High-density polyurethane (HDU) is a rigid, closed-cell foam made by combining polyurethane resin with a blowing agent. This causes the mixture to expand into a foam that is then shaped into sheets or blocks. Compared to materials like Styrofoam, HDU is denser and more robust, making it versatile for various designs and treatments.
HDU is manufactured specifically for signs. It is waterproof and resistant to petroleum solvents. The material won’t warp, crack, bow, or rot like wood when exposed to elements, making it an excellent choice for outdoor uses.
Working with HDU
- Can be sandblasted, routed, carved by hand or CNC
- Textures such as wood grain can be simulated with textured frames
- V-cut or V-grooved letters give an etched look
- The material can be routed to look like raised letters
HDU offers a 10-year warranty against deterioration, warping, and cracking, whether used indoors or outdoors. It’s 100% waterproof and unaffected by temperature, making it preferable for most sign projects, especially large outdoor installations.
The Durability of HDU Signs
Outdoor signs made from HDU can generally last about 8-10 years. For a smooth finish, signs are prepped with a high build acrylic primer followed by an automotive primer, then sanded and finished with paint. HDU signs are available in different thicknesses for a variety of needs, and they hold up extremely well in any weather condition.
Precision Board HDU, due to its ease of use and the fact that it doesn’t absorb moisture, rot, or warp, is particularly effective for signs. Our signs manufactured out of HDU give the appearance of redwood but provide more durability and longevity.