Temperature effect (pressure loss in cold water)
Also: pressure loss, topping up
If a packraft is inflated in warm air and then put into cold water, the air cools, contracts and the boat gets softer. Usually that's not a leak.
The Packrafting Store recommends topping up after about half an hour on the water, or briefly putting the boat in the water before starting and then topping up. Conversely, a firmly inflated boat in blazing sun on land can build up considerably more pressure. Don't leave it there for hours, or let some air out.
To check whether there's really a leak: inflate the boat fully, close the valves and leave it overnight in an evenly heated room. In the morning it should still be firm.
Sources and further reading
Research as of 13 Nov 2026. We have marked manufacturer information as such.