Concrete Prep

[Chris705]

My Sika joint install was an overfill and cut flush (no epoxy) .... I wonder if not cut flush caulk does the ‘skin’ remain tacky? I can’t say my caulk turned any darker due to dirt & dust being held by it. It did make the adjacent concrete darker cause I did not tape it and I overfilled the joints slightly (I just used a razor blade to cut flush). The color is a match to my light gray concrete.

 

[lakeroadster]

Is Sika Polyurethane Gray acceptable to use to fill in my saw cuts? Just looking to keep those voids clean / free of debris.

I used this on my barn Dan, worked really well.

https://www.homedepot.com/p/Sikaflex-10-1-oz-Self-Leveling-Concrete-Sealant-Gray-7116070/300934515

Keep in mind though if the tube of sealant is warm it'll come out pretty runny. (I sat the tube in the sunshine for about a half hour). And because of it being runny, I used like 4 tubes. I got 2 more and before using it filled the cracks with some sand, then swept them with a corn broom so the sealant was about 1/4 to 3/8" deep. Then when I applied the sealant it didn't wick way down through the crack.

It does tend to show tire marks, and it isn't a uniform color once it gets stuff tracked onto it. I installed it convex into the cracks.. so being "humped up a bit" is the reason it gets scuffed a bit.

My shop floor though is a "working floor".. I do some welding, grinding, woodworking, etc. so discoloration isn't a problem.

The 1st 3 photo's below were taken when I was installing the Sikaflex07-03-2017.

The rest I took this afternoon so you could see for yourself how it looks after 3 years.

Hope that helps.

 

[Dyno Dan]

I used this on my barn Dan, worked really well.

https://www.homedepot.com/p/Sikaflex-10-1-oz-Self-Leveling-Concrete-Sealant-Gray-7116070/300934515

Keep in mind though if the tube of sealant is warm it'll come out pretty runny. (I sat the tube in the sunshine for about a half hour). And because of it being runny, I used like 4 tubes. I got 2 more and before using it filled the cracks with some sand, then swept them with a corn broom so the sealant was about 1/4 to 3/8" deep. Then when I applied the sealant it didn't wick way down through the crack.

It does tend to show tire marks, and it isn't a uniform color once it gets stuff tracked onto it. I installed it convex into the cracks.. so being "humped up a bit" is the reason it gets scuffed a bit.

My shop floor though is a "working floor".. I do some welding, grinding, woodworking, etc. so discoloration isn't a problem.

The 1st 3 photo's below were taken when I was installing the Sikaflex07-03-2017.

The rest I took this afternoon so you could see for yourself how it looks after 3 years.

Hope that helps.

That’s the same stuff I used. I bought 3/8” backer rod (smallest I could find) and started pushing it down into the cuts. I quickly realized I needed to cut the backer rod in half because it was a real pain to effectively to work it down into such a narrow space. I used painters tape and then laid down the product, let it skin over, and used a putty knife to remove the excess.