20, 30, 40, 45mil liners

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A tiny snippet that might be useful to someone at some point... For me it was yesterday when trying to compare different liners from multiple different places. Buried deep in a dark corner of the internet is the gem explaining what exactly 45mil means. its 45/1000ths of an inch, or 3/64ths or 1.2mm in new money.

Theres a note on the Firestone website that says they now make 40 mil as their standard liner, but you can still get 45 mil. if you are wanting a 45mil watch out for 40. :)
 
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I only used .060 in my roofing projects and there always was. I was reluctant to use .45 for my pond.
 
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I only used .060 in my roofing projects and there always was. I was reluctant to use .45 for my pond.
Oh, nice find GBBUD! are you saying you used 60 as your pond liner? Very interested as it appears to be cheaper to buy 60 mil from the local roofing store than 45 from the fish shop... will be checking the tech spec for anything nasty...
 
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Oh, nice find GBBUD! are you saying you used 60 as your pond liner? Very interested as it appears to be cheaper to buy 60 mil from the local roofing store than 45 from the fish shop... will be checking the tech spec for anything nasty...
Build with .45 and then come back to me and say you want to add 50 percent more weight . NOT GOING TO HAPPEN
 
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Just spoken with Firestone Technical Services, very helpful. They don't recommend using 60 mil roofing membrane as a pond liner. It's not been tested with fish as the pond type has and although the ground where I'm putting the liner technically qualifies as an industrial tip, 45 mil will do the job but a semi rigid or rigid underlay would be more appropriate. hmm, thats a blow... back to plan A!
 
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They make liner they don't build ponds. Post some pictures of your soil. If you buy 12 oz or heavier non woven needle punch fabric trust me you will be cursing it everything you need to cut it as a brand new razor won't even give you two cuts with it Sheers are the only recommended way to cut the stuff it's more then likely plenty strong for your soils. And if you have realy realy realy bad you can always over dig your bottom and shelves and place 8 inches of sand. And that will keep anything from getting to the underlayment and liner.
 
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theres already some pics of the really, really, really bad soil here. the straight edges in the middle pic is a drain cover! current thinking is to pull out anything nasty, use 50mm polystyrene insulation, backfilled with sand, then carpet, geotextile underlay, then the liner.. still not decided for sure until I get the rubbish out and see what i'm left with.
 
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Oh, nice find GBBUD! are you saying you used 60 as your pond liner? Very interested as it appears to be cheaper to buy 60 mil from the local roofing store than 45 from the fish shop... will be checking the tech spec for anything nasty...

Take this with a grain of salt as I've never confirmed it, but I believe the only difference between roofing epdm and pond epdm is that they rinse/clean the pond epdm to remove any lingering surface chemicals from the manufacturing process.

Roofing rubber is cheaper where I am, too, but I couldn't find anyone who sells it in any size other than 10' wide rolls, which would have required me to do a lot of seams.
 
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considering .225 is 50 percent my apologies its 25% fight the roll dragging it up onto a roof and you'd say the same
 

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