GoBoard®: Durable, Ultra-lightweight, Waterproof Tile Backer Board
A product by Johns Manville
Introduction
GoBoard® is an ultra-light, waterproof tile backer board engineered by Johns Manville for durability. It is up to 80% lighter than cement boards, easy to handle, and can be cut on-site with a utility knife without crumbling. GoBoard features built-in waterproofing.
Key benefits:
- ⏱️ Fast installation: Complete shower tile projects in half the time or less.
- ? Ultra-lightweight: Up to 80% lighter than cement boards, yet engineered for durability.
- ? Easy to cut, handle & install: Simply attach with GoBoard® Fasteners or GoBoard® Washers.
- ? Waterproof built-in: Seal only the board joints and fastener locations for a waterproof tile assembly per GoBoard installation instructions.
GoBoard is available in six thicknesses: 1/4" for floors and countertops; 1/2" and 5/8" for walls, showers, ceilings and floors; 1", 1 1/2" and 2" for walls, benches, shelves, tub surrounds, vanities and countertops.
Installation Instructions
1/4" GoBoard for Floors & Countertops
Wood Floors
Framing, Control Joints and Subfloor Requirements
Framing: All framing must comply with local building code requirements and be designed for a maximum allowable assembly deflection of L/360 (L/720 for stone) under intended live loads.
Control Joints: Consult TCNA Handbook installation Method EJ171. Location, width, and details should follow sound architectural practices, specified by an architect, builder, or design professional.
Subfloor: Joist spacing should not exceed 24" on-center. Use exterior grade 5/8" plywood or 3/4" OSB, securely glued and fastened to joists.
Installation
Measure GoBoard, then score and snap. To score, cut through the outer facing with a utility knife along the measured line. To snap, firmly grab the board edge and apply downward pressure at the scored line. Alternatively, stand the board on edge and place your knee against the back of the board directly behind the scored line, bending it backward.
Stagger all board joints, ensuring they do not line up with subfloor joints, and leave a 1/8" space between all corners and edges.
Apply mortar (as specified in Approved Materials) to the subfloor using a 1/4" square notched trowel. Laminate pre-cut GoBoard to the subfloor by firmly pressing it into the mortar, ensuring full embedment.
Fasten GoBoard to the subfloor with GoBoard® Fasteners (max spacing 8", within 1/2" - 1" of perimeter edges) or alternative fasteners (max spacing 6"). GoBoard Washers can be used as an alternative (max spacing 12") following instructions at www.jm.com/goboard.
Fill all joint gaps with mortar. Embed 2" alkali resistant fiber glass mesh tape in the mortar, ensuring full coverage.
For waterproof installations, seal all joints and fastener locations with two coats of liquid waterproofing membrane, extending at least 1" beyond mortar.
Concrete Floors
Installation
Ensure the concrete floor is clean, fully cured, and surface imperfections are pre-filled with mortar. Follow wood floor installation instructions, but skip the fastening step and ensure GoBoard is fully embedded in the mortar.
Countertops
Installation
Securely fasten 3/4" exterior grade plywood to the cabinet, ensuring maximum surface variation is no more than 1/8" in 10'.
Measure, score, and snap GoBoard as described for wood floors.
Apply mortar to the plywood base using a 1/4" square notched trowel. Fully embed GoBoard by firmly pressing it into the mortar.
Fasten GoBoard to the plywood with GoBoard® Fasteners (max spacing 8", within 1/2" - 1" of perimeter edges) or alternative fasteners (max spacing 6"). GoBoard Washers can be used as an alternative (max spacing 12") following instructions at www.jm.com/goboard.
Fill all joint gaps with mortar and embed 2" alkali resistant fiber glass mesh tape. Seal all joints and fastener locations with two coats of liquid waterproofing membrane, extending at least 1" beyond mortar.
1/2" and 5/8" GoBoard for Walls, Showers, Ceilings & Floors
Walls
Framing Requirements
All framing must comply with local building code requirements. Framing members shall be spaced a maximum of 16" on-center and be a minimum of 2"x 4" nominal (wood) or No. 20 gauge (metal). Studs shall be furred out flush with receptors and GoBoard edges should be continuously supported.
Installation
Measure and cut GoBoard using the score-and-snap method. Apply a continuous bead of GoBoard® Sealant or approved sealant to the bottom edge of GoBoard. Ensure a 1/8" gap between GoBoard and the base, completely filled with sealant extending at least 1" onto the GoBoard surface. Fasten GoBoard to studs with GoBoard® Fasteners (max spacing 8", within 1/2" - 1" of perimeter edges) or alternative fasteners (max spacing 6"). GoBoard Washers can be used as an alternative (max spacing 12") following instructions at www.jm.com/goboard.
Apply sealant to the top edge of GoBoard, ensuring a tight seal and a 1/8" gap. Fasten as above and spread excess sealant to at least 1" beyond the joint.
Seal all fastener locations and joints (between boards, corners, and changes of plane) with GoBoard Sealant or approved sealant. Ensure each fastener location is covered with at least a 2 1/2" diameter patch. All joints should be completely filled with sealant and spread 1" beyond the joint.
Joint Sealing Alternative: Leave a maximum 1/8" gap between boards, fill with mortar, and embed 2" alkali resistant fiber glass mesh tape. For waterproof installations, apply two coats of liquid waterproofing membrane extending at least 1" beyond mortar.
Steam Showers
Follow wall and ceiling installation instructions. Install a manufacturer-approved vapor barrier directly to wall studs and ceiling framing behind GoBoard, or over the external surface of GoBoard, per manufacturer's instructions.
Ceilings
Framing Requirements
All framing must comply with local building code requirements and support total system dead load with deflection not to exceed L/360 of the span. Framing members shall be spaced a maximum of 16" on-center, and GoBoard edges should be continuously supported.
Installation
Start on one edge, orienting GoBoard length-wise with wall installation. Use the "score and snap" method. Fasten GoBoard to ceiling studs with GoBoard® Fasteners (max spacing 8", within 1/2" - 1" of perimeter edges) or alternative fasteners (max spacing 6"). GoBoard Washers can be used as an alternative (max spacing 12") following instructions at www.jm.com/goboard.
Ensure all GoBoard joints, change of plane joints, and fastener locations are sealed.
Floors
Follow 1/4" GoBoard wood floor or concrete floor installation instructions.
Approved Materials
- Fastening: Wood: GoBoard® Fasteners (11/4" long), GoBoard® Washers, backer board screws (11/4" long), galvanized roofing nails (11/2" long) or 16 gauge galvanized staples (1" x 1"). Steel Framing: GoBoard® Fasteners (11/4" long), GoBoard® Washers, or backer board screws (11/4" long).
- Bonding: Dry set mortar compliant with ANSI A118.1 standard or Polymer modified thin-set mortar compliant with ANSI A118.4 standard.
- Joint Sealing: GoBoard® Sealant (see www.jm.com/goboard for approved alternatives) or 2" wide polymer-coated alkali-resistant fiber glass mesh tape and mortar, coated with a liquid waterproofing membrane for waterproof installations.
- Grout: Cement grout compliant with ANSI A118.6 standard, high performance cement grout compliant with ANSI A118.7 standard, or epoxy grout compliant with ANSI A118.8 standard.
- Tools: Utility knife, pencil/pen, straight edge, measuring tape, putty knife, roofing nail or backer board screw fastening device, 1/4" square notched trowel, caulk gun, 1"-3" paint brush (for liquid sealant).
Limitations
- GoBoard must not be used as a structural load bearing member. Follow all local and national building codes.
- In flooring applications, GoBoard is for Residential and Light Commercial use only and should not be used as a shower pan base.
- Do not use drywall nails, tape, or joint compound. Fully embed GoBoard into mortar prior to fastening for floor applications.
- Where waterproof installations are required, ensure all joints and fastener locations are sealed with GoBoard Sealant or an approved sealant. All joints must have at least a 1/8" gap completely filled with sealant extending at least 1" beyond the joints.
- For steam showers, install a manufacturer-approved vapor barrier directly to wall studs and ceiling framing behind GoBoard, or over the external surface of GoBoard, per manufacturer's instructions.
- For floor installations, tiles must be a minimum of 6" in size (individual tile dimensions).
Technical Data
| Property | Method | GoBoard® (1/4") | GoBoard® (1/2") | GoBoard® (5/8") | GoBoard® (1", 1 1/2", 2") |
|---|---|---|---|---|---|
| Dimensions (feet) | ASTM C473 | 3'x5', 4'x8' | 3'x5', 4'x8' | 4'x8' | 4'x8' |
| Thickness (inches) | ASTM C473 | 0.26 | 0.47 | 0.60 | 1.0, 1.5, 2.0 |
| Board Weight (lbs/ft²) | 0.40 | 0.50 | 0.58 | 0.62, 0.81, 1.0 | |
| R-Value (°F·ft²·h/BTU) | ASTM C518 | 1.2 | 2.3 | 2.9 | 5, 7.5, 10 |
| Compressive Strength (avg. psi) | ASTM D2394 | 250 | 200 | 200 | 125 |
| Moisture Movement (%) | ASTM D1037 | <0.07 | <0.07 | <0.07 | <0.07 |
| Surface Burning Characteristics¹ | ASTM E84 | Pass | Pass | Pass | Pass |
| Waterproof² | ASTM D4068 | Pass² | Pass² | Pass² | Pass² |
| WVT Permeance (perms) | ASTM E96 | <1 | <1 | <1 | <1 |
| Resistance to Fungi / Bacteria | ASTM G21/G22 | No Growth | No Growth | No Growth | No Growth |
| Freeze Thaw | ASTM C666 | >25 | >25 | >25 | >25 |
| Robinson Floor Test | ASTM C627 | Light Commercial | Light Commercial | — | — |
¹ Per International Building Code Requirements
² ANSI A118.10 certified
GoBoard is waterproof. GoBoard core is not made from polystyrene and will not melt and flow.
Safety & Handling
Safety: Wear gloves, safety glasses, and long sleeve shirts/pants. Follow good safety practices. Temporary mechanical abrasion (itching) of skin, eyes, and respiratory tract may occur upon exposure to fibers or dust. GoBoard contains no cement.
Storage and Handling: Deliveries should be in unopened packages. Store flat and in an enclosed shelter.
Limited Warranty
Johns Manville ("Seller") warrants GoBoard products for one year from the date of purchase against defects in material and workmanship, manufactured to Seller's product specifications.
Seller disclaims all other warranties, express or implied, including implied warranties of MERCHANTABILITY and FITNESS FOR A PARTICULAR PURPOSE.
Claims must be submitted in writing within 10 days of visible damage/defect discovery, or within 30 days of defect discovery, but no later than 1 year after product purchase.
Limitation of Remedy: Seller's liability is limited to repair, replacement, or refund of the purchase price at Seller's option.
No Recovery of Consequential or Special Damages: Seller is not liable for any consequential, special, incidental, indirect, or punitive damages, including property damage claims.
Some states may not allow these limitations.
Installation Guide
For detailed instructions, visit: www.jm.com/goboard
