Rigid foams are polyurethane materials mainly used for sealing and insulation.
They can be divided into block, one-component, spray and pourable foams. They show similar properties, but they differ in the method of application. Block foams are made by cutting a block of rigid foam into slabs with specific thickness values. One-component foams (OCFs) are the easiest ones to apply: by using an applicator directly from the can, where a reaction creating the foam occurs. The application of spray foams is similar to that of OCFs, but the main difference lies in the scale of application. Pourable foams exist as liquids which increase their volume during the application, and thus fill the gaps.