How to Install Fiberglass Paneling

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Fiberglass paneling is often used as a protective roof cover over decking or on carports. Although generally corrugated, it can be bought in flat panels and is available in a number of colors. Fiberglass paneling is often treated to prevent UV light from coming through. This is especially good on the decking as it allows people to sit outside in comfort without the risk of sunburn and skin cancer. Installing fiberglass panels isn’t especially difficult and doesn’t require special tools.

Position the Paneling

When installing fiberglass paneling as a roofing structure over decking, correctly positioning it on the frame you’ve made is vitally important. Place the first panel so it extends over the side of the frame by 6 inches with one end tight against the house and the other end extending over the end of the framework.

Screwing the First Panel

Starting at the side frame of your deck, hold the fiberglass panel in place and drill a hole through the panel and into the wood approximately 2 inches from the house. Butt a rubber washer over a 3-inch wood screw and tighten it into the hole. The rubber washer will prevent water from entering the wood through the screw hole, keeping your roof watertight.

Keeping the panel straight, add more screws at 1-foot intervals for the length of the wood frame. Now, screw down the panel in the same manner on the front of the frame so it’s held securely.

Repeat this on all the studs covered by the panel, except for the final one it will cover. You should only screw through on the bottom part of the corrugation where it touches the wood.

Adding More Panels

It will take several fiberglass panels to cover the roof of your deck. To add each one, you need to overlap the panels by at least 8 inches. Screw down the second panel in the same way you attached it to the first. Your first holes should go through both panels where they overlap, into the wood.

To stop water from leaking through the area where the panels overlap, you should run a thick bead of clear silicone caulk along the seam between them, making sure it covers the area properly.

Keep adding panels to cover the entire length of the deck. To have the same overhang on both ends, you might need a larger overlap. Again, screw-down just as you did before so the entire fiberglass paneling roof is tight on top of the deck and flush against the house.


To stop any water from entering the deck between the house and the fiberglass paneling, you will need to add flashing. Take your piece of flashing and cut it so it’s as long as the roof of your deck. Now, bend it along its length. Keeping the top edge straight against the siding on your house, hammer the flashing in place against your house so the bottom half extends over your fiberglass paneling roof.

Finish with a bead of caulk at the top of the flashing where it joins the house.