Polyisocyanurate Unfaced Boards are basically rigid foam board and are combined and produced from different materials like asphalt fiberboard, polystyrene, polyurethane and polyisocyanurate. Definition of polyisocyanurate foam is little bit difficult, but basically its plastic form where two different kinds of liquids isocyanurate and polyol are mixed together.

Its most commonly used as in foundations, exterior walls and roofs to insulate with very durable and flecible surface and thermal insulation. Polyisocyanurate Unfaced Boards are unfinished, so you have possibility to finish the surface yourself as you like. Usually there are used different coatings like foils, laminates, felts and much more.

Read also about Polyisocyanurate Foil-faced Board to study the difference between foil-faced and unfaced Polyisocyanurate boards.