What is the primary reason to sand surfaces before painting?

Sanding surfaces before painting is primarily done to create a smooth surface and improve adhesion. When a surface is sanded, it helps to remove imperfections, old paint, or contaminants that may prevent the new layer of paint from adhering properly. A smooth, properly prepared surface allows the paint to bond more effectively, leading to a more durable and aesthetically pleasing finish.

This process minimizes the risk of issues such as peeling or bubbling that can occur if the paint doesn’t adhere well. Additionally, the fine scratches created by sanding provide a “tooth” for the paint to grip onto, further enhancing the adhesion quality.

While changing the color, removing old paint completely, or adding texture to the surface might be considerations in different contexts, they are not the primary reasons for sanding prior to applying a new coat of paint. Proper surface preparation through sanding is essential for achieving the best results in any painting project.