I am remodeling a house in have a project in Santa Fe, NM that has painted stucco. The stucco is the traditional multi coat and the paint is not breathable and causing the stucco to crack. This is the first part of the problem. The second part is that this project consisted of both installing new windows and moving existing windows. Now in the locations of the existing windows (that I moved) I have applied the stucco and need to apply the color coat this summer. My concern is that since the previous owner of this property painted the stucco the color coat that I am going to apply will not adhere to the cementious material in the stucco due to the physical barrier of the paint. The only this method that I can think of to remove the paint from the existing structure would be to lightly sand blast and manually scrape it off with a wire brush. Any suggestions before I sandblast the house?
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
Fine Homebuilding's editorial director has some fun news to share.
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
Be prepared to replace it out of your pocket.
Don't you dare sandblast it!
I had a very similar set of issues on a project in Albuquerque. You have two options:
One is to apply a bonder which is essentially a glue to bond the new stucco to the old paint. The second and best option given the cracking you have, is to re-lath and re-stucco the entire house. Re-lathing is really the only effective way to keep the old cracks from telegraphing. But then again, you may get new cracks.
Also, your cracks are likely due to other causes, namely lack of or poor use of expansion joints, problems with the original stucco or its application and curing, or settling. If you're dealing with a flat roof then re-lathing and stuccoing should be done at the same time as a new roof. This will give you two chances to rewrap the parapets which are the source of so many problems; once when the new roof goes up and over and then again with the new stucco.
Lance
Thank you for your info. As much as I hate to re-lath and re-stucco the entire house, I believe that it is the way to go. how would you suggest removing the paint so that the scratch coat will adhere? The way that I see it is that I would have to rough up the surface to the existing stucco to remove the paint, then apply my new scratch coat and the final color coat. A large concern of mine is if I stucco over the coat of paint then I will really reduce the breathability and thereby promoting future cracking.
By re-lathing I mean new metal- stucco wire over fields and expanded metal lath at corners, windows, etc.- then the new stucco is independent of the original. Do not fixate on "breathability;" the important thing is good stucco well applied and wet cured in the appropriate weather. Once cured, if moisture is kept from invading the stucco from say leaks at the parapets, it is no problem to paint, atleast in my experience. That said, if you do decide to go the full route of all new exterior I'd get some estimates as this is best done in whole house coats done all at once by experienced crews. You may find that the cost is more affordable than you might think. Another possibility is to wrap the house in foam before lathing, adding lots of R-value to the wall assembly.
Lance