Rollers will leave a slight texture behind, more or less depending on the
amount of paint loaded in the roller and the type/length of nap on the
roller. Quality of the paint makes a difference as well. Personal
preference for me is a high quality latex enamel with a 3/8 nap roller. I
load the roller very heavily, go a quarter to a half of a roller width
beyond the last strip, and work it back in, floor to ceiling. On an 8'
wall, that works great and leaves a slight dimpled texture that tends to
dampen reflections and imperfections, but remains washable. To evenly
distribute the texture, start halfway up the wall with your roller.
On 20' walls, whatever method you use, there is a risk of a start/stop strip
being quite noticeable where you have painted the lower so many feet, then
got out your ladder and did the other so many feet, overlapping the lower
part slightly. To avoid that, paint floor to ceiling all the way across.
Long roller handles, scaffolding, etc. might be helpful.
If your walls are very smooth now, and you want to maintain a very smooth
surface, spray will be better. But - make sure you use a good airless
sprayer and do lots of drop-cloths. If there is a slight texture now, you
won't notice the difference with a properly applied roller job.
Dwight Duckstein, MCP
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