Attach EPDM to concrete block?

[randythawkins]

I am building my waterfall and have concrete block on the outside edges of it. I will line my waterfall with EPDM and, for some vertical places would like to attach the liner to the inside of the wall so that the liner will not flop away from the wall. (In the attached picture it is the wall on the left side, with the taller vertical edge, that is of concern.) I do not expect there to be much force on the liner - I want it "tucked up in place" where I have no place to actually "tuck it" along that vertical edge. It will be above the water line yet I need it in case I have splash due to falling water. I have searched the inet and found various roofing materials which appear to be a solution but, before I chose one of those, I thought I would reach out here and see if anyone has suggestions. Is there any form of Gorilla Glue that would work? A special form of tube construction adhesive? Would the foam used to secure rocks (http://www.lowes.com/pd_290094-48650-WFFS_0__?productId=3066381) adhere to the liner good enough to achieve my goal?

Thanks,
Randy

 

[sissy]

I just put my liner under the retaining wall block on my filter tanks .No glue holding it .I think the hot summer made the liner lay flatter and then heat picked up from retaining wall block .Not the same but all I could do to show you .

 

[randythawkins]

I just put my liner under the retaining wall block on my filter tanks .No glue holding it .I think the hot summer made the liner lay flatter and then heat picked up from retaining wall block .Not the same but all I could do to show you .

That is what I intend to do on my horizontal parts but I have a large vertical part that I want to keep the liner close to the wall.

 

[sissy]

Would the heat of summer and the blocks weight make it meld itself to the surface .Not sure any glues would hold rubber to concrete .Maybe you can contact some of the adhesive company's and ask them .Tell them eactly what you want to do with there construction glue ,a lot of them have toll free numbers on there tubes .Addy used pl roofing goop maybe that would work .Do a test set up and see what happens

 

[randythawkins]

RubberAll - http://www.watertighttech.com/products/roofing/installation/manual/page_04.shtm
CIM 1000 - http://www.pondshop.com/catalog/const.htm
Genflex - http://www.genflex.com/wp-content/uploads/2013/04/EPDM-Water-Based-Bonding-Adhesive.pdf

I just don't want to buy a gallon (or more) when all I need is a cup's worth.

 

[Waterbug]

Polyurethane (Gorilla Glue, Great Stuff foam, etc.) will adhere to concrete very well especially if the concrete is damped first,

It can adhere to EPDM very well in spots. Making sure the liner is really clean helps. Roughing the liner with coarse sandpaper helps. The foam (Great Stuff, etc.) is the same as the glues (Gorilla Glue, etc.) But the foam has to be used just like the glues. You have to clamp the liner to the wall while it sets up.

But polyurethane is not a good solution. It's difficult to use and doesn't last that long in this type of application.

Other goops are just that, goops. Pick any one you like, it's hit and miss. It's in the same class duct tape. Yes it works, for while.

The way I do this is to mechanically attach the liner to the wall. Two ways. Easiest and cheapest is you concrete screw a pressure treated wood or a plastic wood strip to the wall and then nail the liner to the strip with short roofing nails (big heads). If I want really strong I use toggle bolts instead of screws. Block drills easy with the right bit and it's easy to get the strip level and just where you want it. The only downside is the strip sticks out. Some times that's not good. If I'm veneer this all will rock the strip helps lock the veneer to the wall so it's good.

If I need a more flush solution I use a strip of aluminum and screw or bolt the strip so the liner is between the block and strip. Kind of a pain to keep everything lined up. Extra set of hands help.

 

[randythawkins]

I did a test last weekend and wanted to share my findings. I took a scrap piece of EPDM, a piece of the retraining wall block I had left over, and my can of waterfall foam. I sprayed the foam on the block, laid the EPDM on top of it, and set a scrap block of 2x4 on top of that. The 2x4 wood piece did not weight much and its purpose was simply to keep the EPDM held snugly against the foam.

After letting it sit for a day I tested it. With some effort I was able to peel the EPDM off of the foam but, at the same time, I was able to do this without it peeling away on its own -

My conclusion - I do not know how well the foam will adhere the EPDM long term but, for what I am needing, I do believe it will work for me. In my situation I have a vertical length of about 18" where I need the liner to stay close to the wall. It will be adhered both below and above this vertical spot and there won't be any forces trying to pull the EPDM away - I just won't want it flopping back and forth. With some careful approach I believe I can apply the foam so that it looks better than my test above and if it does get a little messy I am I not too concerned as the colors are similar and, when viewed it will blend in with the 'big picture' of everything else around it.

 

[topofthehill1]

If they work the same Gorilla Glue is a lot less messy.

 

[sissy]

gorilla glue is garbage here .I used it and now that water helps it adhere ,well not for me it does not .Even the gorilla tape does not do what it says .Great test randy

 

[randythawkins]

gorilla glue is garbage here .I used it and now that water helps it adhere ,well not for me it does not .Even the gorilla tape does not do what it says .Great test randy

thanks. After I have done what I intend to do with this test I will post pictures here to show better what I was trying to achieve (and, hopefully, show it to be a success <fingers crossed>).

 

[randythawkins]

OK, so here are the results...

First I carefully figured out where I wanted the liner to be and trimmed any excess. I then sprayed a small line of foam behind the liner, about 2" back from its edge. I sandwiched the liner and block together, placed a board on the outside, and clamped it in place with a couple of clamps. I did not clamp hard - just enough to keep things in place.

(The white paper towels were there to help prevent me from running into the ends of the clamps as I was moving around and doing other things.) After many hours of sitting I removed the clamps and board.

Everything seemed OK and it was held as I wanted. I do not know how this will work long-term but as I pile/stack rocks against it I think it will work just fine.