Core Types

The backbone of every door.

Oshkosh Door Company offers non-rated, fire rated, and specialty cores to meet the specific demands of nearly every environment.

The Window and Door Manufacturers Association (WDMA) has developed performance standards for architectural grade wood doors determined by duty levels. The duty levels are based on the amount and severity of use. Here are some examples of applications for each duty level:

Standard duty: Low usage office doors, closets, or private restrooms
Heavy duty: Assisted living, office entries, or medical exam rooms
Extra heavy duty: Classrooms, hospital patient rooms, or dorm rooms

Find out more information on LEED® credit and FSC® requirements compliant standards.

View our acoustical and STC rated cores here.

Find our CorGuard FRP core types here.

Non-Rated

The standard in everyday strength.

Find the exact specifications your project demands. Most can be used in a 20-minute fire rated application.

GP

  • Particleboard core available in standard duty, unblocked heavy duty or extra heavy duty with blocking
  • ANSI A208.1 grade 1-LD-2 (32 lb.) and LEED® compliant MR 4 (recycled content)

GPF

  • Particleboard core extra heavy duty with no additional blocking required
  • ANSI A208.1 grade 1-LD-2 (32 lb.) and LEED® compliant for IEQ 4.4 (no added urea-formladehyde) credit and/or MR 4 (recycled content)

GPFSC

  • This particleboard core is available in extra heavy duty (no additional blocking required) and is FSC® standards compliant
  • ANSI A208.1 grade 1-LD-2 (34 lb.) and LEED compliant® IEQ 4.4 (no added urea-formaldehyde), MR 4 (recycled content, and MR 7 (FSC® Certified Wood)

GPHD

  • Particleboard core is heavy duty (no additional blocking required) and is FSC® standards compliant
  • ANSI A208.1 grade 1-LD-2 (36 lb.) and LEED compliant® IEQ 4.4 (no added urea-formaldehyde), MR 4 (recycled content, and MR 7 (FSC® Certified Wood)

GPEHD

  • Particleboard core is extra heavy duty (no additional blocking required)
  • ANSI A208.1 grade 1-LD-2 (36 lb.) and LEED compliant® IEQ 4.4 (no added urea-formaldehyde) and MR 4 (recycled content)
  • Structural Composite Lumber core is extra heavy duty (no additional blocking required)
  • 38 pcf density and LEED compliant® IEQ 4.4 (no added urea-formaldehyde)

GTFSC

  • Structural Composite Lumber core is extra heavy duty (no additional blocking required)
  • 38 pcf density and LEED compliant® IEQ 4.4 (no added urea-formaldehyde) and MR 7 (FSC® Certified Wood)
Fire Rated Cores

GFREM

  • Non-combustible mineral core
  • LEED v3 and v4 compliant

GFAPB45

  • Agri fiber core in standard duty, heavy duty or extra heavy duty with blocking
  • LEED v3 and v4 compliant

GFAPB60

  • Agri fiber core in standard duty, heavy duty or extra heavy duty with blocking
  • LEED v3 and v4 compliant

GFSCL

  • Structural composite lumber core is extra heavy duty (no additional blocking required)
  • LEED v3 and v4 compliant
Specialty Cores

GLL

  • Designed for environments requiring radiation transfer protection
  • Particleboard core (20 minute rating) or fire rated with 45 or 60 minute radiation resistant (LSL available)
  • Optional constructions can be compliant with FSC® or LEED® credit requirements

GBR

  • Designed for environments requiring extra safety. Bullet resistant core materials tested and labeled per UL 752
  • LEED compliant IEQ 4.4 (no added urea-formaldehyde)

GA

  • A variety of acoustical rated cores are available to meet different STC rating standards. Click above to view the complete listings.