I went to Aldi this morning and bought few camping mats. It states it is 5cm self inflating mat.
However after opening the seals and letting it inflate for about an hour, it is about the same thickness as when I laid the mat. It is about 2.5cm thick after inflation. Where has the extra 2.5cm gone to? The pillow that came with it, inflates quite well and is about 8cm thick.
I might try opening another one and see how that one goes. I have very limited camping experience and these are the first self inflating mats that I have purchased.
Can anyone comment on their experiences and how the thickness is rated?
My experience has been you always end up blowing some air into self inflating mattress to get the most out of them.
You could exchange/refund the mattress but I bet no matter what brand you buy you will end up having to blow some additional air in.