How to Guide

FAQs
Durable, Lightweight,
Waterproof Tile Backer Board
GoBoard
®
Basics
• What is GoBoard?
GoBoard is an ultra-lightweight yet durable, waterproof alternative to cement and other heavy tile backer boards and is manufactured by
Johns Manville, a Berkshire Hathaway company.
• Why do I have to use a tile backer board?
Tile backer boards provide a stable surface upon which to bond tile. GoBoard offers the advantages of being ultra-lightweight, easy to cut,
handle and install. And, best of all, it has waterproofing already built-in.
• What GoBoard sizes are available?
GoBoard is available in 3'x5' boards for 4" and 2" thicknesses and 4'x8' boards are available in 4", 2", s", 1", 12", and 2" thicknesses. 4" is
for floors and countertops while 2" and s" are for walls, showers, ceilings and floors. GoBoard ¼" and ½" are rated for use in residential
and light commercial applications. 2" and s" are available for use in transitions to higher profile adjacent floors and coverings. For floors,
we recommend using ¼" GoBoard for residential and light commercial applications. 1", 12", and 2" are for walls, benches, shelves, tub
surrounds, vanities, and countertops.
• How much does GoBoard weigh?
3'x 5' 4" GoBoard weighs 6.0 pounds and ½" weighs 7.5 pounds, up to 80% lighter than cement and other heavy boards. 4'x8' s" GoBoard
weighs 18.56 pounds.
• What materials are used to manufacture GoBoard? How can it be light and strong at the same time?
GoBoard’s exterior faces are comprised of proprietary coated fiber glass mats that provide excellent bonding and stiffness. The core is
made from high density polyisocyanurate (“polyiso”) closed-cell foam, providing strength, durability and waterproofness. Polyiso is a
frequently used building material for insulation, roofing and other applications — Johns Manville has been a trusted polyiso roofing products
manufacturer for decades.
• Will GoBoard break because it is so light? Is it strong enough for my tile installation?
GoBoard’s high density polyiso core leads to product compressive strengths of >250 psi (4"), >200 psi (2"), and >200 psi (s"), resulting in
Robinson Floor Test (ASTM C627) ratings of Light Commercial for both the 4" and 2" sizes.
• GoBoard is “waterproof” and other tile backer boards are “water resistant.” What is the difference?
GoBoard’s core is waterproof, passing ASTM D4068 testing. Water will not pass through the board like it will with cement boards, which
require separate waterproofing over the entire board. Seal only the board joints and fastener locations for a waterproof tile assembly.*
• GoBoard is more expensive. Why should I use it?
Despite having a higher purchase price than other heavy tile backer boards, GoBoard has a lower installed material cost because the installer
avoids much of the expense of waterproofing the entire board.* GoBoard saves time due to it being easy to transport, carry and maneuver
into fastening position. It can be cut right where it’s installed with a basic utility knife without crumbling or disintegrating. This also helps the
installer avoid the mess of cutting cement and other heavy boards.
Installation
• Can GoBoard be used in wet areas?
Yes! Because it is waterproof, GoBoard is an excellent tile backer board for wet areas.
• Can GoBoard be installed over concrete floors?
Yes, the concrete floor must be clean and fully cured, and surface imperfections must
be pre-filled with mortar prior to GoBoard installation. Laminate GoBoard to a concrete
floor by fully embedding it in mortar.