Clip Bleed-Thru
Concealed fasteners, or "clips", are used in the installation of a standing seam roof system. Depending on a manufacturer's specifications, this "clip" may be any variety of thicknesses. A common type of clip seen on the market today is the 20 gauge stainless steel clip; used mostly in a industrial style building. These clips are tested and approved by a manufacturer to give you better performance ratings such as a wind uplift test.
When you are dealing with a standing seam roof panel, no matter of the material that it is made of, a uniform and consistence seam is always desired. However, in most all cases, there will be an imprint of the clip that can be seen after the panel has been seamed with a roof seamer through the process of roll forming. This is a very common occurrence and is considered acceptable.
For example, let's say that you are working with a 22 gauge steel roof panel paired with a 20 gauge floating high clip. When you install these two on a roof system together and look down the seamed rib, you will be able to see the imprint of each of the clips. This is referred to as "clip bleed-thru".
This happens because you are trying to conceal either an equal or greater amount of material under a thinner surface. We can accommodate this occurrence to a certain degree by adjusting the seamer to form a looser finished seam profile. This will form a uniform seam between the clips and reduce the amount of clip bleed-thru when the seamer encounters a clip. Sometimes if the profile is loosened, it may adversely affect the ratings or warranty. You will have to refer to your jobsite inspector or panel manufacturer for additional specifications that may be required by the architect or more information.