BIBS is simply a Blow-In-Blanket-System of using recycled fiberglass inside walls and attic spaces where there are no gaps in the floor boards or where the attic is sealed. Most green builders used spray in cellulose at one time for insulating walls and attics, but that system introduced moisture inside the walls and could sometimes cause mold if not left to dry properly before the wall facings, such as sheetrock or plaster were put up and the wall was finished. BIBS insulation is completely dry. SIPS insulation is Structural Insulated Panel System. This system is the best to use in a green home. SIPS insulation is a type of foam board with superior R-values, which means it keeps more heat or cool air in than other insulation, and this type also makes the home much quieter than any other type of insulation. It keeps out noise from busy city streets, and keeps noise in, too, so the kids can play without driving you crazy while you try to work or do other adult things. These panels are made of recycled materials, are sturdy, and do not introduce moisture into the walls. Most green builders consider SIPS insulation an upgrade, and mostly use BIBs insulation. Ask your builder or contractor for SIPS insulation, as it is the best way to go, and is the healthiest choice for your green home.