foamboard

Foamboard, also known as foam core board, is a lightweight composite material used for mounting, displays, and crafts. It consists of a rigid foam core—commonly polystyrene or sometimes polyethylene—sandwiched between two outer facings of paper or cardstock. The facings provide a smooth, printable surface and contribute to overall rigidity. Thicknesses typically range from 3 mm to 12 mm, with 6 mm and 10 mm being common; sheet sizes vary by region, often around 20x30 inches or 24x36 inches.

Manufacture: The foam core is produced by extruding or casting foam, then sandwiching it between facings on continuous rollers. The resulting boards are cut to size and sometimes coated or laminated for moisture resistance or to accept printing.

Applications: Foamboard is widely used for mounting photographs and prints, making presentation boards, signage, architectural or product models, and craft projects. It is favored for its light weight, rigidity, and easy workability; it can be cut, drilled, or shaped with standard craft tools, and accepts adhesives and laminates.

Limitations: It is susceptible to moisture and may warp when exposed to high humidity or water; the surface can dent from impact; it is not suitable for outdoor use unless specially coated; adhesive choices should avoid solvents that dissolve polystyrene.

Variants: Foam board is distinct from high-density foam boards such as Gatorfoam (wood fiber core with resin-coated outer faces) and PVC foam board, which offer greater durability or water resistance. In signage and display contexts, foamboard remains a cost-effective option for temporary or indoor use.