- The orange peel effect may reduce the hiding power of the coating as the previous color of the surface can be seen in the hollow spaces of the texture. This is more noticeable when applying a darker color.
- The level of quality (economical, general use, professional use, high-end) has a direct influence on this. A higher-quality nap is thicker and, therefore, holds and releases paint more efficiently than does a lower-quality nap.
- Woven naps tend to unravel after they have been washed a few times, except for high-quality roller covers.
- Use a roller cover of at least 10 mm for water-based coating applications on walls and at least 13 mm on ceilings.
- Do not use a roller cover over 10 mm for solvent-based coating applications on walls and doors (to avoid running).
There are two types of frames: the 4- or 5-prong frame and the single shaft frame with plastic tips or nuts. The 4- or 5-prong frame is mostly recommended because the prongs firmly hold the cover on the whole frame length. It is also more practical since you simply need to slip the roller covers on or off the frame. Then again, sophisticated single shaft frames are available on the market.
Handles come in wood or plastic and most are threaded to accommodate extensions. A plastic handle is a better choice because the threads of wooden handles swell and get damaged when rollers are cleaned with water.
The most commonly used rollers are 190 and 240 mm wide (7 1/2" and 9 1/2"). They are great for large flat surfaces. The 240-mm rollers get the work done faster, but they are heavier.
Special rollers are also available for particular uses. Some rollers are designed to paint in corners. The 3" rollers are used to paint narrow surfaces such as woodwork and doors. Pipe rollers adapt to the shape of heating pipes.