Use small toggle bolts to fasten bath accessories to fiberglass or plastic tub and shower surrounds. Avoid cracks and pullouts with these simple installation guidelines
Mark the hole positions and drill 3/8-in. holes through the fiberglass. For a clean, chip-free hole, use a brad point bit.
A brad point bit cuts a clean, sharp hole exactly where you want it without chipping, tearing, or wandering.
Run a light bead of silicone caulk around the holes and insert the toggle bolts.
Tighten the toggle bolts. Hold the mounting bracket away from the wall as you turn the screws; otherwise the toggle will simply spin inside the wall.
Use a brass screw for the toggle bolt rather than steel to avoid rust.
Fastening towel bars, shelves or hooks to a fiberglass or plastic shower surround can be tricky. The surround is simply too thin to hold screws and there's often a gap of 1 in. or more between the surround and the wall studs behind it. But with 1/8-in. toggle bolts, you can mount most light-duty hardware (like the adjustable showerhead bar shown here). Keep in mind that this leaves big holes (3/8 in.) in the surround that can't be patched later, so anything you mount will have to stay there permanently. The mounting system shown here isn't strong enough to support the full weight of a person, so we don't recommend it for installing safety grab bars.
Photos 1 – 3 show how to use 1/8-in. toggle
bolts in a surround. Everything you need is
available at home centers and hardware stores.
Here are some pointers:
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
You'll also need a 3/8-in. brad point bit
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.