Priming for Latex Paint

[Bill Clifton]

Help - I removed a wall and had some sheetrock work done to finish the cut out area. I ended up with about 12" - 18" wide strip of new sheetrock. I primed this area and painted it with a Sherwin Williams interior latex with a satin finish. I got a perfect match to the existing with the color but the sheen wasn't correct. SW has 40% off this weekend so I went and got the same color in a flat sheen which will match the existing.

I jokingly said, well I won't have to prime and the clerk corrected me - she said that when going from a higher sheen latex to a lower sheen latex you must prime first. I have never heard of priming between coats of latex even if the sheens are different.

Help - do I need to prime?

[Brian Tymchak]

I rolled an egg shell (SW) over top an unknown brand semi-gloss last year with no primer. Worked just fine.

[Jason Roehl]

Ignore the clerk. There's high turnover and not a lot of training in those positions. Managers tend to be more knowledgeable, but even then, they aren't tech support, and generally haven't been career painting contractors.

There's rarely a good reason to prime before doing interior painting, and this is a case where it's definitely overkill.

[Rich Engelhardt]

when going from a higher sheen latex to a lower sheen latex you must prime first

Possibly - - a glossy finish should be either primed with something like Glidden Gripper or scuff sanded to provide some "tooth" for the finish coat to adhere to.

However - - having said that....
The 100% acrylic formulations in use today have an amazing amount of "holding power" compared to the products available 15 years ago or more.

Personally, I'd just scuff sand the old finish using 220 grit paper or a sanding sponge just to play it safe.

[Myk Rian]

I rolled an egg shell (SW) over top an unknown brand semi-gloss last year with no primer. Worked just fine.

We did the same in 3 rooms. No problems.

[Rich Riddle]

I do prime when going from a higher sheen to a lower sheen but that's old school to say the least. Probably a throw-back to the days when paints had very different inherent qualities. I use original Kilz when priming.

[Neil Gaskin]

The clerk is wrong, while it may be a "best practice", like the others have said, it is wholisticaly unnecessary. It would help to lightly hit the wall with a screen before painting, but even if you paint directly over the existing, it will be fine.