Warmboard is a highly effective internal insulation solution for new and existing builds. It features an insulated panel of Xtratherm PIR insulation bonded to 12.5mm plasterboard. This product is also known as Warmboards. It is used to improve the thermal performance of walls in new build and refurbishment projects by internal lining. The 8ft x 4ft sheet (2.4mt x 1.2mt) has a thickness of 29.5mm, including the 12.5mm plasterboard.