Cleaning or removing mold/mildew from pine soffit boards, for re-staining.
We completed the exterior work on our house (NH, zone 6) in the fall of 2014, including the eastern white pine soffit boards. They were coated with Vermont Natural Coatings PolyWhey Exterior Penetrating Wood Stain. After not touching these boards for almost 8 years, the mold/mildew on them seems like a pretty natural occurrence (I’m confident this isn’t a building moisture issue). I’ve sanded a small section and it’s more than just superficial.
We’re going to be doing some exterior re-staining and touchup in the next couple months and would like to work on the soffit boards as well. Does anyone have a recommendation (preferably based on actual experience) for a wood safe product that could minimize or remove this mold/mildew growth? Ideally it would be a product that could be applied with minimal follow up (ex: not needing to rinse with massive amounts of water).
Keeping in mind that this work will be 20-35′ off the ground, it will be DIY, and we’d like to then re-stain the boards with a clear or semi-transparent product.
Thanks for any insight. I’ve attached photos and here is a link to high res versions: https://drive.google.com/drive/folders/1BA9dvwI8n-gGbkYri9sBd3TtoGphHt8_?usp=sharing
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Replies
I'd just power wash it with a solution of bleach, but being 20 feet off the ground, I might hire somebody to do it.
Mold Armor Instant Mildew Stain Remover and Spray Nine Mold and Mildew Stain Remover are popular options that get good ratings. These cleaning products often contain a mildewcide to kill mold and mildew spores, while also cleaning the surface. They may require less rinsing than dedicated stain removers.
In fact, I highly suggest hiring a professional cleaning service. They'll have the proper equipment and safety gear to handle the job safely and efficiently. You can search for power washing or exterior cleaning services on Aroundwire by following these steps:
1. Go to Aroundwire (https://aroundwire.com/)
2. In the search bar, type in "powerwashing near me" or "exterior cleaning services near me". The same scenario works for janitor jobs near me.