Fiberglass Deck Installation Guide

A Practical Guide to Building and Installing a Fiberglass Deck

Fiberglass deck is a composite decking product built from fiberglass reinforced plastic (FRP) and resin. Compared with conventional wood or metal decking, it offers a number of benefits, including high strength, durability, corrosion resistance, fire resistance, low maintenance, and environmental friendliness. That said, getting the full benefit from a fiberglass deck still depends on installing and caring for it correctly. The steps and tips below walk through how to build and install one.

Step 1: Get the Substructure Ready

The substructure forms the deck’s foundation and carries the fiberglass deck boards. Depending on site conditions and design preference, it can be built from wood, metal, or concrete. Whatever the material, it needs to be level, stable, and free of defects or damage, with enough ventilation and drainage built in to keep moisture from accumulating and causing rot. Design the substructure to match both the manufacturer’s specifications and the applicable local building codes.

Step 2: Cut and Drill the Deck Boards

The deck boards are the main component, giving the deck its surface and appearance, and come in a range of colors, textures, and sizes depending on the manufacturer and the customer’s preference. Cut and drill the boards to match the deck’s layout and design, using tools that are sharp and clean so the fiberglass doesn’t chip or crack. Smooth any cut edges with sandpaper or a file to guard against splinters or injury, and drill holes slightly larger than the fasteners so the boards can expand and contract with temperature changes.

Step 3: Fasten the Deck Boards in Place

Fasten the deck boards on top of the substructure with screws, nails, clips, or another fastener type recommended by the manufacturer, choosing stainless steel or another corrosion-resistant material so the fasteners don’t rust or stain the surface. Drive fasteners flush with the board surface without over-tightening, which can crack or warp them. Space the boards evenly, leaving a gap of about 3 mm to 6 mm between them for drainage and airflow, and stagger the joints for a pattern that looks better and holds together more securely.

Step 4: Add the Finishing Touches

A range of accessories and treatments can round out the deck’s look and function. Fascia or trim boards along the edges give it a cleaner finished appearance, while caulk or sealant in the gaps between boards keeps out water and stops weeds from coming through. A protective coat of paint, stain, or varnish adds color, gloss, or UV protection to the surface, and railings, lighting, planters, furniture, and similar extras can be added afterward to suit the customer’s taste and style.

Pre-Installation Checklist

Before starting installation, read through the following points carefully:

Inspect the delivered materials to confirm the shipment is complete and free of damage.

Keep the materials in a dry, shaded location until you’re ready to install them.

Handle the materials in protective gloves, goggles, a mask, and suitable clothing to avoid skin irritation or breathing in dust or fibers.

Use the right tools and equipment for cutting, drilling, and installation to prevent injury or damage to the material.

When designing the substructure and installing the deck boards, follow both the manufacturer’s guidelines and the local building codes.

Inspect the finished deck on a regular basis and maintain it per the manufacturer’s recommendations.