What is fiberglass mesh?

Question:i was reviewing the proposal for the waterproofing of my firewall in the building...this one proposal said they will place fiberglass mesh on the entire firewall...i dont know much, is this recommendable or will it create a bigger problem in the long run? pls advise.

Answers:
Fiberglass mesh is a reinforcing layer that is used to bond and strengthen the two layers of waterproofing. The tar compound will dry and shrink as it ages and the mesh will ensure that the tar will not crack through both layers and lose it's waterproofing ability. It also serves to tie the layers together to eliminate separation. Some installers will apply the first layer of tar and the mesh then nail through the mesh into the wall to further eliminate the chance for separation before applying the second layer of tar.