General Plastics is utilizing our 78 years of experience to help frontline caregivers. Our high quality soft, flexible polyurethane foam strips are used to manufacture Personal Protective Equipment such as face shields and masks. Please click here to learn more.

Local: (800) 806.6051
International: (253) 473.5000
Request a quote


Download Doors & Windows Flyer

Take advantage of the unique chemistry in General Plastics’ LAST-A-FOAM® for your door and window applications. Our rigid polyurethane foam has been proven to perform, providing you with material that is long-lasting, durable and satisfies the qualities needed for skilled craftsmanship.

All LAST-A-FOAM® polyurethane foam is formulated so it remains dimensionally stable and will not warp or bow. Due to its closed cell structure, our foams have high resistance to water absorption, and will not swell or crack when exposed to moisture. It has also been proven to retain its physical properties in long-term applications.

As core material for entry or interior doors and garage doors, LAST-A-FOAM® polyurethane foam is an ideal substitute for wood due its resistance to rot, fire and water. It’s also an alternative to medium-density fiberboard (MDF) due to its strength, lighter weight, and higher insulation values. For example, the LAST-A-FOAM® FR-4600, our microcellular foam with the finest cell surface, can support window trim applications with intricate and 3-dimensional details.

LAST-A-FOAM® adheres well to composite skins, and it may also be used without adhesive when bonding, for example, when curing pre-impregnated skin together with a lower density foam or molding a cured composite skin to the foam material. We offer several products that come in a wide range of densities (3 to 50 pounds per cubic foot) allowing you to choose the mechanical properties appropriate for your application, whether it be strength requirements, fire-retardant properties, machinability, grain detail, or surface finish.

LAST-A-FOAM® can be provided in sheets and blocks or molded. When molded, exceptional grain detail mimicking the look of wood can be achieved.

Choose LAST-A-FOAM® polyurethane foam for material that is strong, consistent and supports your finishing techniques.


  • Lightweight, strong and durable
  • Wide range of products for various density and strength requirements
  • Adheres well to composite skins, wood, and engineered wood products
  • Does not absorb water and does not warp
  • Grain-free, fine-cell surface for intricate details, painted finishes, better machining and processing
  • Significant weight savings compared to other materials
  • Accommodates virtually any resin and coating system
  • Compatible with many types of adhesives


  • Window trims
  • Insulated garage doors
  • Insulated entry doors
  • Interior doors
  • Decorative feature for doors and windows


Use our Product Finder tool to find out what product is suitable for your specific application.

Ask For More Info

Related Resources


Inside Composites Interview with General Plastics President & CEO, Dr. Mitchell Johnson

Read More

Technical Papers

Composite Core: Factors to Consider When Choosing Core Material for Your Application

Read More