How to install slate flooring on wood floor?

If you want to install a slate subfloor on wood flooring, it (the wooden floor) should be, at least, 1 -1/4 inches thick. If not so, apply 1/2 inch thick plywood over a standard 3/4 inch thick subfloor material. Screw the 1/2 inch thick plywood to the existing subfloor spacing the screws every 8 inches on center. Apply a thin coat of water-based urethane to the final layer of plywood that will prevent swelling by stopping water from soaking into unprotected plywood. Installing one-half inch thick cement board on top of the regular 3/4 inch subfloor is a better choice if that option still remains.

Other option is to use a crack isolation fabric in between the slate and the wood flooring. These fabrics work well to offset any differential movement between the wood subfloor and the slate. Wood may expand and contract with changes in humidity. However, slate will not react to these weather changes. The fabric absorbs the differential movement between the materials.

For step by step instructions on slate flooring installation in general, refer to Installing Slate Flooring Tiles- A Guide

Source: Ask the Builder

Tips on Laying Slate Floor Tiles

• Slate tiles are packed tightly that might result into some broken tile pieces. You would not be able to make out this when you buy your slate floor tiles. So buy an extra box of slate floor tiles of your choice.
• Slate tiles can often be a little muddy too. So rinse them off before laying your slate floor.
• its better to cut slate with a right angle grinder or tile cutter (keep both of them handy)
• When cutting slate tiles, use a lots of water. Slate produces a large amount of dust if cut dry.
• Use stone sealer on slate- the side that will face up- at least once before you lay the flooring. This will avoid the mess when you grout the slate tile floor.
• Lay a very thick layer of thin-set because of the varying thickness of natural slate. Keep an extra day in hand or increase the time allowed to set thick layers of thin set.

Before buying slate floor tiles, know the characteristics and types of Slate Floor Tiles