Hi Dennis.

Thank you for your question.  The picture you described is from the article 'MDF for slatted bases', the MDF is 3 feet by 2 feet and is laid head to toe (top one) and side to side (bottom one).  This is just to prevent the central support bar from causing a ridge/dip in the centre of a mattress on a sprung slatted base.

The article 'Mattresses for Slats' shows how to completely cover your slats.  This we recommend for all foam based mattresses, just as the mattress contours to your body, it also moulds around the slats which will damage the mattress.  We also recommend this for pocket sprung mattresses where the space between the slats is greater than 3 inches (7.5 cm).  This is because the springs will settle into the gaps and cause a ridging in the mattress which in turn will damage the mattress, also you would not get the correct support.

To address the issue of the desirable flat surface for your mattress when used on a slatted base, you should really be taking measures to do all you can to achieve this. The best method we have found is to place thin sheets (about 3-5mm) of MDF onto your slats, to create the flat even surface required.

If we can be of further assistance please call the office on 0161 437 4419.  Our office hours are 8 am - 8 pm Monday to Friday and 10 am - 4 pm Saturday and Sunday.

Kind Regards

Michaela