Cleaning Cement prior to painting

[06Honda]

I am painting a 8 x 8 x slab using Stoneffects Rollable paint with primer in it already. I own a power washer and was wondering if that alone is good enough to wash the slab and let dry before painting. There is a entrance roof over it so its not totally exposed. See image for surface I am doing. My plan is to also apply a clear sealer at the end of the job to extend the life span of the product. Thanks for any tips.

[HayZee518]

slab

Any concrete that is wet and appears to be dry really isn't. Concrete is a mixture of aggregate [stone] sand [silica] and portland cement [ baked ground rock] and limestone.
Hence it is porous.
Pressure washing will remove some of the surfactants in the form of a whitish powder.
To be absolutely clean it should be acid scrubbed.
I can't see how a primer can be in an all-in-one application.
A primer "primes" the surface for a finish coat.

[pushkins]

I know the product your referring to Honda, it's a paint product and as a paint product it works pretty well. Power washing is a must a light solution of hydrochloric acid wash would be advisable as well. You will have to wait up to a week between washing and applying the paint to ensure the concrete is dry enough for adhesion of the paint.

IMO stains are a much better option, they permeate into the concrete and don't have anywhere near as much "wear" paths and you can clear coat over a stain (clear coat doesn't work so well over paint).