What Causes Paint to Go on Unevenly When Using a Roller?

Too Much Paint

• Too much paint on a roller results in buildup and drips as well as wasted paint. When repeatedly dipped in too much paint, the roller edges develop a buildup of paint, creating a defined edge from where you placed your strokes. A rolling pan is a useful tool for preventing a buildup of paint. Use one for every color you are applying. After dipping the roller into the paint, roll it over the pan to remove the excess paint. Paint the wall in even strokes, in an up and down fashion in the form of a W.
  
  

Not Enough Paint

• Uneven paint is also caused by not having enough paint on the roller. The color does not apply evenly and you end up with a splotchy covering as well as spots where the original paint is still visible. To prevent a spotty paint job, fully dip the roller into the paint and thoroughly turn it over a rolling pan until paint no longer drips off of it.
  
  

Dry Edges

• You create an edge of paint when you apply it to a surface. The edge makes clear where you started painting with a roller and where you stopped. Dry edges occur when you apply paint to a surface, let it dry and then come back and reapply paint over the dry edge. If you paint over a dry edge, you will see your paint roller strokes. Avoid dry edges by quickly applying the paint to the surface and always painting over wet edges.
  
  

Use the Correct Rollers

• Cheap rollers are not always the best option to use when painting. Compared to high quality brands, cheap rollers fall apart more easily and do not hold as much paint, which means having to take more time to dip and use the rolling pan repeatedly. Selecting the correct roller depends on what type of surface you are painting. Use the appropriate nap, which refers to the length of the material on the roller, for even paint coatings. For instance, a 1/4- inch nap is best used on smooth surfaces whereas longer naps, such as 3/4-inch, is used on rough surfaces like concrete.
  
  

Bumpy and Unprepared Surfaces

• Bumpy and unprepared surfaces are a common reason why paint looks uneven when applied. Bumpy surfaces and damaged areas need to be repaired before paint is applied. Paint spreads better and more even over smooth surfaces. Unprepared surfaces, such as non-primered spackle, absorb paint differently than other surfaces and leave dull spots. Always prepare a painting surface with primer or, if primer is unnecessary, as with painting over a flat finish, wash the area with soap and water.