Liquid Rubber for water-proofing tanks and growbeds?

[Cai Robertson]

     I was going to use epoxy to waterproof my plywood tanks and growbeds, but I am concerned about BPA ending up in my fish and vegetables.  I found something called Liquid Rubber at Home Hardware. It's about half the cost of epoxy, doesn't off gas (Zero VOC), is water based and says it is safe for ponds.  There is no information to be found about it being foodsafe.  I even called the number on the can and I was told that it is being used fish tanks, but could not say it was food safe.  The only other product I can find is Pond Armor, which is a VOC free epoxy sealer, and is said to be safe for hydroponic use.  The Pond Armor costs about twice as much as normal epoxy.  I would really like to use the liquid rubber, but want to have some peace of mind.  Any input would be appreciated.

http://www.liquidrubber.ca/

http://www.pondarmor.com/index.htm

[Cai Robertson]

Did you check out the rubberizeit website?  I think the thicker stuff would work fine over your shingles.  There's a spot on the site showing a bunch of flat roofs that were done.  It is also safe for potable water so I don't think you have to worry.  I'm getting the guy to send me the data on it. 
 
TCLynx said:

I've heard there are elastometric coatings you can use over asphalt shingles and I'm looking for one that would be relatively safe to collect rain water off of.  I would prefer if I could get one that is white to help reflect some of the heat but at this point I'm more interested in the water but I need to make sure this stuff would work over such a surface without requiring too much extra maintenance.

[Tom McLemore]

The site says it can be used for rain water harvesting so I'll bet it's safe. White would be much better if they have it but I did not see a color choice anywhere.

[Cai Robertson]

There are a few different products on the Canadian site that come in diferent colors . . . . http://www.liquidrubber.ca/retail
 
Tom McLemore said:

The site says it can be used for rain water harvesting so I'll bet it's safe. White would be much better if they have it but I did not see a color choice anywhere.

[Paul Van Lare]

I have not seen this product used over a shingled roof, however it could be used in place of shingles on a roof. When it is applied by an approved applicator there is a 10 year warranty. Another great thing about Rubberizeit is that if there is damage from a branch or something, you can paint a little UG on and seal it as well as new. The concept of reflectivity has been addressed and the developers are currently working on a light colored surface coat. The IG is available in different colors, but current availability in the US is limited unless a very large quantity is desired, for a commercial roof, a bridge, or something like that.

[Tom McLemore]

Can it be painted over after it dries?

[Cai Robertson]

After ten years, would the old rubberizeit have to be removed before another application?  I'm having visions of doing my roof in this stuff now, with treated water catchment gutters all sloped to a central cistern.  If I could simply apply another coat in ten years, I would be saving money on shingles for sure, with the added benefit of a potable water safe surface. 
 
Paul Van Lare said:

I have not seen this product used over a shingled roof, however it could be used in place of shingles on a roof. When it is applied by an approved applicator there is a 10 year warranty. Another great thing about Rubberizeit is that if there is damage from a branch or something, you can paint a little UG on and seal it as well as new. The concept of reflectivity has been addressed and the developers are currently working on a light colored surface coat. The IG is available in different colors, but current availability in the US is limited unless a very large quantity is desired, for a commercial roof, a bridge, or something like that.

[Paul Van Lare]

Any latex paint will stick, but will fracture, when painted over RubberizeIt.  We hope to be offering a VOC free paint that has a comparable elasticity within the year.

Tom McLemore said:

Can it be painted over after it dries?

[Paul Van Lare]

Yes it can, however the paint will fracture when/if the rubber stretches.

Paul Van Lare said:

Any latex paint will stick, but will fracture, when painted over RubberizeIt.  We hope to be offering a VOC free paint that has a comparable elasticity within the year.

Tom McLemore said:

Can it be painted over after it dries?

[RW]

just curious, what did you decide to go with?

[Cai Robertson]

 I'm going to epoxy all the plywood joints and water proof the tank and beds with Liquid Rubber.  It is approved for potable water in the EU so I am comfortable enough with that.  I have also read that epoxy used by non-professionals is that much more prone to toxcicity if the correct ratios are not used.  The liquid rubber is also a lot cheaper at $50 a gallon at my local Home Hardware. $200 for 5 gallons if I special order.  It's easier to work with too, it's thicker and less toxic during application. 

[TCLynx]

Keep us posted on how the project goes Cai.

[Cai Robertson]

TCLynx said:

Keep us posted on how the project goes Cai.

I'm getting my design right in google sketch-up before I start.  I have limited space on my front porch as there is another door and there has to be adequate walking space.  I am wondering what might be recommended as far as plywood goes.  I think I might be able to get away with 3/4 inch but I am not sure for the longer sides.  1 inch costs about twice as much.  I might go with the 1 inch just to be safe but if you know of any projects involving plywood tanks and beds, I'd love to get a link or two to see how they worked out.  I will be starting a blog post for this project.