Although the different types of mattresses are quite different, they have to meet the same requirements.
The innerspring mattresses are made up of coil springs made of steel wire. This core can be constructed very differently. He has a relatively high elasticity and at the same time a good support force. The spring core must be optimally padded, because the springs must not be noticeable.
Good foam mattresses are built up in several layers. The middle layers have a higher volume weight and are therefore harder than the outer layers with a lower volume weight. Depending on the system, hollow profiles inside the mattress ensure ventilation. The foam core can only absorb a little moisture, so very absorbent padding is required.
This mattress – it is made of natural rubber – offers a soft, pliable elasticity, but it is usually too soft without central zone reinforcement. As with foam, a cushion is also required here to compensate for moisture.
With the waterbed, there is around 300 liters of water in a synthetic cover (with a mattress size 100 by 200 cm). In order to reduce the movement of water, the interior of the mattress is sealed off by several partition walls. Here, too, appropriate upholstery must ensure the right microclimate. The water adapts itself completely to the distribution of the load at all times, so the pressure is distributed absolutely evenly over the body and there can be no pressure points. However, the body is unable to adjust the volume of water available to its body temperature. For this reason, the water must be continuously tempered. Water beds must not be combined with base mattresses as they require a stable, level surface.