generall, yes. What is the surface?

 

repainting a deck. Some bare smooth wood. Some paint. Mostly smooth maybe some rougher areas

 

If paneled wood, 3/8 will do the job. If timber 1/2" wool will be much better; back brush with the grain will help. Plan 2 finish coats.

Note: Over painting existing paint may cause the original to lift... maybe give a full day before between coats in the event there is additional paint removal.

 

if it were me, I would use a thicker nap roller, at least 1/2" maybe 3/4", and get a cheap 4" brush you can screw onto a pole. Roll a section, then lay it off with a brush. you dont have to put it on a pole, but it makes life easier. I usually do about a 4 board width at once, 3 if I have to get on my hands and knees to brush it out. I would roll about an 8 foot length by 4 boards, brush it out. if you're fast, go a little longer, if not, or if its hot out, go a little shorter, so you keep a wet edge. run the whole length, then come back and do it again.

brush marks look a lot better than roller stipple on decks, IMO, and you need a brush anyway, so why not do it all uniform?