Monday, July 23, 2012

Installing Grab Bars in Fiberglass Showers

Fiberglass shower install
  Recently I was asked if I could install bars in two fiberglass showers. Yes it is possible, usually. The reason molded fiberglass units can be difficult is the gap between the shower panels and the wall framing. Though I have seen it done, it is extremely unsafe to attach a grab bar directly to the fiberglass panel. The fiberglass wall itself is to thin to support the weight of a person pulling on the bar.
  Some fiberglass and acrylic tub wall sections are now made with reinforcing already in the walls to stiffen the fixture. If the reinforced fiberglass or acrylic wall is not specifically labeled as built for grab bars and meeting the ANSI load requirements, then additional reinforcing may need to be installed.
  One way to attach grab bars to fiberglass is to install solid wood blocking into the cavity between the fiberglass wall and the studs. This would be easy to do if done while the molded fiberglass unit is being installed. This is very rarely done unless the builder is adding grab bars right away. Another way to install the wood blocking is from the back side of the shower walls. This would involve cutting into drywall and then repairing the drywall when done. This adds considerable cost to installing the grab bars.

Solid Mount grab bar anchoring system

  The method I chose in this application was the Solid Mount anchoring system. The Solid Mount system allows the installation of grab bars into existing fiberglass shower walls. The Solid Mount installs through a 2" hole drilled into the fiberglass with a  mounting assembly that attaches directly to the stud leaving a surface to which standard grab bars can be attached.
Solid mount pads ready for grab bar

The tricky part of installing the solid mount system is locating exactly where the studs are behind the fiberglass in order to drill the 2 inch holes. If you are off on this step chances are you will be buying and installing a new shower.
The length of the grab bar and how it's to be mounted depends on how the studs are spaced in the shower area. They are seldom exactly where you would like them to be. In this job I used 16 inch grab bars and mounted one vertical and the other horizontal because of the stud spacing. The bar can also be mounted at an angle.

vertical mount

Horizontal mount

Once the 2 inch holes are drilled in the fiberglass and you discover they are centered on the wall studs it becomes a standard grab bar installation. The solid mount shafts are mounted to the studs with the included carriage bolts. The mounting plate is then screwed to the shaft and bedded into some silicone. Once the grab bars are mounted they can not be removed and then mounted into the same holes again. The homeowner was very happy with her new grab bars as she was able to enter and exit the shower with much more comfort than before.

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  1. show how to install diagonally in a fiberglass shower too

  2. The correct link to the solid mount is