A wall construction, or other opaque structure of a building, includes a sequence of highly reflective insulation elements that block heat energy exchange across air spaces, combined with material insulation supporting a heat energy highly reflective surface of the highly reflective insulation element. A highly reflective insulation element is formed by enclosing an air space between surfaces, of which one or both of those surfaces is a heat energy highly reflective surface. The heat energy highly reflective surface can be provided by a layer applied to a material. In an opaque building structure, two or more such highly reflective insulation elements, using three or more heat energy highly reflective surfaces, and two or more air spaces, where the material supporting at least one of the heat energy highly reflective surfaces is a material insulator, can improve energy efficiency.

This invention relates to novel insulation and weather-resistant barrier systems, such as insulated sheathing (IS) panels sheathing panels, and more particularly insulated wall-sheathing (IWS) panels, a panel assembly comprising such panels, and systems for use in construction, such as building construction, designed to provide moisture permeable panels that protect from bulk water, excess air, and thermal transfer. More specifically, this invention relates such panel used for construction purposes, comprising an insulation layer; a structurally-stable panel, an optional fastener-gasketing adhesive layer; and a weather-resistive barrier layer; wherein, in one embodiment, the weather-resistive barrier (WRB) layer exceeds the dimension of the structurally-stable panel from at least one of its edges to create an extension flap; and wherein the extension flap of the WRB layer further comprises a removably attached release-liner on its back.

Described is a reflective insulating material for use in metal building insulation (MBI) or in post frame building insulation (PFBI) applications, the reflective insulating material comprising: a first outer layer and a second outer layer disposed parallel to one another, the first outer layer made of a reflective radiant barrier material; an insulation layer disposed between the first and second outer layers; and a fabric layer that is a scrim layer or a woven layer disposed between the first and second outer layers. The fabric layer can have various properties. A polymer seal layer can also be provided as part of the material. Processes for manufacturing the reflective insulating material are also provided.