The back sidewalk is constructed of Oklahoma Thin flagstones. While they are cemented in place, they still need to be grouted between the stones. We did this when it was built in 2006, extended in 2014 and when it was refreshed in 2021, and it looks to be needing it again.
We begin by pressure washing the sidewalk, to clean out anything between the stones.
Then we applied the same Polymeric sand. Tan. Bought from Home Depot. Techniseal EZsand. This is just poured on, and then swept into place.
and then wet down with the "Mist" setting on the hose.
Once it was all dry (several sunny days), we bought some waterproofing sealer from Home Depot (SealKrete Original)
and used to hand-held pump sprayer to spray this on all the seams, in an attempt to seal them against the elements, leading to a longer time until this has to be done yet again.
We also tried a different approach on the section of the sidewalk by the garage, and around behind the raised garden. On this section, instead of using the Polymeric sand, we just poured mortar mix. We used the broom to again sweep it into all the cracks between the stones, and then the mist setting on the house to spray it down. The hope here is that the mortar mix, being harder and more rigid, will fill and seal the space between the stones, and stay there. So we will not need to replace it again. Time will tell.
