Hi, I’ve bought the below tiles from B&Q to go onto a small fireplace hearth in a bedroom (purely decorative - no actual fire will be lit!) I’ve made a timber frame hearth that I was planning to cover in left over mdf, then tile on top. I’ve got confused reading various blogs! Can I tile onto the left over mdf? If not, what can I use as an alternative (I’ve also got left over furniture ply, like the stuff that backs the kitchen cabinets - will this work?) The tiles are ‘natural stone’, what adhesive should I use? does it matter what grout I use? https://www.diy.com/departments/dir...le-sheet-l-300mm-w-300mm/5059340194592_BQ.prd Thank you!