Hi Rob,

Thank you for your question.

The whole point of pocket springs in mattresses, is that they have a certain amount of body weight, on a certain tension of spring, so that your body makes an impression in the spring unit, meaning every time you move, those individual pocket springs move below you. To have a firm spring, the body weight needs to be 16.5st - 17st as a starting weight, to make an impression in that particular spring tension. If your wife at her current weight, went onto a firm spring, the springs are not actually going to move, and so the mattress really isn't doing its job. Obviously personal preference has to come into your mattress choice, but we need to make you aware of the above mattress science.

If you require any further assistance with regard to this issue or with regard to any of our products, please call the office on 0161 437 4419

King Regards Gary