Addressing rust spots on a stucco home


I own a home in San Francisco whose stucco is showing random rust spots. At first I thought that the stucco was not thick enough and/or the lath or fasteners were not of the proper type but now I am more inclined to believe that iron specs contaminated the sand used at the stucco material (there was a class law suit against a local sand supplier a few years ago because of this type of contamination, I was told).

I want to repaint the house and would like to make sure that I take all the right steps to make sure that the rust spots do not come back after the paint job.

I am considering using F-9 Barc and/or Rusterizer to attack the stains at first and then using two coats of a good quality primer followed by two coats of an elastomeric paint.

Has anyone at this forum faced a similar situation and what solution did you find? I would appreciate any opinion on my approach as well.

One Response

  1. To address rust spots on stucco before painting, you must follow a systematic process to ensure a successful outcome. Here’s a step-by-step guide:

    1. **Clean the Surface**: Remove loose rust, dirt, and debris using a wire brush, sandpaper, or a pressure washer. Make sure the surface is clean and free from any contaminants.

    2. **Use a Rust Converter**: Apply a rust converter solution to the affected areas. This will chemically convert the rust into a stable compound, preventing further corrosion. Only needed if the rusty areas is particularly pronounced.

    3. **Repair and Patch**: If there are any holes or deep rust spots, fill them with an appropriate patching material like stucco patch or epoxy filler. Smooth out the surface to ensure an even finish.

    4. **Priming**: Apply a rust-inhibiting primer to the repaired areas. This will provide a protective barrier against future rust formation and promote adhesion for the paint. Spot priming is fine for small rusty spots.

    5. Seal all gaps around windows, doors, the soffits to the stucco, etc. Keep water out so no more rusting spots in the future.

    6. **Painting**: Once the primer is dry, you can proceed with painting the stucco surface. Choose a high-quality acrylic stucco paint that is suitable for exterior surfaces and offers good adhesion and durability. An elastomeric coating is best but a regular house paint will do the job nicely.

Leave a Reply

Your email address will not be published. Required fields are marked *

House painting Search


Trending posts

No posts found


Don’t miss our future updates! Get Subscribed Today!