Cleaning Moss and Lichen Off Your Roof (Without Wrecking It) -- Plus a Plain-English Guide to Urethane
What's in this episode
Original Air Date: 8/1/2026 Episode Number: 470 Episode Summary Three topics this week. Dan opens with a paint science segment answering a listener question about urethane and enamel -- two words that appear constantly on paint labels and mean different things than most people assume. Then a full two-segment deep dive on moss and lichen: first, how to safely remove them from different types of siding, and then a step-by-step walkthrough of how Dan cleaned his own roof, what products he used, and what the warnings are. He closes with a quick listener question about painting over old glossy trim in a pre-1978 home. Timestamps [00:00] -- Show Intro and Promises [02:28] -- Paint Science: Urethane vs. Enamel [07:38] -- Choosing the Right Paint [09:56] -- Moss and Lichen Overview [10:35] -- Siding Segment Setup [11:06] -- What Moss and Lichen Are [12:43] -- Cleaning Brick and Masonry [15:09] -- Cleaning Wood Safely [16:56] -- Vinyl, Stucco, and Pressure Tips [18:27] -- Protecting Plants [19:22] -- Roof Segment Begins [20:02] -- Why Remove Roof Growth [20:14] -- Roof Damage Explained [21:52] -- Dan's Roof Wake-Up Call [23:48] -- Kill It, Don't Scrape It [24:12] -- Hire Out or DIY? [25:03]