Sleeping Pad Losing Air? Here's Why
Diagnose and fix air leaks in your sleeping pad. Find the most common causes and solutions to keep your pad inflated through the night.
A deflating pad halfway through the night is a miserable way to learn about air leaks. Sleeping pad air loss happens because of a few predictable reasons. Identifying which one is affecting yours narrows down the fix.
Most Likely: Valve Not Fully Sealed
Symptoms: Pad loses air steadily over several hours. You might hear a faint hiss near the valve. Pad is still firm when you first lay down but noticeably softer by morning.
Fix: Most valve failures come from user error, not defect. Pull the valve stem straight out, check that the internal seal is clean and dry, then reinsert it firmly. Twist counterclockwise until snug—don't force it, but make sure it's seated. Some valve designs (like Exped's) require a full quarter-turn past where you think they're closed.
Test by fully inflating the pad and listening closely near the valve for 10 seconds. If you hear air escaping, repeat the seating process. Most leaks stop here.
Also Common: Small Pinhole or Seam Leak
Symptoms: Pad loses air slowly but continuously. You can't see or feel a hole, but the leak doesn't stop. Deflation happens whether the valve is open or closed.
Fix: Fill a spray bottle with soapy water (dish soap and water works). Inflate the pad fully and spray the entire surface, focusing on seams and the bottom where damage from rocks goes unnoticed. Bubbles will form where air is escaping. Mark any holes with a permanent marker.
For pinholes under 2mm, a patch kit included with most pads covers it. Clean the area, let it dry completely, apply the adhesive patch, and weight it for 24 hours. For tears larger than 5mm or seam failures, the pad is likely unrepairable—replacement is more cost-effective than a professional repair.
Less Likely: Valve Cap or Pump Connection
Symptoms: Rapid loss of air right after inflating. The leak seems to be at the valve but the valve stem itself is sealed.
Fix: Check the valve cap—it should thread on smoothly without forcing. A loose cap allows air to escape around the threads. Some newer pads use one-way valves that prevent backflow, but the cap still needs to seal. Replace the cap if it's stripped or damaged.
If using a pump, make sure the connector is fully seated on the valve. Remove it, inspect both ends for cracks, and reconnect firmly. A poor connection at the pump interface will leak air during inflation but stop once you disconnect—this feels like pad failure when it's actually the pump.
Rare but Possible: Expansion Joint Failure
Symptoms: Pad deflates faster on cold nights. You might notice the leak only happens when the pad material is cold and stiff.
Fix: Temperature changes cause materials to expand and contract. If a seam is already stressed, cold can break the seal. This is a manufacturing defect. Contact the manufacturer for warranty replacement—this isn't something a field patch can reliably fix.
If Nothing Works
If you've sealed the valve, run the soapy water test multiple times, and the pad still loses air, the leak is either extremely small (in which case patching works) or a seam failure (in which case replacement is your option).
Before replacing, try this: Let the fully inflated pad sit for 24 hours in a quiet room. Listen near it periodically to pinpoint the leak location. A slow leak is still a leak, but it's fixable if you can find it. A fast leak that you can't locate usually means internal damage to a seam.