Hi everyone. will be thankful if you help me... (sorry if my english is not good) I am not in usa or canada to use best gfrc raw material. I have a big trouble here and it is weight. my gfrc weight (density) and consequently the strenght is too low. My gfrc is not dence enough and when i knock on it with my finger, the sound is like knocking on empty or poke thing, while the sound should be like…