Classification of Sleeping Pads:
Inflatable Pad
Advantages: Comfortable and adjustable in softness, and not very expensive.
Disadvantages: Heavy, bulky, and prone to punctures. Air pads also do not provide great insulation.
Additionally, they require a good lung capacity — you have to inflate them by mouth.
Open-cell Foam Pad
Made from a spongy foam-like material.
Advantages: More comfortable than inflatable pads, lighter, cheaper, and better at insulation.
Disadvantages: Due to their open-cell structure, they offer poor moisture resistance and are not suitable for damp environments. They have worse insulation than closed-cell pads, are less compressible (harder to carry), and have a shorter lifespan.
Closed-cell Foam Pad
Made from foam containing numerous tiny sealed air cells.
Advantages: Cheap, excellent insulation, thin, and good moisture resistance.
Disadvantages: Heavier than they look; due to being thin, they are not very comfortable to sleep on.
Self-inflating Pad
Features open-cell foam sealed within a waterproof nylon shell that automatically expands when in use.
Advantages: As comfortable as open-cell pads but with much better insulation; waterproof and moisture-resistant; the air volume can be adjusted.
Disadvantages: Expensive; easily punctured; larger in size and heavier.
Aluminum Foil Sleeping Pad
Made of EVA foam, offering good moisture resistance and comfort.
Advantages: Lightweight, cheap, and good value for money.
Disadvantages: Prone to tearing.
Functions of Sleeping Pads:
First, protection against uneven ground. Since it’s hard to find flat ground when camping outdoors, sleeping can be quite uncomfortable, but using a sleeping pad greatly improves the situation.
Second, warmth. When camping outdoors, your body usually comes into direct contact with the ground (the insulation provided by the tent floor is minimal), so having a sleeping pad between your body and the ground significantly improves warmth.
Third, moisture protection. At night during outdoor camping, the ground is often damp, and since sleeping pads are waterproof, they help block moisture.
For sleeping pads, warmth, weight, comfort, durability, and size are all important in that order, but for a hiker, getting a good night’s sleep is crucial, and a good sleeping pad plays an important role.