Are thicker kiln shelves a better choice?

Kiln shelves are rated in terms of the maximum firing temperature which they can withstand, but of course the weight of ware placed upon them and the distribution of the load upon the shelf have a great bearing. If the shelf is to be packed with ware completely, and is being fired to stoneware temperature then it is always safer to use a thicker shelf to minimise ‘creep’ of the shelf. The ‘creep’ is the sagging of the shelf under load at temperature and will always happen to kiln shelves over prolonged firings.