Farm Show" about a year ago on a co-op of wool producers in Washington state that was selling wool batting for insulation. It was a way for them to sell wool that normally was land filled, because it did not meet spec for textile use. I had also seen a similar material from NZ.
kent

Something like this? http://www.youtube.com/watch?v=l3EpioxQJqQ

I have just finished installing this.

It is shredded bluejeans cloth from the looms. Loom waste.
It is easy to install and smells like cotton.

http://www.youtube.com/watch?v=lMRHUFXD86g&feature=related

This is just an interview of the owner at a show, but you can see the insulation a little.

[I would love to try the wool.
It looks really good because when wool gets wet, it stays warm and never compacts.
And, I saw on that video that they said it was vermin proof.
I would like to know what they have used to make it insect proof.]

Anyway, this bonded logic shredded blue jeans insulation is really nice.
I am about to get the rest of what I need on Monday.

jeanna

I tried using wool from my sheep for chinking in my cabin this year.... it was gone almost as fast I could put it in. The mice and rats loved it.... I would be hesitant to use wool again based on that experience, although there is a difference between chinking and insultation.

jeannacav wrote:

And, I saw on that video that they said it was vermin proof.
I would like to know what they have used to make it insect proof.]

My guess is that they mixed the material with boric acid (not borax).