Note: before starting it is worth noting that preparation is extremely important in ensuring the tiles are laid on a solid flat surface. It is advisable to lay floor tiles at the end of a job after all gas and water pipes and electrics are in place.
Start by removing the existing floor covering back to the floorboards. Repair or replace any loose or missing floor boards. Bang down any protruding nails. If any of the boards have curled along the edges you may find the electric sander useful for leveling these boards out.
Caution: there will be pipes underneath your floorboards especially in the kitchen. Make sure your screws are no longer than the thickness of the plywood and the floorboard combined. A rough guide would be 16mm floorboard + 12mm plywood = 28mm so a 25mm screw would be the safest option. If you are at all concerned, good practise would be to remove a couple of boards to see where the pipes run and mark on the boards with marker pen where you should avoid using screws.
Now it’s time to cover the whole floor with your plywood. For the first row start in a corner and lay the plywood in the opposite direction of the floorboards. If you are laying the floor in the kitchen at this stage you should have removed the plinth. How far you lay the plywood under your cupboards is up to you. Travertine is expensive so don’t waste what you cant see! Screw the plywood down spacing the screws roughly 20cm apart and avoid any pipe areas if you have marked them out. Stagger the next row to ensure a solid covering of plywood.
Note: to make the screws easier to start, first drill a small hole using a 2-3mm drill bit. You could also countersunk these holes but it isn’t essential.
In some old houses you may find the cooker area has a concrete base. It is advisable to drill into concrete here avoiding any gas pipes to secure the plywood. You will need a masonary drill bit and Rawl plugs for this.
Once your floor is covered in plywood you will need to seal this wood with a wash of a pva and water solution. This will stop the floor tile adhesive soaking into the wood.
Note: the pva wash should be done last thing before you go to bed as it will take a few hours to dry out.
At this stage you will need to plan how you are going to lay the tiles out. Travertine floor tiles are usually cut in a rectangular shape. I would recommend that you start at the internal door into the room with the tiles running long ways into the room. Start with a dry run, positioning the tiles across the doorway so you have a good spread spanning the doorway. Once you are happy you will now need to run a line from the edge of one of the tiles across the room. This will be your guide to help keep the tiles in a straight line. A great tool to help create long straight lines is a chalk line. Also draw a line across the opposite directoon of the room along the edge of the first tile. This will be your starting point.
Now that you are happy that your tiles plan is correct you can start to mix the adhesive. I would recommend using a White flexible adhesive. A dark adhesive is not recommend due to staining. Mix to the manufacturers instructions. Check the drying times of the adhesive as you may have limited time to use the mix before it becomes unusable. Only mix enough to use on small areas so as not waste any. You will need a spreader to apply the adhesive to the floor. From your starting point spread out enough adhesive to lay a couple of tiles. Spread the adhesive beyond the edges of the tile ensure the good adhesion. Line the first tile to the corner of your guide lines and gently press down on the tile. Use your spirit level to level out the tile in all directions. Wipe any excess adhesive from the surface of the tile with a damp cloth. Place your second tile next to this one and add your spacers between them. Level this tile. Once you have run out of adhesive mix some more and repeat the process. If you get to a point where a full tile won’t fit you will need to cut the tile using an electric tile cutter.
Once you have laid all the tiles leave them to dry to the adhesive manufacturers instructions. Once dry you can remove the spacers and give the tiles a good wipe down with a damp cloth. You are now ready to grout. I would recommend a sand coloured grout to blend in with the colour of the tiles.