Is there a way that I can add a texture to a surface without having it tile in the horizontal and vertical to match the other image maps being used?

I would like to add a diffuse overlay but I don't want it to tile like the bump map. Is there a way I can do this?

With iray Uber base you can adjust tiling per map - click the nano-thumbnail next to the colour property>Image Editor (not Layered Image Editor) and adjust, but note that this will apply to the image wherever it is used in the scene. A custom shader could tile different properties separately. You could also, in some cases, use a Geometry Shell in which case its surfaces will have their own tiling (and even UV) options.

Alright, I looked at Image Editor but didn't see anything that caught my attention as to where I'd do that.

Are you sure you are using Iray Uber base and are in the right Image Editor dialogue? Instance Tiling is a tab in the lower-right quadrant.

I found that yesterday after a closer look at the Image Editor, still couldn't get the image to line up right, well actually I think it did, but because I had to make it larger so it didn't tile I think it blew up the detail I wanted as well.

I figured it out! Set the base tiling to 1, then change the other image maps to the tiling I need for them so that the overlay and anything to do with it stays at what I need!

Thank you!