Abstract: A modular system for containing projectiles has a sheet of material including at least a polycarbonate layer held by a metal frame having a straight frame member corresponding to each straight edge of the sheet. Each frame member has a U-shaped shield channel covering and holding a straight edge of the sheet and an adjacent U-shaped clamp channel rigidly held against the shield channel. A flexible gasket separates each sheet edge from its respective shield channel; and each frame member is fastened to each adjacent frame member only by clamps extending between adjacent clamp channels.

Abstract: A sliding door assembly includes a number of door panels slidably engaged with a track and a leader end secured to one end of the door panels. A retaining device forms a channel for receiving the leader end and has a pair of opposite resilient stops trapezoidal in cross-section and extended inwardly into the channel for engaging with the leader end and for retaining the leader end within the retaining device. The retaining device may be secured to a supporting abutment, usually a wall member, or may be secured to and moved in concert with the leader member of another sliding door subassembly for coupling the sliding door subassemblies together.

Abstract: An insulated concrete wall structure having a concrete wall with opposing wall surfaces. The concrete wall has several vertically and horizontally spaced wall ties imbedded within the concrete wall and extending between the wall surfaces. Positioned between the vertically spaced wall ties are a series of elongated retaining strips such that the retaining strips are substantially parallel to the wall surface. Insulating panels such as polystyrene foam boards are located between the horizontally spaced wall ties and retained in position by the retaining strips. In one aspect of the invention, each insulating panel has a groove formed along its vertical edge for receiving and engaging the elongated edge of the retaining strips. The present wall system is advantageous in that an insulated concrete wall can be readily formed using conventional wall forms in approximately the same amount of time as conventional uninsulated poured concrete walls.

Abstract: A recessed fixture housing in which the major components are designed with taper fits to allow the components to be pressed together in assembly to create an air-seal engagement construction. The fixture housing also provides a junction box accessible from either the room side or the attic side of a fixture, while maintaining a sealed fixture housing. Further, a recessed fixture frame for use with a housing of maximal size to be installed between building structural members with mounting bars having protruding tabs. Mounting bar brackets are inset from each frame side an amount sufficient to accommodate the tabs between the building structural member and the bracket.

Abstract: A retractable ceiling assembly for a poultry house, characterized by a ceiling which can be selectively raised from a flat to a pitched configuration in order to accommodate high-profile equipment or materials in the poultry house for cleaning, maintenance or storage purposes. In a preferred embodiment the retractable ceiling assembly is characterized by at least one ceiling unit including multiple rafter units which span the width of the poultry house in parallel, spaced-apart relationship with respect to each other. Each of the rafter units includes a pair of cross members pivotally attached to each other at substantially the middle of the rafter unit. A flexible ceiling typically constructed of overlapping sheets of fabric material is mounted on the bottom surfaces of the rafter units. A typically manually-operated winch, mounted on the interior of the poultry house roof at substantially the center of the ceiling unit, is connected to each rafter unit at the pivoting midpoint thereof by means of cables.