Kitchen & Bath: Tile Backers

Lightweight Board.

Made from extruded polystyrene, a closed-cell foam, this board is completely waterproof, front to back. For performance integrity, ProPannel tile backerboard should be installed using proprietary nails, washers, and mastic on all penetrations and seams. The Portland cementbased face coating is reinforced with fiberglass mesh and provides a base for thinset adhesive application. The manufacturer states that its board is suitable for use on shower walls as well as under floor tile, having passed the Robinson Floor Test for light commercial applications. The panel measures 3x5 feet x 1/2 inch, weighs 8.67 pounds, and cuts easily with a standard utility knife. The board lists for about $1.25 per square foot.

W.R. Bonsal, 800/738-1621, www.bonsal.com.

Thin Skin Backer.

On the theory that water is best controlled on the surface of the backerboard, whatever it may be, this waterproof fabric membrane installs directly over a drywall substrate, greatly simplifying wall preparation. Kerdi membrane is said to install as easily as wallpaper by embedding in thinset adhesive. Tile is bonded in thinset directly over the fabric. Used in conjunction with other proprietary components, the membrane is part of a complete ceramic tile shower enclosure system. The membrane lists for about $1.50 per square foot.

Schlüter Systems, 800/472-4588, www.schluter.com.

Cementitious Backer Unit.

If cement board's your thing, you've got plenty of company. When installed over a waterproof membrane, cementitious backer unit (CBU) provides an unbeatable tile base in high-moisture applications. PermaBase is composed of Portland cement, lightweight aggregates including expanded polystyrene beads, and fiberglass reinforcement facing. The manufacturer promises a cleaner, score-and-snap edge with little need for additional dressing. The panels may be nailed or screwed and are available in several panel sizes up to 4x8 feet and thicknesses from 1/4 inch to 1 inch. Prices vary by panel type.

National Gypsum, 800/628-4662, www.nationalgypsum.com.

Gyp-Board Backer.

With a core of water-resistance-treated gypsum, coated glass mats front and back, and a service facing of heat-cured acrylic, DensShield Tile Guard is claimed to cut and install with the same ease and equipment as regular wallboard. The gray acrylic face coating provides a built-in vapor barrier, although seams and penetrations must be sealed with silicone for contiguous integrity. Corrosion-resistant drywall screws install flush with its surface for interference-free tile installation. Wall panels are 1/2 inch or 5/8 inch thick by 4x8 feet with material cost around 60¢ per square foot; also available in 1/4-inch-thick 4x4 panels for floor and countertop applications.