Hi Craig,

Thanks for getting in touch with us about your bed question. Your question on mattress spring weights and tolerances is a really good one and is often misunderstood or misrepresented in mattress retailers!

Mattress springs as you have rightly pointed out are designed with weight tolerances in mind. This weight tolerance is the sleeper's bodyweight.

Have a look below to see the pocket spring tolerances for example:

These tolerances are for each sleeper. So if you have two very different weighted sleepers the answer lies with either a split tension mattress or a zip and link. This means that each side can have a different spring tension if need be.

Split tension Mattresses: These are a one piece mattress such as a kingsize but half will have one spring tension eg 1.2 soft and the other will have a different tension 1.4 medium.

They look and behave just like a regular mattress (see above) you can still turn and rotate them but you will need to follow your side of the mattress. You can only ever use adjacent spring tensions with a split tension mattress ie soft/medium or medium firm never soft /firm. This is because the jump between the two is too great causing a ridge or drop of in the middle. For that you would need a zip and link mattress.

Zip & Link Mattresses: These are two separate mattresses (in the same model) that have a recessed zip. They too allow you to have different pocket spring tensions.

However, in a zip and link mattress, you can have extremes such as a 1.2 soft and 1.9 extra firm if need be as there's a central perimeter between the two. You can also keep your side of the bed as they are rotated and turned over each month.

If you have any more questions please get back in touch with us on 0161 437 4419.

All the best John & Ryan