How long does joint compound take to dry? (in a humid room)
Short answer
longer
Humidity dramatically slows drying.
What changes the time
| Condition | Time | Why |
|---|---|---|
| in a humid room | longer | Humidity dramatically slows drying. |
| with a thick coat | up to 48 h | Thick mud dries from the surface inward. |
| with setting-type hot mud | 20-90 min | Chemical-set compounds harden far faster. |
Tips
- Thin coats dry faster and sand smoother.
FAQ
Why is my joint compound still wet?
Usually a thick coat or a humid room. Add airflow and wait.