A marble vanity top is a great addition to any bathroom design. Marble has a beauty and elegance unmatched by other materials, and enhances the look of any room. Using a marble slab vanity top in your bathroom allows you to undermount the bathroom sink, rather than hanging it from its rim. This clean look helps add to the beauty of the design. Attach the sink and faucet to the marble top before installing the top to the vanity for easier installation.

1
Flip the marble top upside down so that the unfinished side is face up. Install the sink to the base of the top by applying a bead of silicone adhesive around the opening of the sink cutout. Press the sink onto this adhesive and hold for a few moments to allow the adhesive to grab. Use epoxy to attach the sink's mounting hardware to the marble. Attach the bolt stems first by applying epoxy to the marble's underside and pressing the stems into place. Next, apply epoxy to the sink and attach the clamps. After ten minutes, tighten the clamp to the bolt with a wrench. Allow the epoxy to cure for 24 hours.

2
Attach the faucet to the vanity top. Take the top of each faucet off of its stem, push the stem through the holes on the vanity top and tighten the top of each faucet back on. Use the wrench to tighten everything down. The faucet will be hooked up to the water supplies after the top is fully installed.

3
Lift the vanity top onto the vanity to check fit and placement. Most vanity tops are made to fit the vanity and any walls. If this top was not made to fit the exact dimensions of the room, double-check fit and move the vanity or top as needed to accommodate walls or baseboards. Most vanity tops overhang the vanity by an inch on each side and the front. If the sink is fitting up against a wall, get the top as close as possible; if the wall is out of plumb, add a color-matched adhesive to fill this gap after installation, or install a backsplash to cover the gap.

4
Clean the top edge of the vanity where the marble will attach and make sure it is free of dust, debris and completely dry. Apply a bead of silicone caulk around the edge of the vanity. Press the sink on top of the caulk and double-check the fit. Move the vanity top into position, wiggling it slightly in the adhesive to get a good bond. Allow the adhesive to bond for 24 hours before hooking up drains and water supplies.