Which should I install first if I have several flooring materials being installed in different parts of the house such as wood, carpet & travertine tile?
You should really install your natural stone flooring first which will be the travertine tiles before installing other flooring products that might be in contact with the travertine tiles. For instance, if you choose to go with filled honed travertine tiles size 18x18x 1⁄2″ the mud set base for installing this travertine tile needs to be at least 3⁄4″ thick to 1″ depends on how leveled your flooring is. Since it is straight edged, the existing flooring needs to be leveled using the mud set to avoid any lippage for that minimum grout lines. After the travertine tile is installed in your desired areas of the home, you can then start your wood or carpet installations to level them with your travertine tile flooring.