Intro:
If your crawlspace looks like a set from a scary movie, don’t panic. You don’t need a $15,000 fix to make it livable—you just need a plan. Here’s how to clean it up without losing your mind (or your budget).
Step 1: Clear Out the Junk
Remove wet insulation, debris, trash, and anything that doesn’t belong (yes, even that forgotten paint can from 1998).
Anything organic like wood scraps or cardboard? Gone. These are mold’s favorite snacks.
Step 2: Lay Down a Vapor Barrier
Even a cheap 6-mil liner is better than bare dirt. Cover the ground to keep soil moisture from rising.
Pro Tip: Tape seams if you can. If not, overlap generously.
Step 3: Monitor Conditions
Install a humidistat or a basic weather station in the crawlspace so you can track humidity from upstairs.
Target:
✅ Relative humidity under 60%
✅ Wood moisture content between 12–16%
Step 4: Seal the Obvious Leaks
Check the crawlspace door—it’s often the biggest air leak. Add weatherstripping or insulation board if needed.
Seal vents if you’re going for a closed system.
Step 5: Address Air & Duct Issues
Leaky ductwork? Fix it. Every degree drop in air temperature adds 2.2% to relative humidity.
Check for condensation inside duct insulation. If it’s soaked, dry it and re-tape.
Step 6: Install a Dehumidifier (If Needed)
If your humidity stays above 60%, it’s time for a dehumidifier. Even without full encapsulation, this will make a huge difference.
When Cleanup Isn’t Enough
If the space is huge, broken into multiple rooms, or moisture won’t quit, you may need to think bigger—like finishing the encapsulation process. But for most people, these steps work wonders.
Bottom Line:
A crawlspace doesn’t have to be perfect—it just needs to be dry and clean enough to keep your home healthy. Start small. Do what you can. And remember, good enough is better than ignored.
👉 Up next: What Is the Clay Bowl Effect?
👉 Or start from the top: Crawlspace Knowledge Hub
