OK to put latex satin over latex semi gloss?
 

Just wondering- the semi was done years ago. Guess I can lightly sand walls to help, eh? Hope I dont have to prime.....

Thanks

Noquacks, it depends. I usually scuff sand somewhat aggressively to give that Satin something to bite onto. Wipe off the dust and maybe test a small area to make sure of adhesion. If you see a separation of paint then you will have to prime with a bonding primer.

95% of the time, this will work just fine, you might have to do a little more than lightly sand though.

Satin over Semi-Gloss
 

As long as you are using a good quality paint you should be fine with a light sanding. In fact every wall that you paint a satin or above on should be lightly sanded anyway.