Sika Postfix Fence Post Mix, Mix-in-The-Bag Expanding Foam for Supporting Non-Structural Posts, Fence, Mailbox, and Sign Posts

Used this stuff for the first time tonight and I doubt I will buy another bag of concrete again. Have your hole dug out and ready. READ the instructions on the bag. Now here's the hard part - FOLLOW the instructions on the bag. If the temperature isn't right outside, WAIT until it is. Once you roll up the bottom part into the top part of the bag, the material will activate QUICKLY. I had enough time to mix the bag over my leg - shoe shine style - 5 or 6 times. Once the two sides are mixed, you have about 15 seconds and the bag WILL get hot. (Chemical reactions do that!) Have some scissors ready to cut open the corner of the bag as it shows you in the picture and pour out the mixture QUICKLY. It pours out like a liquid but it turns into a foam material... and it will expand QUICKLY. I popped in my new mailbox post, put a level on the top to make sure it was straight, and within 3 minutes I could let go and the post was standing on its own. The hole I dug out has been filled and is overflowing the top. I'm going to wait 24 hours and then take my saw-zaw out there and cut away the excess. *** For those of you concerned about the material bursting out of the sides of the bag, use some heavy packaging or duct tape and put a 2nd layer on both the left and right sides of the bag. Mine didn't burst, but I used it anyway because I saw other reviewers complain. Potential problem solved! *** And if you aren't going to use all of it, have a garbage bag outside with you to throw it in... because this stuff can get messy. YES it's more expensive than your local retail store, but duh Amazon is going to deliver it to you! This stuff helped me finish replacing a mailbox post in less than an hour. I highly recommend it and will buy this Sika product again!

I bought this product after seeing a video on Instagram about installing an umbrella in a planter, and if you've seen it, it works. The only issue was a lack of practicality, which caused the product to splash onto my husband's pants, and we had to throw them away. It also got on his arm, but with hot water and soap, it came off in a couple of days without any problem.Additionally, it was the best solution for a low drawer in the kitchen that I couldn't use because of its depth.

I used this foam to install a post for a mailbox this weekend. It worked great! The process was easy and the post seems to be held firmly in the ground. Time will tell if it continues to work long-term but everything is great now.

Works great!

I am a 67 year old female and needed to have a sturdy pole placed in the ground for a weather station. I am past carrying 70 pound bags of concrete around and was searching online and found this. Super easy to use…cool to watch. Hardens really quickly, been in the ground a few months now and has not moved or shifted. Advice, make sure that you follow directions about the depth of the hole. I was about 2” shy of what they recommended and it did mound about 2” above ground. Stuff is good enough that I did re-purchase for my next project.UPDATE: it is now well past the horrible AZ summer we had this year and now into very cool nights. I have noticed zero change in how strong this stuff is. Super satisfied. Putting in a post for a motion camera and cannot wait…the stuff is so cool to watch.

I bought this product because one of my fence posts had rotted off. I just needed to replace that one and it was winter time so I didn’t want to use concrete and have it not set correctly. I would not recommend using this product if it is a permanent fence. This is just a quick fix. I am not sure how long this will hold up as The foam is already pulling away from the post.

First I must say, it works! We used one bag on 2 fence posts that were leaning in our horses' paddock . After pulling the posts back into position with our tractor we were ready to pour. READ DIRECTIONS carefully, and be ready - we used on an 80 degree day, and never got to the "cut open" step because it activated so quickly once mixed, that it popped open & began bubbling out. That's why it's imperative that you are in position over the hole when you start kneading and mixing in the bag. And don't skip the goggles and protective gloves. Result was exceptional. Set up quickly, and we left it for half an hour before untying tractor ties, and voila! Sturdy as can be. I gave it a 3 of 5 for value because I did find that you can purchase it cheaper through Home Depot or Lowes, @ $13.99 vs $23.99 here. Would highly recommend the product- way easier than mixing concrete, and virtually no set up time.

Had to have broken post replaced. Handyman that came to repair it had never used this product and neither had I. We had a backup plan in case it wasn't what we thought. He followed the instructions and sure enough the foam rose up. It had to set and because he couldn't wait around 2 hours he came back the next day. We were both anxious to see how it worked. he cut the excess off and tested the post. Was as amazed as I was. He now has the name of a product he can use in his work!