The present invention includes a set of reinforcement and support devices for existing or new roof, ceiling and/or floor systems together with numerous variations that may be installed into existing buildings or new buildings to help prevent separation of wood or metal roof, ceiling and/or floor systems from the concrete, masonry or other types of walls supporting these systems in commercial, industrial and/or residential buildings. One embodiment includes a set of three brackets that are installed in a triangularly shaped arrangement along a side of a primary support beam and to the wall underneath a ledger, thus anchoring the support beam to the wall of the structure and stabilizing the roof, ceiling or floor it supports. Another embodiment includes a single integrated unit that attaches to the wall underneath the ledger and to an adjacent support board, thus anchoring the support board (and the system it supports) to the wall of the structure. Another embodiment includes an angle iron with predrilled holes that attaches through the ledger directly to the wall to reinforce the ledger and extend the area of horizontal support provided by the ledger. Other embodiments provide support structures that may be attached and arranged to provide specific structural support at designated locations, and/or to provide wall-to-wall structural support across the span of a roof, ceiling or floor. All embodiments may be adapted for use with ceilings, roofs or floors.