Two exterior dimensional letters can be the same height but need a very different build.

A wide, bold letter can support more depth than a narrow letter with thin strokes. The wall, mounting method and material also affect the final result.

For this reason, material and thickness should not be chosen on their own. They should work with the shape of the letters and the way the sign will be installed.

Start With the Letter Shape

Many buyers first ask:

Should we use aluminum, acrylic or PVC?

A better place to start is the letter shape.

Letter height matters, but it is only one part of the decision. Stroke width, small details and narrow sections can affect how the letters are cut and mounted.

For example, two 18-inch letters may look similar on a drawing. But a bold font has more space for mounting points than a narrow script font.

Before choosing the material, look at:

• letter height;
• stroke width;
• small details;
• required depth;
• mounting points.

A thicker letter is not always a better letter.

How Thickness Changes the Look

Thickness affects how the sign looks from the side.

A thin flat-cut letter can look clean from the front. However, the 3D effect may be weak when people see it from an angle.

A deeper letter creates a stronger side profile. But too much depth can make narrow letters look heavy.

It is also important to separate letter thickness from standoff distance.

Letter thickness is the depth of the letter itself.

A standoff moves the whole letter away from the wall. This creates more space and more shadow.

These two methods can create very different results. A larger standoff does not always replace the need for a thicker letter.

Aluminum, Acrylic or PVC?

There is no single best material for every exterior dimensional letter sign.

Aluminum works well for many outdoor signs. It can have a painted or metal finish and can also support several mounting methods.

Acrylic gives a smooth and clean look. Its edge can also become part of the design when the letters are seen from the side.

PVC is light and easy to cut. However, the outdoor environment, size and finish should be checked before using it instead of metal or acrylic.

The main question is not:

Which material is best?

The better question is:

Which material can give the right depth and mounting method for this letter design?

Mounting Can Change the Material Choice

Mounting should be reviewed before production starts.

Stud-mounted letters need enough material behind the letter for secure mounting points.

This can be harder with thin strokes or small details.

The wall also affects the decision. Brick, concrete and ACM panels do not use the same mounting approach.

The sign manufacturer can prepare the letter and mounting interface. However, final installation and site-specific attachment should be checked by the local installer or engineer.

This keeps the letter design practical before fabrication begins.

When Flat-Cut Letters Are Not Enough

Sometimes adding more thickness is not the right answer.

If the project needs a much deeper side profile, a larger 3D form or internal lighting, fabricated letters may be a better option.

For signs that need strong night visibility, channel letters for storefront signs use a different type of construction.

Grandview also produces custom LED channel letters for projects that need internal lighting.

So the key question is not:

How thick can we make the letter?

It is:

Does flat-cut construction still suit the design?

If the answer is yes, material and depth can be adjusted together.

If not, a fabricated letter may give more control over depth and lighting.

FAQ

Are thicker dimensional letters always better outdoors?

No. More thickness creates a stronger side profile, but too much depth can make some letters look heavy. The right depth depends on the letter shape, material and mounting method.

Are dimensional letters the same as channel letters?

No. Dimensional letters are often solid or flat-cut. Channel letters have a built-up body and can hold internal lighting.

You can also read our guide to custom channel letter fabrication for more detail.

Grandview can review the proposed letter construction and manufacture the letters to approved project drawings.