Materials for slate bathroom floor in old traditional stone house?

[Rhedyn]

Hello all, I'm looking to lay a Penrhyn slate floor, approx 1.5m x 1.8m, for a first floor bathroom in a very old (but not listed) traditional Welsh stone farmhouse, and I have some questions about the best approach to take. I have attached a photo of the underside of the wood beam and plank floor, taken from the hall and loo directly below, to show what the base flooring is made of and how it is constructed. Bathroom will not include a shower, only a bathtub.

1) Should I follow the advice given in the supplier's guide or is there a more "traditional materials" approach better suited to a property like mine?

2) If following the supplier's guide, should I use marine plywood or cement backerboard? Should I also put in some sort of membrane? Will I need to apply acrylic bonding agent onto the plywood or backerboard? What would be a good choice of adhesive?

Thanks very much for any advice.

 

[gamer1]

It's a good idea to consult the supplier's guide as a starting point. However, given the traditional nature of your farmhouse, you might want to blend modern materials with a touch of tradition. Penrhyn slate is a beautiful choice, and you can enhance its appeal by opting for a traditional installation method, such as dry-laying the slate on a bed of mortar.

For the subfloor, marine plywood is a solid choice due to its water-resistant properties, but cement backerboard is also suitable. Adding a waterproof membrane is advisable, especially in a bathroom. Using an acrylic bonding agent can help improve adhesion. As for adhesive, go for a high-quality, flexible thin-set mortar suitable for natural stone tiles