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I guess the subject says it all. Anyone tried it, have more data, seen it done before?
I hear that 30% of all peanuts get re-used; there is a 50% or better re-use rate in mailing centers. Even with numbers like that, it would seem there are plenty left over for a goofy idea like mine.
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Replies
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What are you insulating? I used them in my garage to insulate the frost free hydrant ,drain ,air pipe , phone, and electric pit covered it with 2x6s works great. Sucked them out with the shop vac to do a repair, then dumped them back in.
*Jim, Interesting thought....I know I have trashed enough of them this year to probably do the exterior walls of a good sized house !
*I am building a garage and was considering it for the wall insulation. The walls are 2x6 w/ 1/2" OSB; housewrap on the exterior. I guess I'd use taut poly on the interior and fill the cavities with the peanuts; finish with sheetrock.I am curious, is it possible to determine the resultant R-value?
*If they are just blown into the wall cavity wouldn't there be a lot of places where the air spaces would sort of line up? I know looking at parcels that are cushioned with them there is a lot of pretty big air spaces. In a wall those would allow heat/cold transfer. Now if you could get the air gaps down to what is inside the peanuts....
*if you mixed them with, say, cellulose, and blew them in... this would fill the voids.. but i wouldn't use them by themselves for the very reasons that fred outlined...
*Re: Foam PeanutsAre there not flamability criteria for insulations that are used in (residential) walls? Foam peanuts burn and give off lots of black (toxic?) smoke. I know that cellulose and the commercially available foams have fire ratings. Is the drywall a sufficient fire barrier?
*Too much of a fire risk!!! only 0.625 inch thick drywall has any fire rating to speak of --
*I guess I hadn't considered that part of it. Thanks to all who replied.
*FWIW, because of the fire risk as a home inspector I call them out as a potential major problem and recommend they be removed unless it can be established that they meet fire codes.
*As far as being a fire hazard - EPS (from which the peanuts are made)can be and has been legally used in sheets for insulation as long as it's covered by a fire-rated barrier such as drywall as BSEE-CM suggests above.I would expect that if you were using peanuts in a wallspace that you would want to compress them as much as possible to maximise the extent to which they entrap air. By the way Jim don't listen to anyone who tries to tell you that compressing insulation (eg. fibreglass batt) reduces its R-value per inch. This is a VERY COMMON MISCONCEPTION even among tradespeople and contractors who should know better. I have been accumulating EPS foam packing blocks in a big plastic shipping mattress bag in my basement for some time. I'm building a house next year and plan on placing the blocks on a sheet of plywood on a large plastic sheet and mulching them with my (cleaned) lawnmower. Before the (in-floor radiant) basement floor is poured, I'll be placing the "mulched" foam and any other peanuts (not enough to actually make its own thick layer, but more of a "dusting") on top of the crushed stone, followed by 6 mil poly, then the foamboard insulation, reinforcing, tubes, & concrete. Probably not going to save me too much on heat, but at least the foam's being used to insulate something; and NO fire risk. I hesitate to use them too close to the foundation walls because the foam also makes great insect condominiums. Anybody see any disadvantages, other than the work involved?Thanks - Brian.
*markls..under slab work you do not want a compressible material like groundup foam products...over your crushed stone i'd put the 6 mil poly.. then a 1" to 2" leveling bed of sand....then your foam board & radiant floor... also ...under a slab , i'd be using a 2 lb/cf density EPS ....
*Interesting ideas for the foam below the slab. A small wood chipper may make the job a little easier. I am picturing a running lawnmower being lowered onto a pile of packing blocks. Get in on video and send it in to one of those TV shows. With the static electricity you'll come out looking like the abominable snowman.Isn't it possible to include EPS beads IN concrete as well? I guess that is a question for another thread.Regarding compressing insulation. I heard that dense pack cellulose is a good thing; however, dense pack fiberglass is not. I think it has something to do with the conductive properties of the base material--glass being a good conductor of temperature, cellulose not. Dense pack peanuts would seem like a good idea.Anyhow, I think I will be abandoning the idea of using peanuts. I read an ad in the classifieds about some buildings being torn down and the parts being sold as scrap. I am going to see if there is some fiberglass batts that can be reclaimed. I guess I was looking for alternatives since I feel fiberglass is so darn expensive for what it is. I bet it costs near nothing to produce . . . (pardon my tightwad nature)
*jim... i'd use the damn peanuts before i'd use the fiberglass..and damn sure before i'd use recycled fiberglass batts.....to each his own...b but hey, whadda i no ?
*Jim,use cellulouse, because it is made from recycled newspaper (plus borate treatment), and becuase it should out-perform fiberglass in just about every way.I applaud your efforts to 'make your own building materials', but I think that insulation is not a good place to try and do that!
*Thanks Mike - I like that - a bed of sand. Also would minimizes piercing of the poly by footsteps. I'm not 100% sure what my contractor is intending to use but I'll discuss this with him.Jim - That's why the plastic sheet- to minimize the mess by gathering the corners (not just the neighbours!)- but I'll make sure not to do the mulching on a windy day!The insulation misconception I referred to is... 6" of FG compressed to 3" will have less TOTAL insulation value than when uncompressed, but squeezing two 6" batts into a 6" space will give you better insulation across the 6" space than would a single 6" batt; which is to say that its R-value per inch when compressed is actually greater, not less. Note that this is a hypothetical example and a 2X compression is likely excessive in real-world applications. To my knowledge the increase in conductance by increasing the density is more than offset by the increased ability to trap dead air. Having said that, I acknowledge that at some given point of compression for any type of insulation the conductivity will not be offset by its ability to entrap air.
*I have decided to go with blown in cellulose. I will go to a big box and take advantage of the "free machine if you buy the insulation"The two stores I called sell "40 sqft of R-19 for $4.50". I am looking for confirmation that that amount is roughly 20 cubic feet if properly installed. If that is the case I feel I will be able to better estimate the amount required. I have 2x6 studs and 2x12 rafters. I plan on putting air channel between the rafters and the thickest clear poly I can find. I think I will be able to shoot the rafter cavities from the peak.By the way, all the air channel I find is 22" or split it for 11". 22" does a good job of filling the space on 24" centers, but it seems that 11" is inadequate for 16" centers???I may elect to apply 1/2 or 1" rigid foam to the interior of rafters prior to installing the sheetrock. Will I need furring strips to hold the sheetrock or will I be able to fasten through the foam? (4-12 and 6-12 pitch, if that matters regarding the shear load on the sheetrock fasteners)
*jim, the coverage rates are printed on the side of the cellulose bag...loose blow... or dense-pak
*don't insulate the rafters,insulate the floor.You want to seal the top of your living space, with one continuous unbroken leak-free layer of insulation.If you put your insulation several feet up in the cold attic you will only prevent your roof from getting warm, and will not be best keeping your heat inside your living space where you paid for it to be (because the warm air will freely move into the cooler attic space and then leak out thru the un-insulated gable ends, and thru the ridge vent).The only place were you need to put the air channel is down near the floor, where the insulation will be laying, so that the soffit vents are kept open.I think that the 11" stuff will be enough for your 16"o.c. bays because you are not trying to cool the roof so much, as you are just keeping a path open for air to migrate up from the soffits to the ridge.
*Two words: cathedral ceilingsThe bottoms of the rafters are the interior ceiling.Makes a lot more sense now, huh? ;-)(this is meant as a sincere form of ribbing- I hope you are laughing)
*Jim,The only accurate measure of how much cellulose you are buying is the number of pounds. My supplier sells them in 19 lb. bags. Your mileage will vary depending on how dense you can get it to pack. The best I can seem to do with the machine available for rental in my area is about 3 lbs/cu.ft. 3.5 to 4 lbs is better if you can achieve it, as it will create a more effective air movement retarder.Steve
*We seem to have moved away from styrofoam peanuts, but I'd like to add another caution. Some of those peanuts are biodegradable corn-starch-based foam. Don't use those! They dissolve when they get wet. And make a great food for roaches, etc. You can test them by popping one in your mouth. If it dissolves and tastes starchy, it is corn-starch based. Many packages I get with mixed peanuts in them have some corn-starch-based ones in the mix. -David
*Dave, my dog loves the corn-starch peanuts, so perhaps a better test would be to see if your dog'll eat 'em. If not, probably they're styrofoam. Andy
*Not if his dog is anything like ours. She eats rocks, dw screws, nuts-n-bolts....a little styrofoam wouldn't phase her a bit.
*You don't have a dog, you have a goat.
*Andy: I always toss a few to my dog as well, but was hesitate to post that. Afraid that some animal rights type would state that there are nasty preservatives or some such in the peanuts and report me to the SPCA. Whereas, I tend to allow a lot of latitude for a species that licks its own butt, eats absolute garbage, and loves to roll in month-old moose gut piles. -David
*i "loves to roll in month-old moose gut piles"Great mental image! I thought I had pootch problems rolling with dead woodchucks. Rotted moose guts takes the cake though!
*Wife came home and asked why the dog smelled bad. I said, "Don't even think about complaining. She's 99.7% better (after three shampooings) then when she came home with gelationous moose guts and maggots all over her." Took our first year in Alaska to train her out of that habit.