From cRc Kosher:
“September 4, 2018
In previous years, the cRc has recommended certain readily available fencing material (commonly sold in Home Depot) to be used for schach and provided detailed instructions on how to place them on the sukkah. However, based on feedback from consumers on the sturdiness of those materials and how they were being used, we have determined that there is a reasonable chance that some people will end up not having kosher schach (since the fencing material could become invalidated if a few of the reeds break) unless they place multiple layers of fencing on top of their sukkah.
Accordingly, we are no longer issuing specific recommendations of fencing material. Instead we suggest that if you choose to use these fencing mats that you add additional schach (e.g. added layers of these mats, bamboo poles, evergreen or other tree branches) to ensure the fulfillment of the halachic requirement of “more shade than sunlight.” Also, any fencing mats should be placed perpendicular to the schach support beams in order to avoid ma’amid issues, as we have explained in previous years. ”
(you can purchase these mats from Hayneedle for just $84.77 for a 4 pack)