How long does expanding foam take to cure? (in very dry air)
Short answer
slower
Foam cures with moisture, so dry conditions slow it.
What changes the time
| Condition | Time | Why |
|---|---|---|
| for a thick bead | up to 24 hours | Thick foam cures slowly in the middle. |
| in very dry air | slower | Foam cures with moisture, so dry conditions slow it. |
Tips
- Lightly mist the gap with water first to speed curing.
FAQ
When can I trim expanding foam?
Usually after about an hour once it is firm.