Painting - Latex over oil interior paint?

I did the alcohol test (based on some of the previous posts), my new house has walls of latex paint, and the trim and doors are oil based, they are in good condition, just a terrible color. :eek:

I would like to do the doors and trim in latex (easier clean-up, less odor).

Question:
Should I sand all the trim/doors (how much must be sanded- down to the wood, or just scratch it up)? Then can I use latex over the oil?

Or is there a latex primer I can use before I apply the latex top coat? And which would you recommend? All I can find is non-water clean up primers that say can go over oil.

Thanks,
DIYIdiot

Should I sand all the trim/doors (how much must be sanded- down to the wood, or just scratch it up)?
Just scuff them real good, you don't have to take it down to bare wood.
Then can I use latex over the oil? Or is there a latex primer I can use before I apply the latex top coat?
No, it needs to be primed with an oil primer. Latex just doesn't want to adhere to oil very well at all. Then you can topcoat it with a latex.

I appreciate the information.

This may be a stupid question (hence, my login name) but if I have to go to the trouble of using an oil based primer (which doesn't clean up with water) -- then why would a person prime with oil, then cover with latex?

I guess I'll just buy the oil-based paint, that way I only have to paint the doors/trim once, instead of twice.

Thanks!!! :)

The EPA has been pushing for laws for the past couple years now trying to rid the world of oil paints for environmental reasons. These new VOC laws have rendered many of the popular oils useless now. So the reason we prime with oil and then paint with latex is to change the painted area from an 'oil system' to a 'latex system'. This way, in the future, only latex will be required to paint that particular area. If its painted again with oil this time, oil will be required next time. Sooner or later, it needs to be changed to a latex system.