Plastic Bottle Insulation


Introduction: Plastic Bottle Insulation

This is my first instructable

As everyone knows wasted heat is wasted money, energy, and comfort.

I was trying to find the greenest, most cost efficient way to insulate my house. While searching for insulation i discovered that gases are really the best insulators. (other than a vacuum thanks Gofish)

After scratching my head a couple of times trying to figure out how to seal off air in my 1960s home, I though duh empty bottles.

Step 1: What You Will Need

1. Empty bottles (with lids)
2. Empty attic space
3. Filler, this can be almost anything,
like expanding foam or blown in insulation
but for more recycling i used plastic bags.

Step 2: Scout It Out

As you can see my attic has no insulation whatsoever.

Step 3: Wrap the Bottles

start wrapping the bottles in the plastic bags as shown

Step 4: Start Stacking

Start standing them side by side.

Step 5: I Think I Need More Bottles....or Less Attic

This should help keep a few thousand empty bottles and plastic bags out of the landfill.



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    just to improve on this idea put bottles sideways , only fill every 10th one with water or a small amount in each one place each group in a large thick plastic garbage bag and seal off. Free Cheap insulation!!

    i had this idea myself a few years ago , however why put water in them fresh air is a better insulator if you included a small bit of water in each one you would have an automatic sprinkler in case of fire and better insulation and less weight in your ceiling.

    How are those bags doing now, several years later? Those plastic shopping bags, will start to crumble to bits. Those are "biodegradable", and light, heat/cool cycles, work to degrade the plastic. Usually takes several years [approximately], to start coming apart.

    IDK about the plastic bottles...those last longer, for sure.

    Some have filled soda bottles with sand, and stack them to make walls, tying the capped bottle-necks together then covering both sides with chicken wire, and plastering with earth plaster or cement plaster...forming a massive wall which is insulated some.

    Similarly, plastic packing 'popcorn' will degrade with heat/cool cycles.
    However, I've successfully used those nitro-pak drink boxes [like you get soy milk, etc. in]; empty them, rinse well, let dry, re-cap. Then assemble into bundles that fit between your wall studs or rafters. I taped bundles together using packing tape. Those form a closed air space, and, they are reflective inside, have a _long_ lifespan, and resist heat/cool cycles nicely. We used these, to insulate the roof of a small camping shack...stacked to fit between 2x6 rafters, cover the whole assembly with Reflectix or heavy duty aluminum foil, then salvaged some 1/4" thick boards to cover that all in. Seems to work pretty's been there for over 10 years, and they still seem to be doing a good enough job...and importantly, still intact.

    In South Africa we have a huge housing shortage with millions of people living in tin shacks! Do you think it would be possible to assemble used 500ml soda bottles in a vertical position to insulate the walls of a shack? These could be "plastered" over with a mud and clay mix to seal off air leakage and improve the fire risk. I’ve toyed with the idea of stringing the bottles together in an alternating up / down pattern to minimise gaps creating a "bottle mat" the same size as an exterior wall Does anyone have any ideas on how to attach the mat to the tin wall?
    Would lightly scoring the interior side of the bottles be enough for the "plaster" to stick? Any low cost suggestions would be appreciated

    3 replies

    That would work... but heck mud and clay make great insulators on thier own.... I have seen straw bails carved with chainsaws then covered in clay/mud used as insulation... quite effectivly i might add. It would probably be better to use stucco slathered on the outside and inside of a hay wall and not just mud.

    Go here, be inspired!

    Everyone in Africa should be considering this guy:

    yes, why water in them? the weight would become tremendous. I hear that all you need is trapped air for insulation. Shouldn't empty bottles be better for this? What is the reason that people aren't doing this? Is there some health concern with the plastic of the bottles outgassing something? thank you


    have you seen what they do with aluminum cans and/or glass bottles in earthships where they use them like bricks in an earthen mortar? this might not be suitable for insulating the attic but for the walls of a building it is a great idea. here is one picture but sometimes they are plastered over and you can't see them at all. plastic bottles might be OK in that case because they would be behind the masonry and not such a fire hazard. in fact if you can get your bottles behind a fire barrier of any sort that would be adequate for styrofoam I would think you were as safe. and if you embedded them in spray foam first you would be even more protected and that would be light enough for the attic and you wouldn't have to worry about how they start to degrade and leak after a few years of sun and heat. also by filling the wall/ceiling cavities with bottles before spraying you could save a lot of the costly spray foam and still have decent R value as long as the bottles weren't big enough to develop convection currents inside. I think that is one of of the advantages of crushing the cans a little, though maybe they are just doing it to make them key into the mud better, though in this case they would be keying into the foam so still a good step to take.

    I noticed your bottles seem to be filled with water. My question is can your ceiling hold up that much water (assuming you insulate your entire attic this way)? Remember a gallon weighs about 10lbs. Have you tried cardboard as a quick fix until you can get some real insulation? I've lived in an accient house with crappy insulation before. To save energy we used all our flattened moving boxes to line the attic until we could move into a better house. Having all those moving boxes on hand also helped us get the hell out of their in hurry when we found a better place to live.

    If you are worried about fire, just put some borax (a fire retardent used in shredded paper insulation) around. Oh it also works as a pest control system, animals don't like borax.

    Air is only an insulator if it can't be moved. If you have any air leaks that can flow through the insulation then it fails. This is why windows are sealed and gas filled. Any air that can get in from outside will cool off the home in the winter as it absorbs the heat. The less air leaks you have the more energy efficient your home will be. I'm researching insulation right now for our house. I'm currently like the flame retardant foam insulation as it seals off air leaks. R value is almost meaningless if it lets air in. should have some information. Also check your local codes they might specify certain specifications otherwise you might loose the right to occupy the home if work needs to be inspected and fails.


    Course there is the flip side to a sealed tight home. It traps moisture and indoor pollutants.

    I wish punctuation would kill sarcastic people.

    ha-just saw that you said EMPTY bottles. sorry, i had a homer moment! i still think that sand or dirt would raise the r value without raising the "fire risk" so many have expressed concern over.

    i like the idea but water weight and the water freezing are drawbacks. the thermal boundary in your attic would be the ceiling. once you insulate, the attic will be whatever the outdoor temp it will freeze when the temp drops. i can't imagine that a bottle wrapped in plastic would not freeze. maybe sand or dirt would work as fill.

    i kno what im gonna insulate my cold bedroom with

    With the bottles standing up you get the same R value through the whole space.  You would get a far higher R value in you laid the bottles down on there sides.  Each layer of bottles would act as a separate layer of insulation from the one above it.  Creating a higher R value. 

    As for the plastic Vs fiberglass issue.  Insulation is sold in many forms besides fiberglass all of them burn and a lot of them draw bugs. For example there is Styrofoam it goes up like a torch.  And the bug drawers are made of shredded newspaper or recycled bluejeans or any other kind of fabric.  The only problem with plastic i can forsee is plastic isn't stable.  It outgasses as the gas leaves the plastic it become more and more brittle.  So over time if you put your weight onto the bottles they will crush instead of flexing.  So i would make sure that they are in a place you are not going to be having to travel over.

    If you buy your water buy the case, you could re-pack the near undamaged case, tape it up and shoot in some expanding foam as you mentioned. You would end with a brick of insulation then.

    1 reply

    That really makes sense to me. Good Idea. Sounds like a building material too.