01-25-2018, 02:46 PM
(01-21-2018, 09:43 PM)JDuke Wrote: Just saw an advertisement for sika post fix (quick google search will find several videos)
It's essentially a 2 part foam product sold at big box stores to set posts instead of quikcrete.
It says one bag replaces 2 50lb bags
Looks like it's about 50% more expensive than quikcrete.
I know that foam is a great product for insulation, and I know a guy who's business is leveling concrete pumping foam under it.
I'm curious what the longevity and stability of the post would be.
It would be more expensive than quikcrete, but would be lighter to carry around. Other than that, I don't see much benefit.
I also wonder if the ground was water saturated if the post might float.
Duke
One more post script, if making foam expand is as easy as mixing it in a bag, why isn't there a homeowner kit for spray foam?
I put in a fence a couple years ago and splurged on Sika Post Fix for all the holes (~30 of them). Definitely cost more than concrete but holy cow did it go blazingly fast to get all the posts set in one afternoon with no back-breaking concrete handling. You crush the bag like a hand warmer, rapidly mix for something like 30 seconds, open it and pour. Hold the post in position for about 3 minutes and move on. An hour or so later you're hanging panels on it.
As far as I can tell so far this stuff is as awesome as advertised. It forms a very hard, water-tight seal around the post yet it has some compressive "give" whereas concrete doesn't. I put one in the wrong spot and the next day it was very hard for me to remove it. Over a winter there was an extreme wind storm, neighbors had fence posts snap off at the base. Mine held strong, likely in part because the hardened foam does have some "give" to it when such shearing forces were applied. It's only been a couple years but I see no sign of degradation. As well, in the lower back part of my yard it can get very wet - standing water in some spots and so far I've not seen any of the holes move or float. At that time (a couple years ago) I had found some guy on the internet who had a blog post about using it, and I reached out to him and he wrote back, saying it had been 6 or so years for him at that point and his experience was the same.