I purchased a bottle of SikaLatex 1-Gallon Concrete Bonding Adhesive and Acrylic Fortifier at Home Depot. I use to paint the solution on and wait for it to dry. At Home Depot they said you could mix the Adhesive directly into the concrete or mortar. What I would like to know is what the ratio of Bonding Agent to concrete or mortar is. Any help in this area would be greatly appreciated. Thank you in advance.

quote:

Originally posted by Clarke:
At Home Depot they said

That there is the problem. Very few HD employees know much more about home improvement beyond "paint is in aisle 17"

I've never heard of mixing the bonding agent in with the concrete and can't see how that would do any good. The purpose of the bonding agent is create a layer that bonds with the old surface and the new mix on top. The problem area is the old concrete, not the new.

I can't claim to know about every product out there, so if there is some form of bonding agent that is designed to be mixed in with new concrete, then that bonding agent will clearly have a mix ratio in it's instructions.

Clarke:

Actually, mixing cement and glue has been common place for decades. The prefix "Polymer Modified" simply means that POWDERED glue has been added. So, a Polymer Modified Thinset is a normal grey thin set to which powdered glue has been added. When you mix water into that polymer modified thinset, it activates the glue, and the resulting thin set acquires the properties added by the glue, according to the ratio of glue to cement in the colloid. That is, the thin set both sticks better and has a greater degree of elasticity and flexibility to it. And, the more glue you add, the better it sticks, stretches and flexes. That's why thin sets with a lot of powdered glue in them emphasize the amount of glue with "racing stripe" names, like Ultra-Flex 1000 or Elasto-Grip XP.

(I used to have the local Mapei sales rep on my speed dial, cuz the flooring installation supply store I used to deal with sold primarily Mapei products, and I use Mapei products for all my ceramic tiling and flooring cement needs, and I met the local Mapei sales rep and got to know him well. I still recommend that the best source of information on a particular product is the manufacturer's local sales rep or sales agency.)

There is no "correct" mixing ratio of glue to cement. The more glue you mix in, the more the resulting concrete will have the properties of glue in it... it'll stick better and retain more flexibility and elasticity. The less you mix into your cement, the less the resulting cement will show those properties. It's like deciding how much cream to put in your coffee... the more cream, the more the resulting coffee will have the properties of cream, like a light colour and a lot of calories.

However, like Jaybee says, you can always phone Sika's 1-800 tech support phone number, tell them what you're doing, and ask how much bonding agent to mix into your water, and then use the resulting solution to mix your concrete. (You'd still paint the bonding agent on the old concrete, tho.) If it wuz me, I would feel anything higher than mixing 1 part bonding agent with 2 parts water would be about as high as you'd ever wanna go, and 1 part bonding agent with 3 or 4 parts water would be more typical. Mix the bonding agent into your water, and then use the resulting solution to mix your cement and apply that to the old cement that's already been pre-painted with bonding agent.

And, cement is not the only thing you can mix glue into. I've been buying Synko Pro-Set 90 drywall joint compound in the bag for over 20 years now, as well as either GP's Perlite Admix Hardwall or CGC's Structolite base coat plaster and I regularily mix Weld-Bond white wood glue into any and all of them to make the compound I want. I mix a lot of glue into the mixing water first if I want a base coat plaster or joint compound that's going to stick well and dry hard. I mix less (or even no) glue into the mixing water first if I want a base coat plaster I can scrape down easily with a paint scraper or sand off easily with a sanding screen. The more glue in my mixing water, the better my compound will stick and the harder it'll dry.

And, even now that I've been doing that successfully for over 20 years in my own building, I still get newbies thinking I'm trying to give them stupid advice for suggesting that. They just don't realize that the difference between the "Regular", "Finishing" and "All Purpose" joint compounds they choose from when buying joint compound is the amount of glue in it.

Years ago, the Crest Grout Company used to make a liquid "additive" (pronounced "adhesive") that you'd mix your grout with. Nowadays all cement based grouts are "polymer modified" too, so the glue is in powdered form mixed with the dry grout. You can "polymer modify" any powder, even talcum powder, if you wanted to stick a baby to a wall, say.

This message has been edited. Last edited by: Nestor,

Short answer, every time I have seen it in use the product was applied to the old concrete with a used brush.