To paint or not to paint ?

That is the question.

We are in the process of a home remodeling project in San Francisco's Sunset District. A major part of the job was made necessary by dry rot damage to the front of the house that my current contractor said was caused by poorly installed waterproofing (paper and flashing). He has explained exactly what is necessary to achieve the maximum waterproofing, and I am confident in his ability to do that. We have chosen to replace the existing stucco finish with an integral color finish, and the question is whether we need to paint the stucco. Our contractor (and his stucco subcontractor) say no, because the waterproofing is really achieved by doing the paper and flashing, etc., correctly. Our architect, who is lawsuit-averse, wants the extra measure of waterproofing that paint would provide. Given the cost of painting the front of the house (several thousand dollars), this is not a trivial decision. Who is right? Thanks for your response.

Painting a natural cement stucco finish.

If you paint the stucco, you will lose the beauty of the natural color cement finish. Water will penetrate stucco even if it has been painted. I have proven this. The most important thing is that the flashing is done right, the windows are set right, and the roof is done right. Painting stucco can also be a maintainence trap. The paint will only last so long before it needs to be re-painted. The quality of paint has improved a lot over the last few years so if painting is the decision, newer masonry paints bond better and last longer than they did in the past.