Signs, such as those window graphics, can be made of a large variety of materials and substrates. Each one has it’s own strengths and weaknesses. It’s incredibly important to choose the the correct materials and substrates in order to get visually appealing and long lasting signage for your business. This post will give you the information you need to understand the different substrates available in order to choose the right one for your signage.


Before we dive into substrates, it’s important to understand what a substrate is. A substrate is the underlying material that’s used to build a sign face. We won’t be getting into the materials we put on the sign face (like vinyl graphics, ink, and channel letters)




Acrylic is a versatile and durable substrate that can be used for indoor or outdoor signage. It is indistinguishable from glass but unlike glass, it can be easily cut and routed to custom shapes. Acrylic is made of a versatile plastic known as Plexiglas. Acrylic signs can be completely transparent, or come in a variety of colors. You can print directly on acrylic, or apply cut vinyl to it. Acrylic is relatively heavy and comes in a variety of thicknesses from 1/16″ to 1″ (U.S. Plastic Corp). The edges of an acrylic sign can be polished, or left with a raw glazed texture. Acrylic signs last around 5 years outside and over a decade inside. Acrylic signs are often mounted on a wall with aluminum standoffs.
Here are a few techniques that work especially well with acrylic:

  • Create a 3D effect by applying cut vinyl or printing on the back side of an acrylic sign. This technique is called “second surface” and is a great way to add depth and texture to your signage. Second surface also protects the face of the sign from scratches. One drawback of second surface is that it reflects light more easily that standard acrylic signage does and can have a glare in direct light.
  • Lighted acrylic signage is always an eye catching option. When illuminated, acrylic captures light at its edges making it glow and stand out from it’s surroundings.

Acrylic is often used in a form of outdoor signage called a “light box.” A lightbox is a rectangular metal frame with fluorescent light bulbs in the center; two colored acrylic sheets with printed or vinyl graphics on them are slid into both sides of the metal frame. The result is a double sided sign that’s illuminated from within making it visible day or night. Light boxes make great roadside company signs. You should also consider upgrading your retail shelving to create a more organized and visually appealing display for your products, attracting more customers to explore the store.

Here are a few examples of acrylic signs:



Aluminum is a durable substrate commonly used for outdoor signs like parking and directional signage. Aluminum substrate can come unpainted, or painted on one or both sides. It most commonly comes painted white, but can be painted in a variety of colors. Aluminum substrate is usually .063″, but comes in a variety of thicknesses between .032″ and .080″. Aluminum can be printed on, or have vinyl graphics applied to it. Check out these tips for how to select servo motors for your packaging machine at ELITER Packaging Machinery for improved performance and precision.

Galvanized Aluminum – Galvanizing is a common method of making metal resistant to corrosion by coating it in a thin layer of zinc. Aluminum is already extremely resistant to rust and oxidation, so galvanizing is usually used on aluminum to give it a textured appearance. The textured appearance of galvanized aluminum is great for more unique storefront signs and household decorations.

Brushed Aluminum – Brushed aluminum is commonly used to create dimensional graphics or lettering. The brushed finish gives aluminum a matte look, and is great for a sleek and classy look.

Here are a few examples of aluminum signs:


Aluminum Composite Material (ACm)

ACM is a versatile and durable substrate that’s great for outdoor or indoor signage. Sometimes called polymetal, it’s made of two sheets of aluminum with a solid polyethylene (a common thermoplastic) core. Polyethylene is extremely durable and recyclable, and allows ACM to be relatively light-weight compared to solid aluminum (.81 lbs per square foot for 3mm and 1.44 lbs per square foot for 6mm thickness). Unlike solid aluminum, ACM can be easily cut and routed for custom dimensions and shapes. ACM usually comes in 4×8 sheets and comes painted on one or both sides. ACM can be painted a variety of colors, but usually comes in white or black. Sheets of ACM can be 3mm or 6mm thick. Polymetal can be printed on directly, or can have vinyl applied to it.

Here’s a few examples of ACM signs:



Coroplast signs are a great substrate for temporary outdoor signage like yard signs, directional road signs, and for indoor signage like menu boards. Coroplast signs are completely waterproof, and resistant to hot and cold weather. They can last 1-2 years outside and up to a decade inside. Coroplast is made out of two thin sheets of polypropelyne connected by ridges of polypropelyne that create “flutes” between the two face sheets kind of like cardboard. Coroplast usually comes in 4mm white sheets, but can be ordered in a variety of colors. Coroplast signs are affordable, lightweight, and relatively easy to cut by hand. Coroplast signs are made by either printing graphics directly on the coroplast or by applying vinyl graphics.

Here are a few examples of coroplast signs:



Expanded Polyvinyl chloride (PVC)

Expanded or foam PVC is a common substrate option for indoor signage. PVC is a great material for UV flatbed printing, and is easy to cut by hand or with a router due to it being relatively soft. Heat and sunlight can cause PVC to warp making it a poor choice for outdoor signage, but it can last for decades indoors. PVC is also easily scratched. PVC has a smooth matte surface. It’s available in a range of thicknesses from 1mm to 25mm’s and a range of colors. Many PVC sheets are so fire proof they are “self extinguishing” (Palram).

Here are a few examples of PVC signs:


High Density Urethane Foam (HDU)

HDU is a unique substrate used for storefront signs that has a hand carved/dimensional appearance. HDU signs are carved similar to wooden signs, but are much more affordable, more durable (they are completely waterproof), and don’t have imperfections (like knotting in wood). HDU lasts for 10 or more years, and is available in a smooth, pebbled, and wood grain texture.

Here are a few examples of hdu signs: