The hardest part about installing the top is making sure that no tools scratch or crack the surface. It is important to be extremely gentle with the marble top during installation. Once the top is in place, the installation process is very easy and requires few specialized tools. It is important to ensure the marble top fits the vanity perfectly before gluing it to the wood surface.
Lay the marble countertop over the wood vanity to trial fit for shape. If the countertop is too large or too small, contact the manufacture to adjust the fit. If the fit is too large, you can try to cut it to the correct size yourself with a circular saw, but you risk splitting the marble. It is best to have a professional adjust the fit.
Make sure the top has the correct openings for any sinks, faucets or pipes that will run through it. If these are not placed correctly, contact the manufacturer and have it make the necessary adjustments.
Install any sinks, faucets or pipes into the marble top before gluing it to the wood vanity. Tighten any screws or attachments by hand. If you use tools, the marble can crack. Glue a sink in place with silicone caulk.
Apply a bead of sealing compound around all four edges of the vanity where the top will sit. Place the top over the vanity. Push the marble top flush against the wall.
Connect any pipe or drain fittings. Tighten all connections not directly attached to the marble top. Seal the joint between the pipes and the top with plumber's putty.
Apply a line of sealing compound between the edge of the marble top and the wall behind it. This prevents water from dripping down against the wall and ruining the countertop or wood. Allow all putties, sealing compounds and caulks to dry for 24 to 48 hours before using the vanity for any purpose, especially the sink or other water sources.