mildew

[jlennon1915]

My home was originally trimmed in enamel paint when built 20 years ago. Every year we had a bad case of mildew growing on the house. I would clean the mildew with a solution of clorox and jomax and we would repaint with enamel every 4-5 years. 2 years ago a painter convinced us he could treat the enamel paint with a chemical, which would allow us to paint over the enamel with latex which is much better in resisting mildew. It worked for a year then the mildew returned and is very difficult to clean. We now have latex painted over enamel with a severe case of mildew. What can we do?

[Cal]

Thanks for asking jlennon1915, and Welcome to the Painting Forum. Not knowing exactly what was used Alkyd or Acrylic enamel, would probably suggest a scuff sand on all painted trim surfaces. This may seem a very large task, but several power tools are now available. One that comes to mind is the Wagner Paint Eater. Has a plastic type disc that scuffs paint like nobodies business, but will not harm the wood. After scuff sanding, would suggest a Acrylic XIM bonding primer on all bare wood surfaces. Allowing to dry overnight before applying finish coats. Going all out with paint quality, would recommend a high quality exterior paint such as Super Paint by Sherwin Williams. Both primer and paint has ammonia and formaldehyde built into paint formulas which keep down the mold and mildew. Hope this helps.
Welcome again to the PF.
Is this in typically a shady area? Stays wet and damp most of the time?

[jlennon1915]

Thanks for info. I don't know what type of enamel was used originally. My house is large with a lot of trim in very difficult places to reach. It will be very labor intensive to sand all of the trim, although I understand this may be the only answer. I live in NC with high humidity in the warm months.

(10-30-2010 07:21 PM)Cal Wrote:  Thanks for asking jlennon1915, and Welcome to the Painting Forum. Not knowing exactly what was used Alkyd or Acrylic enamel, would probably suggest a scuff sand on all painted trim surfaces. This may seem a very large task, but several power tools are now available. One that comes to mind is the Wagner Paint Eater. Has a plastic type disc that scuffs paint like nobodies business, but will not harm the wood. After scuff sanding, would suggest a Acrylic XIM bonding primer on all bare wood surfaces. Allowing to dry overnight before applying finish coats. Going all out with paint quality, would recommend a high quality exterior paint such as Super Paint by Sherwin Williams. Both primer and paint has ammonia and formaldehyde built into paint formulas which keep down the mold and mildew. Hope this helps.
Welcome again to the PF.
Is this in typically a shady area? Stays wet and damp most of the time?

[Cal]

Checking on a better solution than bleach for you. Will get back asap. to a paint quote, having a 10:00 appoint.