Self Inflating Mats

Self inflating mats are in essence foam, wrapped in an air tight sleeve.  When you open the valves on the air tight sleeve, the compressed foam that wants to expand sucks air inside the sleeve. Once it's fully inflated, you then close the valve to stop the air escaping, and you lay on it!  

This design lets you conveniently collapse the foam for transport, then with the addition of the air, and the closed valve, the foam is provided with more structure to give you a comfortable nights sleep.  

There are self inflating mats available for all types of adventures including hiking - where weight and space are at a premium as well as mats for car camping of varying sizes, and thicknesses.

Not all mattresses are made the same.  

Different designs will involve bonding/glueing the outer sleeve of the self inflating mattress to the foam.  By doing this, this reduces the ability for air to transfer inside the mattress to where there is no weight - effectively leaving you laying on the ground.  

• Unbonded Self Inflating mats
  Cheaper mats, sometimes called 4WD Self Inflating mattresses are usually Non-Bonded/unbonded, and do suffer from air transferring away from where you're laying. Some brands when they make these mattresses, will then choose a foam that is denser so that you do not end up laying on the ground.  The trade off with this, is that your mattress is then heavier, and harder to roll.  It may not roll down as small as some bonded mats of the same thickness either.  Often when you lay on a unbonded self inflating mattress, you can identify this because your feet will lift higher into the air as you lay back - this is the air transferring away from your heavier upper torso.
• Bonded/Partially Bonded
  Bonded & Partially Bonded self inflating mattresses are where the best comfort is found, and the best performance is found.  A fully bonded mattress will have its entire exterior bonded to the foam inner.  In some cases, especially with many of the 3D self inflating mattresses, these are partially bonded.  They will usually be completely bonded on the top & bottom, but leave the side walls unbonded. This small amount of unbonded is generally not a problem for the performance of the mattress, and many prefer the comfort of the 3D mattresses - due to their thickness - usually at least 10cm, and in some models 15cm and even 20cm! 
• Adding Extra Air
  No matter which self inflating mat you choose, if you like it firm you may wish to add extra air to your mat to achieve the desired firmness that you like.  Some self inflating mats will have designed theirs to use the carry bag - this is common amongst BlackWolf and Tentworld Slumbermats amongst other brands.
• Coring
  During the manufacture of a self inflating mat, designers will consider coring the foam that is made.  This means to drill out/remove sections of the foam. This is done to achieve certain attributes - such as pack size, pack weight, ease of packaway.  In many high end self inflating mats, their coring will be extensive.  This means the mattress is lighter, but can mean that the insulation properties - measured with R values - is reduced.  A self inflating mattress thats extensively cored, will also be slower to inflate naturally.  Some of these mattresses can be so heavily cored, that you may need to assist it with inflating.
• Valves
  Different designs will incorporate different valves.  Some are basic valves where if you open it, the air can come in or out depending on whether there is weight on the foam or not.  Many nicer self inflating mattresses will come with optional one way valves.  These can be used to assist you with deflating your self inflating mat, stopping air coming back into the mattress whilst you're trying to roll it.

FINAL TIP!  We recommend that you do come into your local Tentworld if at all possible.  We have lots of models for you to lay on, so you can find the model that suits your sleep requirements best!