from $1,227.96 /pallet
from $1,227.96 /pallet
WD40 in stock in OR and CT - other thicknesses lead time approximately 6-7 weeks

Product Specifications


Highly compression resistant wood fiberboard insulation for floors, walls, ceilings and roofs. Can be used in facades and fully sheathed roofs in rainscreen application when protected by ProClima WRB or roof underlayment


THERMOSAFE-WD 40: 43 5/16" x 23 5/8” x 1 9/16” thick, 796 sf

Custom dimensions available


  • Biologically safe (natureplus® certified- biologically save, carbon sequestering insulation that is vapor open
  • High thermal mass, allows product to protect interior from solar heat in summer. Highly sound absorbing
  • Raw material for all GUTEX insulation boards comes solely from wood that is harvested and grown using sustained forestry management practices
  • Boards are made using the dry process meaning that the boards contain 96% wood, and maximizes the use of this sustainable, recyclable natural resource
  • When used as insulation in exterior walls or roofs, THERMOSAFE WD needs protection by WRB (Pro Clima MENTO Membranes) or cover board by GUTEX cover boards (MULTIPLEX TOP, ULTRATHERM, THERMOWALL or MULTITHERM)


  • R-value/in: R- 3.6 per inch (U-value 0.039 W/mK)
  • THERMOSAFE-WD 40 Board R-value: 5.8
  • Custom orders in bulk possible for other thicknesses
  • Perm rating: 44/inch (Sd 0.24m for 40 mm board)