mildew on floor joists & bottom-side of subflooring
The first question I have is: How sure are you that the mold/mildew has 'stopped' forming? In other words, if it's STILL 'growing', then it's getting fed.
What I mean by fed is that mold/mildew thrive under certain conditions. Relatively high humidity, relatively warm temperatures, and relatively 'stable air' will keep the garden growing. If you dramatically reduce, or better yet eliminate, one or more of these conditions, your problem may go away. However, until you're sure that your problem isn't being fed, my suggestion may only work for a limited time.
So, assuming this is a 1-time 'fix', mix a solution that's relative to 1 cup of Bleach to 1 gallon of Water. (If you're using a pint of water, use 1/8 cup of bleach.) You can certainly go heavier than what I'm recommending based on how bad your problem is but, in short, pure Bleach isn't necessary (nor is anything near that saturation.)
Spray the mixture on the area and wait 5-15 minutes. Spray it until it drips a little (so be sure you cover the floor w/newspaper, or something.) Then, spray it a 2nd time and wait again. THEN, wipe it off w/a rag. Rinse the rag regularly and thoroughly, making sure the water (if it's in a bucket) is kept clean.
If, after a few weeks you see the problem return, then you'll know that the problem wasn't a 1-time problem. This is where you need to look at what's feeding the problem and decide which 'variable(s)' you're gonna change to 'fix' it on a more permanent basis.
My best to ya and hope this helps.
Jay J -Moderator
- 15 Old House Features We Were Wrong to Abandon
- 17 Tiny Bathrooms We Love
- 20 Insanely Easy 60-Minute Home Improvements
- 70 Gardening Tricks and Ideas for Total Beginners
- 16 Inventive Beds You Can Make Yourself
- 142 Remarkable Houses Around the World
- 11 Clever Alternatives to Kitchen Cabinets
- 7 Easy Budget-Friendly Backyard Makeovers
- 159 Smart Storage Ideas for the Whole House
- 10 Room Dividers to Bring Order to Your Space
- Shelf Life: 10 Bookcase Projects You Can DIY
- 11 Creative Garden Borders You Can Make—Easily!
- Tips and Tricks to Fit More into Less Closet Space
- 11 Amazing Homemade Sheds to Inspire Your Own
- Pest, Be Gone! 10 Steps to a Critter-Free Home
- 17 Design Inspirations for Mudrooms and Entryways
- Recipe for Success: 10 Easy Kitchen Storage Hacks
- Laundry Room Ideas to Knock Your Socks Off
- Winning Combinations: 9 "Can't Miss" Color Schemes
- Secret Rooms: 10 Special Spaces Hidden from Sight