Replies

1. 
   Henley | Mar 10, 2008 02:28am | #1

   your better off
   using dense packed cellulose.

   Has all those characteristics, easy to install and
   affordable.

   try posting over at Breaktime.

1. 
   goodwood33 | Mar 15, 2008 11:39am | #9

   I'm planning to make panels but can not find a binder. Borax has been sugested for pests(?).

   Japanese academic reserch sugests a chip density of about 100kg/M3 is more efficent  than fibre-glass.

   thanks for your responces

   Sacha   

1. 
   saschafer | Mar 16, 2008 01:40am | #11

   Hmmm. That's 100g / l, about 15% of the density of solid wood. It's going to take more than just a good binder to make something that light and airy (that won't fall apart at the slightest touch). I'll bet that the researchers were able to exceed the performance of fiberglass batts by forming a cellular structure (resin based?), a sort of "sawdust foam." That's the primary reason that fiberglass doesn't perform so well--it provides a relatively poor barrier to air movement.

   -Steve

    

2. 
   [email protected] | Mar 10, 2008 02:57am | #2

   Boric acid was used for that. 

1. 
   Henley | Mar 10, 2008 03:21am | #3

   That's what is in Cellulose insulation.

1. 
   [email protected] | Mar 10, 2008 04:18am | #4

   Well yeah, boric acid is what works. 

   I keep a plastic paint bucket with borax and water in the shop to rinse rags in after I use them to wipe down BLO, and danish oil finishes. 

   It also is a decent insecticied.  And, have been told it makes things taste bad to deer. 

3. 
   KiddervilleAcres | Mar 10, 2008 05:14am | #5

   Many years ago icehouses used just sawdust to keep the ice from melting.  It's very effective and I've found it in walls of old houses, presumably for insulation.  I wonder how effective cedar would be as a pest inhibitor?

   Regards,

   Bob @ Kidderville Acres

   A Woodworkers mind should be the sharpest tool in the shop!

1. 
   [email protected] | Mar 10, 2008 05:58am | #6

   They used to use it for insulation in houses, in just about every town that had a saw mill.  It isn't really a very good insulator, but does knock down the draftiness.  I guess given the option of nothing or sawdust, saw dust wins hands down. 

   Cedar would keep the insects out and be loved by the rodents.  They sell cedar shavings for pet bedding, because it keeps the fleas away. 

2. 
   zolton | Mar 16, 2008 11:21pm | #15

   Bob,

   My maternal grandfather ran a boarding house for years up your way - in Centre Harbor, on the western side of Lake Winnipesaukee.

   I can remember going into his ice house on a hot August day and using an ice pick to chip the corner off a huge block of lake ice that he had cut back in January and hauled up there to store in mounds of sawdust. Big pools of cold ice-melt water lying around on the floor and wet sawdust everywhere. The walls were about two feet thick, packed with sawdust.

   Kinda romantic to think back on all that. I'm sure there were bacteria teeming and mold issues, but as a kid I never thought for a moment about any of that...

   ZoltonIf you see a possum running around in here, kill it. It's not a pet. - Jackie Moon

1. 
   frenchy | Mar 17, 2008 12:12am | #16

   Zolton.

      Back in the day when sawdust was used as insulation material  buildings were a lot more drafty and thus the interior heat escaped drying out the sawdust and preventing mold..

    Today we seal the interiors with vapour barriers and the exteriors with housewrap  resulting in little if any air movement and mold is far more common.. issues of rodents were dealt with by barn cats eager for a meal.  House wives instead of calling expensive exterminators brought the cat around and showed it the entrance..

   Edited 3/16/2008 5:14 pm ET by frenchy

4. 
   saschafer | Mar 10, 2008 06:01am | #7

   If you're planning to use it for building insulation, I think you'll be disappointed in its performance. The wood itself is only so-so as an insulator (about R-1), and the shapes of most wood shavings isn't conducive to trapping air (which is what makes most insulation work).

   -Steve

    

5. 
   ChipTam | Mar 10, 2008 03:38pm | #8

   When we started remodeling our summer home in Atlantic Canada, we discovered tons of saw dust in the walls.  It's an 1880-era salt box right on the ocean and I was amazed that the saw dust remained totally dry after all those years.......not a speck of mold.  However, when the wind would come up, the remaining saw dust would fly all over the place and blind us.  There were a couple of days where we just had to quit early, go home, and wash the saw dust out of our eyes.

   Chip     

6. 
   AZMO | Mar 15, 2008 04:26pm | #10

   Borax is a great thing, but be careful. It is the best soil sterilant in the world. It is called borax because it is full of Boron. Boron is an essential micro nutrient for all plants. In soil levels at 5 PPM it is great. At levels of in the Parts ber Billion plants will not grow. If you dump your Borax water on the soil it will raise the PPM to a point of toxicity. The plants won't die overnight, but will steadily decline and turn yellow over a couple of years and then die. If you replant it will do the same thing. The Boron is absorbed into the plant slowly. If you want to get rid of a neighbors tree........ and don't want another one.

   AZMO http://www.earthartlandscape.com

    

                     

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7. 
   Henley | Mar 16, 2008 01:54am | #12

   Just thought I'd stop by and reiterate-

   Your going to be better off with Dense Packed Cellulose.

1. 
   frenchy | Mar 16, 2008 06:09pm | #13

   Henley,

    Amen!

    or even better foam.. wood chips will allow too much air movement to serve as a good insulator.  Plus wood is thermal bridge it's r value is low about 1 per inch.   That's why solid log homes take so much energy to heat during the winter..  a typical log wall has a R value of about 6 to 8

1. 
   PheasantHunter | Mar 17, 2008 01:03am | #17

   Frenchy:

   As a past owner of a log home, I would disagree about heating costs.  You can't base insulation value of a log home on R, it is the mass of the logs that is important.  My natural gas bill was less than $250 for that log house.  PER YEAR in MONTANA.  Natural gas prices have changed since I sold the house, however, that was less than 8 years ago.

   I am no expert on insulation, but I would buy another log house in a heart beat.  One reason being the low heating cost.

    

1. 
   frenchy | Mar 17, 2008 01:15am | #18

   Pheasanthunter,

    Thermal mass works both way..  it also bring the cold in  so unless it's inside insulation it's a wash.   

      Your bills mean nothing.  tell me about area,  costs, efficencies, and heating degree days etc..

     I will give you one little example.. My old house was well insulated.  I had a new high efficency furnace  double paned windows and about 2600 sq.ft.

     My monthly heating bills for Dec. and Jan. were $500 each month.

     Six years later I had the same furnace in my new timberframed house of 5500 sq.ft. with three times as many windows on exactly the same spot and my heating bills (in spite of cost increases) are now about $200 in Dec and Jan.

    In reality I cut my heating costs in a third.. while more than doubling my size and tripling the windows.  

    

1. 
   PheasantHunter | Mar 19, 2008 04:10am | #21

   Frenchy:

   Not looking for an arguement.   I don't have answers to all of your questions.  However, by comparison friends and family living nearby in stickbuilt houses of similar size, had yearly heating bills of 500-1500 dollars compared to $250 in my log home.  I realize this may still be comparing apples to oranges to you.  Plenty of info on the web about energy effeciency of log homes.   I doubt this will convince you, but I stand by my earlier statement, I would buy another log home because of the energy efficiency (now the exterior maintenance is another subject, probably best left to another forum).

   http://www.glulamlog.com/GLLNotes/Efficiency.html

   I would still not recommending sawdust for insulation.

2. 
   frenchy | Mar 19, 2008 06:10am | #22

   PheasantHunter,

     I agree this isn't something we are likely to agree upon..   I was open to the idea of a log home because I love wood and the more the better.. like you say it's a lot cheaper and easier to get a log home than a timberframe..

    However I did a lot of research into the subject before I gave up on the idea of a log home and took a timberframe instead..

     One thing I won't ever do is go poking around the internet looking at sites that make sincere sounding claims..For example:  I think ICF's are the greatest way to build a home but if you read some of the claims made on their behalf it's insane..

      I know this makes me some kind of luddite but I prefer Books.  I like to look at their sources and verify questions I have.. I also get to do a little looking up of the credentials of the author and verify his bckground..

    If I were computer skilled I could make a web site making all sorts of claims about the earth being flat and the center of the universe.. I could fake other sites confirming my statements..   I had a buddy get a job that way.. really high paying job in fact.  Worked there for several years before they found out the truth and discharged him .. turns out he hadn't broken any laws doing it..

2. 
   pzaxtl | Mar 18, 2008 07:03am | #20

   Now you've done it!  You disagreed with Frenchy (I like to call him "BS") and one must never do that.  He will forever argue with you, citing all manner of made up facts and historical data that never happened.  The truth is, Frenchy (BS) can never be wrong, even though he usually is.  Just you wait and see...

8. 
   troys | Mar 16, 2008 11:15pm | #14

   Before you go to far with this always be careful about using creative solutions for this kind of thing. I could see you doing this and 10 years down the road you go to sell your house and you or the buyer do a pest report and the person doing the report calls all of your insulation "cellulose" debris and says it all needs to be removed to clear the pest report. Anyway good luck

   Troy

9. 
   JohnWW | Mar 17, 2008 11:48pm | #19

   I would strongly recommend against do-it-yourself insulation.

   If it doesn't work for some reason the fix will be probably be half the cost of the original construction, if the building doesn't just burn down or rot beyond salvage. Also, if you are in an area where building codes are enforced your local building inspector won't approve it. A final problem is that your insurance company might not be interested in helping to pay for repairs on problems that they would consider self inflicted, and they might decline to insure you at all if they know what is in the walls.

   John White