Sikaflex in saw cut control joints

[steiner5]

I want to start out by saying I have been a lurker on this site for some time and have learned a great deal from others experiences. An absolute treasure trove of information.

I am in the process of building a 4000 sq. ft. metal building. The building has been erected and just a few days ago I completed painting the slab with 2 coats of epoxy. The slab was poured 3 months ago. It is 6 inches thick with #4 rebar at 18" O.C. both ways and 4000 psi concrete was used. This building will be primarily used as a machine shop. I am to the point of wanting to fill the saw cut expansion joints and my plan was to use backer rod followed by sikaflex. I have read on this site of several individuals experience and plan to tape off both sides of the joint prior to installing the sikaflex. My question really pertains to the chips that have occurred along the saw cut joints. Some of them extend 3/8" beyond the edge of the saw cut. I know the sikaflex will not match the epoxy paint (light gray in color) so I would like the joints to be smooth and even. For those that have done this how did you mask off the control joints when dealing with the chips?

Thanks.....

 

[papp101]

I just did this. The self leveling will somewhat fill in the chips under the tape. If it didn't, I had one tube cut for a tiny opening 1/8", and just added a little to that area. The other way I addressed was literally taping out around them. Wasn't bad. However, that was on 656 sq ft. Not 4000.

I didn't use backer rod, but rather silica sand. Broomed it in, then took a screwdriver and brushed it out 3/8" deep.

Pics below of mine over hellfire coating.

Sent from my Pixel 2 using Tapatalk

 

[Toomanytools?]

I did same as Papp, taped both sides used a 1/4" backer where needed filled with Silka, it leveled into the chips. Any large chips I filled a bit more after I pulled the tape, after it's all done and things are moved in you hardly notice. The best thing is easy to sweep over the saw cuts.

 

[LegacyIndustrial]

Looks good Papp.

 

[steiner5]

Thanks everyone for your replies. It sounds like I should just tape over the chips but not press down on the tape in the chipped areas. This way the sikaflex can fill the saw cuts and will expand out into the chipped areas but under the tape. Is this correct??

Thanks again....

 

[tff]

In my case, which was only 600 sq ft, I just carefully squeezed out the Sikaflex into the cut till it filled it. I didn't use any tape. It did take a lot of patience but I wouldn't say it was difficult. (This way at least you can directly see where the Sikaflex is filling or not filling as it flows into the chipped areas.) Also in my case I just sealed the garage floor (no paint or coating).

 

[JOE.G]

Do you guys have a link to the product you are using? I have been meaning to do this to mine for years.

 

[steiner5]

Joe G, this is the stuff I am using. It is available in 10oz and 29oz tubes and gray or sandstone color. There might be other colors but those two are all I have seen.

https://www.homedepot.com/p/Sikaflex-29-oz-Self-Leveling-Sealant-Gray-7116080/300934522

 

[tff]

I used the same product.