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Q: drainage with plastic-bottles? Answered

hi, i made some sort of cellar that goes about 5 ft into the ground. its not supposed to be water-proof, but sometimes we get heavy rains here near the coast of nothern spain, so, whatever water makes it in there, i want to drain off. so i dug a slightly sloping ditch from the lowest point of the ´floor´ to a spot that has a natural drop about 20 ft away. i am looking for the cheapest way to get some drainage-effect. i was thinking of laying out sort of a ´pipe´ made from plastic-bottles from the trash and protecting them from crushing with natural stone lining the sides as well as the top. can that work? gracias, pit from los picos de europa


Jack A Lopez

22 days ago

There is a lot of variety in the plastic bottles I see in the recycling bins. Even when just considering one category of plastic bottles, e.g. transparent PET (poly ethylene-terephthalate) plastic, there are a variety of different shapes and sizes.

Anyway, I have been doing some experimenting of my own with PET plastic bottles. Mostly I have been focused on PET plastic bottles that come with rib-like structures built into their sides. Also, mostly what I have been trying to do is make plastic storage boxes, by cutting the bottom off of one bottle, and using it as a lid for another. Also an essential feature to this design, is the bottom part of the bottle-box fits inside the top part, and the ribs help to keep the top part locked in place.

I should probably attach some pictures of this, so people can see what I am describing.

Anyway, I guess where I am going with this, is it does not seem all that outlandish to me to make a long pipe out of discarded plastic bottles, especially if you are using the big sturdy kind of PET plastic bottle, like 1 gallon (or 3 or 4 liters in size) with lots of plastic ribs to make it strong.

Also there are other subtle tricks for PET plastic bottles.

In particular I am thinking of the fact that these bottles can be made to shrink in diameter, and become thicker and stronger, under the influence of hot air, like from a heat gun or maybe a hair dryer.

Maybe there might be a way to link two bottle sections together, under the influence of this hot air shrinking. Maybe with something rigid, in the middle, for them to both shrink onto.

I dunno. It it does seem like a lot of work, compared to going to the hardware store and buying some drain pipe.

Also I thought I would include a link to the Wiki article for, "French drain", since I think that is what the pros call the thing you're considering building.


la xerraJack A Lopez

Reply 22 days ago

jack, funny, i am doing the same (making *jars* out of plastic bottles - must be convergent evolution). and yes, heat is the key. the problem with heat-gun etc is: p.e.t. is very fickle, its ´even´ and consistent shrinkage is tricky. one way around this is: use a mold. that is to say: put the part you want to reduce slightly, just enough to slip neatly over the other plastic-body, over some simple mold - than gently apply the heat. this way the plastic cant go ´nuts´ and off on its own. ... i make ´containers´ out of about anything, small bottles, round, square... big water-bottles (here in europe the biggest so far was i think 8 liters).... much fun..... how can one not love trash!

btw, other plastics work too... though they dont shrink, you can just plastic-weld (soldering-iron, etc)

btw2, in the concrete case of a drainage-line: yes, absolutely... your idea to rig some kind of pipe works like a charm.... gravity (pitched pipe) takes care of any seals/couplings (ps, i made pipes for the cabin- gutters from stringed-up plastic-bottles)


Jack A Lopezla xerra

Reply 21 days ago

What you say about heating PET plastic to make it shrink, is consistent with what I have observed; i.e. "fickle" and likely to "go 'nuts' and off on its own."

It looks like there are handful of existing 'ibles on this topic. I know it is something people know about,

(via Let's make search for: shrink pet bottle with heat)


but I wonder if anyone has really mastered the art.

la xerraJack A Lopez

Reply 20 days ago

again, play around with molds/guides... slightly undersized of what your shrinking should end up being. thus: lets say i want to shrink a (cut) bottle i look around for some object that barely fits into it, and apply heat... at worst i rig something out of tin, wood, etc..... you guys in the *1st world* got all the means that are ´lacking´up here in the mountains. use ´em! play!... gracias

Jack A LopezJack A Lopez

Reply 21 days ago

I just wanted to add some pictures that show what I was describing, regarding turning plastic bottles into boxes, and how some kinds of plastic bottle are well-suited for this, by virtue of having these rib-like structures.

A few of these pictures show how the bottom part of the box gets compressed a little bit, so the top part of the box (which used to be the bottom part of a bottle) can fit over it. The fit is not air-tight. In fact, often times the fit looks kind of sloppy, with some sides of the bottom part, not flush with the sides of the top part. Some styles of plastic bottle seem to fit together this way better than other styles.

Because the fit is so sloppy, with gaps big enough to let air or insects through, these boxes are not really suitable for storing food. But they are good for storing non-perishable things.

Final note: the only thing that is misleading about these pictures, is they do not show the waste pieces. It takes two plastic bottles to make one box, and there is a lot of waste plastic left over. Usually I just throw those waste pieces back into the recycling bin that I stole the whole bottles from.

la xerraJack A Lopez

Reply 20 days ago

jack, why dont you publish some instructable on that topic.. i was thinking to do so but am currently a bit busy killing myself bolting new climbing-routes above my cabin.

few short comments:

_airtight: i actually manage to create some small (made from the necks of bottles) containers, both end with a screw-on cap

_waste: considering that you use stuff that would trypically go right in the *waste* .. to have some left-overs, aint bad... besides: i usually keep all the cuttings in a container to use them at some for something. also: one can make one container from one bottles, its just that the top wont be even, since it will be the bottle-top (neck and cap)... how its done, well, just cut the body at some point and shrink the part thats NOT going to be the cap

_heat application: my experience is that heatgun/hairdryer etc are an overkill.... i use the solder-iron,almost like a brush, to move gently over the plastic i want to shrink/form

_water: at some point in fall/winter when i stoke the burner here i will play around with using hot/warm water.... anyone any experience?

thanks all


25 days ago

I'm not sure how much PVC pipe costs in Spain, but in the USA it's fairly inexpensive, and really you wouldn't need the gravel if you get the correct pipe.
Another option, which I think would cost about the same, would be to get 50mm+ drain rock and wrap it in plastic sheeting creating a porous tube that would be resistant to infiltration by surrounding soil.
PVC comes in different wall thicknesses, so you'll want to get one that is rated for burial if you go that route, the thin pipe might buckle under soil.

la xerrasixsmith

Reply 23 days ago

hi, thanks for the feedback.yes, that would work fine. the problem is i am cheap (poor) and live in a cabin high up in the mountains (plus no car), so i try to find solutions with whatever the land provides (resp the landfill - there is plenty of the trash in the villages nearby). thus: rocks and plastic-bottle come for free.
latest idea: might give it a shot to make my own ´pipe´ - by first laying out a line of plastic-bottles (top and bottom cut) and then ´wrapping´ several layers of bottle-bodies (again, top n bottoms cut, as well a cut length-wise throughout) around the base-line-up... i figure 5+ layers of p.e.t. might be pretty sturdy.
anyhow, as always, and feedback appreciated.
the old man in the mountains