What is a disadvantage of reducing solvent in the primer?

The correct choice highlights that reducing solvent in the primer results in a thicker formulation. In roofing applications, the viscosity of the primer is critical for its application and performance. A thicker primer can be more challenging to apply uniformly, potentially leading to inconsistencies in coverage and effectiveness.

When the solvent content is decreased, the primer becomes more viscous, which may not spread as easily or penetrate surfaces as effectively. This can hinder the primer's ability to properly prepare the substrate for subsequent layers, impacting the overall performance of the roofing system.

While thickness is an important factor, it is also essential to consider how changes in solvent levels affect other properties, such as drying time and adhesion, but in this case, the focus is specifically on the immediate impact of reduced solvent content making the primer thicker.