Cement, insulation, bricks, drywall, plaster and other building materials are often times encountered in casework. They can be potential sources of evidence transfer between individuals, tools, and weapons. For example, bullets can contain trace amounts of sheetrock which may help in the shooting reconstruction of a homicide that took place in a family home. A car may have microscopic pieces of brick and mortar which can help demonstrate an impact with a building that occurred in a hit and run case. A tool containing trace amounts of wood and insulation can establish a connection between a suspect and a burglary scene.
A variety of microscopic, chemical, and instrumental techniques may be used to identify and perform comparative examinations of building materials. The microphotograph to the right is an example of characteristic needle-like crystals that form during a chemical test for sheetrock.