Performing crack repairs for a garage floor is never fun. It slows things up and can even delay applying a coating to the concrete if you are trying to get the job completed in a weekend. Most crack repair products require 4-24 hours for the material to cure. Thanks to Legacy Industrial, cracks and small patch repair have just become extremely fast and very easy. Xtreme Set 100 crack and joint filler may be the best crack repair filler we have ever used.
Xtreme Set 100 consists of a very fast setting 100% solids polyurea. It’s formulated to be very runny when first mixed – almost like thinned honey. When added to a sand-filled crack or small patch repair, it soaks right in and cures up harder than concrete. In 20 minutes it has cured enough to be ground flush and have a coating applied.
One of the advantages of polyurea is that it is flexible (relatively speaking). Unlike most standard epoxy repair products, it can be used to fill contraction joints since it will allow some movement of the joint.
how fast and easy is xtreme Set 100?
Fortunately for us, Legacy Industrial was kind enough to send us some Xtreme Set 100 to test for ourselves. We received two 1/2 gallon containers of the part-A and part-B Xtreme Set polyurea as well as some clear plastic squeeze bottles for the application.
One other material requirement is clean play sand or silica sand which is used as an inexpensive filler. You can find play sand at your local home improvement center for less than $10 for a 50lb bag. Legacy Industrial does not include it in their kit due to the added expense of shipping heavy sand. One gallon unit of Xtreme Set mixed with sand filler will fill a 300ft. lineal void ½” by ½”.
Cracks and small pits in the concrete are prepped as usual. We prefer using a crack-chasing wheel for cracks since it makes for fast work. However, you can use a cold chisel and hammer to prep cracks and small pits as well.
Once the crack has been prepped, you will need to fill it with clean play sand or silica sand. We used one of the clear plastic squeeze bottles as an applicator for the sand and it worked great. Just clip the tip to create a larger opening.
Make sure the sand you use is dry. The play sand we purchased was damp and had to be dried out before use. The 100% solids polyurea will not react well if it comes in contact with moisture.
Since we didn’t have any good concrete cracks available for repair at the time of testing, we decided to create some of our own.
We purchased two quality concrete paving stones and used them for our test bed. One concrete paver was prepped for a typical crack repair. We also created a small divot to replicate pitting. For the second concrete paver, we ground a 3/4” deep by 1” wide groove in it to replicate a typical hand-troweled contraction joint.
Once we did this, we filled each repair area with the play sand and ran a putty knife over it to smooth things out. Don’t worry about being perfect. We then poured into a plastic squeeze bottle 1 equal unit of the part-A Xtreme Set resin and part-B hardener. Keeping the end capped off, we shook it vigorously for 10 to 15 seconds and immediately began applying it to the sand-filled repair areas.
The key to using Xtreme Set is to be fairly quick with your work once you have mixed a batch up. Using the squeeze bottle, apply enough to soak the sand. Once you do, the sand will settle a little. Have your sand bottle ready to apply a little more sand if necessary. Add a little more Xtreme Set and you are done!
We came back 20 minutes later with our 4” turbo cup grinding wheel and ground the repairs flush. The polyurea and sand made for a great repair. It was amazing how fast and easy this really was!
As you can see, these repairs turned out great! Professional quality concrete crack repairs like these help to ensure that the repairs will not telegraph through the coating. Xtreme Set 100 is by far the best crack repair and concrete joint filler for garage floors we have used.
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Purchase Xtreme Set 100
Xtreme Set 100 can be purchased from Legacy Industrial. They now have a 32-ounce option for smaller repairs. 1-gallon and 2-gallon options are also available.
Something else you need to be aware of is that the squeeze bottles do not come with the Xtreme Set 100. You will need to purchase them separately. You can find them here at Amazon.
In addition, separate color tint packets are now available. These come in handy if you want to color-match or add contrast when filling joints for color-stained or decorative concrete that will receive a clear coating.
Tips when using xtreme Set 100
When we said that Xtreme Set 100 was fast, we were not kidding. All cracks and small repairs should be filled with sand before you mix the polyurea. Also, make sure not to mix much more than what is needed for the repairs. If you mix too much it will be wasted.
We had one of our concrete test pavers ready when we mixed the first batch and applied it. We took a few minutes to take pictures and then we applied sand to the second concrete repair paver. When we attempted to apply the Xtreme Set 100 to the second concrete repair, it had already begun to set up and could not be used. In fact, it got quite warm from the thermosetting reaction. We quickly learned that you need to be prepared and ready to go.
Final Thoughts
Xtreme Set 100 by Legacy Industrial can truly save you time and man hours. Contraction joints for a typical 2-car garage can easily be filled and ground flush in as little as 30 minutes or so. Multiple garage floor cracks can be repaired just as quickly.
The cost doesn’t justify the ease of filling a couple of small cracks. However, it’s an excellent option for garage floors with larger cracks or multiple cracks that need repair.
Give Legacy Industrial a call or email them if you have any questions. Their customer service is good and they are great at working with the DIY crowd. If you are looking for a fast and easy solution to concrete crack repairs and small patch repairs, you will surely be impressed with this product.
I would like to purchase 2 gal of extreme set 100 to apply to Styrofoam with a
cloth or glass matt. I work at a zoo and make sculptures and artificial rock.
this product might be what I have been searching for. If it works for me, I will buy a lot of it.
We recommend that you give Scotty at Legacy Industrial a call and ask him about that type of application Phillip. I’m not so sure the polyurea would be friendly to the Styrofoam.
Shea: A few of your readers (and you) let me know the bottles were out of reach , cost wise. I wanted to let you and your readers know that we reduced the bottle price down to approx 4.00 per bottle. Thanks for the feedback! -Scotty, Legacy Industrial.
Wow, that’s great news Scotty! We will make an update to our article as well so readers will be aware.
Hi, thank you for the information. I am planning to purchase this to fill the contraction joints in my garage concrete before putting the epoxy. My question is do I grind the floor in preparation for the coating or fill the joint first?
Hello Jun. Fill the joints first then grind them flush when you grind the floor.
How much product is required to fill contraction joints for a 4 car garage, approx 900 sq feet?
Hello Jen. Legacy Industrial’s technical date sheet states: “One Gallon Unit, when mixed with silica sand, will fill a void 300 lineal feet ½” x ½””. Just total up the length of all your contraction joints and divide that number by 300. That will give you a rough idea of how many gallon units that you need.
I am applying this product to a new slab. I am going to etch with muratic acid. Should I etch before or after filling the joints? Thank you for a very informative site!
Hi Morgan. It really doesn’t matter. You can etch first, fill the joints and then grind them flush. Or you can fill the joints, grind them flush, and then the acid etching will help remove the remaining dust on the concrete from grinding.
I have an older concrete slab garage that does not have contraction joints, and probably as a result has a healthy horizontal crack across the slab. The floor has been sealed. I am planning to epoxy. My original thought was to repair all the cracks with Xtreme 100, then grind entire floor, then epoxy coat. Is this product good for all my cracks? The rest of the cracks are relatively small.
Should i grind first?
Hi Michael. Xtreme Set 100 is an excellent choice for that. Because it sets so quickly, you can grind first to expose any concrete cracks and irregularities, apply the Extreme Set, and then grind those areas flush 20-30 minutes later.
I have some cracks but I have some type of Crack filler already in them. Some didn’t work very well. So i had to clean that and now I’m wondering if ii will mix right with the other crack filler. I also want to know if this will be a problem with Purepoxy PE-100 (top Coat) Metallic.
Hi Nery. As long as you have removed any loose or old crack filler that is not adhered well, Xtreme Set 100 will work fine. Like all repairs, you need to grind it flush so the new coating will adhere and repairs do not telegraph through.
Is Extreme Set 100 paintable?
Yes, it’s paintable, Beau.
I finished applying this product, and I’m not seeing the same results that I saw in the videos. Wondering what I may have done wrong. I have a few spots where the sand and chemicals have turned a white color, but the majority of the joints just look like the sand is wet with no reaction going on.
Hi Mike. There shouldn’t be a reaction unless you mean how it cured. The sand and polyurea should turn very hard in 20 minutes. Has it done that? If not, did you properly mix the two parts of the polyurea and shake it up well in the bottle?
Hi Shea, thanks for the reply. Yes I properly mixed and shook. It is all very hardened. I was just wondering if there was a reason some spots turned white and others did not. The spots that did not turn white look like wet sand. Still hardened though.
OK, that’s a good thing, Mike. The sand looking wet is fairly normal. The white spots may be from trapped air or the sand being slightly damp before the polyurea. Either way, it should not be a problem.
I didn’t read the whole process of the sand and I just applied the extreme set 100 into the cracks without the sand. Does it matter if it doesn’t have sand other than taking a lot more extreme set to fill it?
Hello Andrew. No, it’s not a problem. The job of the sand is to act as filler in order to stretch out the Xtreme Set. You will be fine.