Grab bars on fiberglass tub-showers and walls without studs

Quick answer

The walls of a one-piece fiberglass or acrylic tub-shower are a thin shell with a space behind it. The shell alone is too thin to hold a grab bar [1]. A bar can go through the shell into a stud, into wood backing behind the shell, or into anchors rated for fiberglass [1] [3] [4]. A clamp-on tub rail or a floor-to-ceiling pole skips the wall [12]. Ask the tub maker first: Kohler says not to add grab bars to its shower units unless they have “age-in-place backers” [2].

What holds a grab bar on each kind of wall

A grab bar is only as strong as its anchors and the wall it’s mounted on [12]. So the first question is what’s behind the wall.

Where to buy grab bar anchors and mounting kits

Hardware stores, home health and medical supply stores, and online stores sell these products in Canada and the US. The tables list products whose makers publish their limits and the walls or tubs they fit. The figures come from the makers’ pages and instructions, linked in the sources. We haven’t tested the products ourselves.

HealthCraft’s anchor fits only its own grab bars [5], such as the HealthCraft 24 in Easy Mount grab bar (opens in a new tab). HealthCraft rates that bar at 500 lb and the anchor at 300 lb [6] [5]. Moen’s grab bar instructions allow its SecureMount anchors in place of a stud [13].

More options at Amazon: grab bar anchors (opens in a new tab) and stud finders (opens in a new tab).

Before you drill

From simpleaging.com. This checklist is general information, not medical advice.

Go through this list before anyone drills into a tub, shower or wall.

What’s behind the wall

• Studs. Find them with a stud finder. The Solid Mount’s instructions scan the drywall above the tub enclosure and mark each stud [3]. Moen says studs are usually 16 in apart [13].
• Pipes, wires and other things. Moen urges checking for plumbing, electrical lines and other obstructions, like beads of adhesive or ribbing behind some tub surrounds [4].
• Space behind the wall. Moen’s and HealthCraft’s anchors need at least 3½ in [4] [5]. The Solid Mount fits a set range of gaps [3].
• What’s above the ceiling, for a pole. HealthCraft says not to install its pole if you don’t know the structure above the ceiling [9].

Ask the tub or shower maker

• Backers. Does the model have built-in backers for grab bars, and where? Kohler shows backer locations on its specification sheets [2].
• Drilling and the warranty. Is drilling the wall allowed? What does it do to the warranty? MAAX says not following its installation instructions may invalidate the warranty [17].

Choose and install

• A rated product. The anchor or kit is rated for your wall type and thickness, and it fits your bar [4] [5].
• The weight limit. The maker’s limit is above the weight of the person using the bar.
• The maker’s tools. Moen and HealthCraft both call for a 1¼ in hole saw, carbide-tipped for tile [4] [5]. The Solid Mount says not to push hard on the fiberglass while drilling [3].
• Sealed holes. Seal them the way the maker says. The Solid Mount puts silicone around each hole to prevent leaks [3]. HealthCraft puts adhesive tape around the hole on fiberglass [5].
• A pull test. The Solid Mount’s last step is to give the bar a good pull [3].
• Regular checks. Moen says to check the bar from time to time to be sure all screws are secure [4].

Why fiberglass and acrylic walls need care

Many tubs and showers come as one molded piece, walls and all. A design manual from the US Department of Housing and Urban Development (HUD) explains the problem. The wall panels alone are “too thin to support grab bars.” They touch the stud wall only at the top, so there’s a space between the panel and the studs [1].

Drywall is hollow between the studs too [4]. The Public Health Agency of Canada says, “Grab bars must be anchored firmly into the studs in the wall” [11]. Moen’s grab bar instructions say the screws must go into a wood stud, unless you use its SecureMount anchors [13].

Alaska’s Department of Health is stricter about fiberglass. It says tubs with a fiberglass surround have an air gap between the wall and the surround. It says not to install grab bars over these walls, because grab bars must be secured firmly to studs [12].

How strong a grab bar has to be

Building rules set a strength for grab bars, but only in the buildings they cover.

• United States. The 2010 ADA Standards say a grab bar must take a force of 250 pounds (1,112 N), pushing down or sideways at any point. That covers the bar, its fasteners, its mounting and the structure that supports it. The standards apply to new and altered businesses, other public places, and state and local government buildings [14].
• Canada. The 2025 National Building Code says grab bars must resist 1.3 kN (about 290 pounds of force), pushing down or sideways. It sets this for grab bars in larger buildings, and for grab bars installed in houses. Each province and territory decides whether to adopt the code, with or without changes [15].

These rules don’t test the bar in your bathroom. They show what a grab bar installation is expected to take. Some makers rate their anchors against them. Moen says its anchors meet or exceed the ADA and the CSA standards it lists [4], and HealthCraft lists the ADA strength rule on its anchor’s data sheet [5].

Your options, from most to least wall-dependent

1. Into a stud, through the shell

Grab bars can go level, upright or at an angle, so both ends land on studs [12]. On a fiberglass shell, a screw into a stud also has to cross the gap behind the shell [1]. The Solid Mount (opens in a new tab) uses spacers that bridge the gap between the fiberglass and the stud. Its maker says this moves the bar’s load into the wall framing, not the fiberglass [3].

Its instructions drill through the fiberglass with a hole saw, slowly, without pushing hard. Each hole gets a bead of silicone to prevent leaks [3].

2. Solid backing behind the shell

Wood behind the shell gives the screws something solid. HUD’s manual says the blocking must be cut to fit snugly between the studs and the panel. It must touch the panel over the whole reinforced area [1]. Canada’s 2025 code says the same for houses: no gaps are allowed between the reinforcement and the wall material in front of it [15].

In the houses it covers, the 2025 code requires stud walls around toilets, tubs and showers to be reinforced for grab bars, now or later. With a prefab tub or shower enclosure, the code moves that area off the enclosure, to the wall beside its entrance. A note explains that these enclosures “are often not compatible with grab bars that are not fabricated as part of the enclosure” [15]. Provinces and territories decide whether and when to adopt it [15].

3. Anchors made for hollow walls and fiberglass

Some anchors go through a hole in the wall and open up behind it. HealthCraft says its anchor spreads the load onto the wall [5]. Moen (opens in a new tab) and HealthCraft (opens in a new tab) each make one that the maker says can go in fiberglass [4] [5]. The table above shows the walls, space and bars each one needs.

Moen says not to install its anchors in walls or thicknesses it hasn’t approved, in walls that are weakened or damaged, or on a curved surface [4]. Moen and HealthCraft both allow one end of a bar in a stud and the other in an anchor [4] [5].

Not everyone agrees anchors belong in fiberglass. The Solid Mount’s maker says hollow-wall anchors rely on the fiberglass panel itself [3], and Alaska’s guide (above) is against grab bars on these walls at all [12].

4. What tub and shower makers say

Check your tub maker’s instructions before anyone drills.

• Kohler and Sterling. Kohler says grab bars may be added to a shower unit “only if it has age-in-place backers.” Without them, “the wall alone will not be able to provide adequate support” [2]. Sterling sells some bath/showers “with Aging in Place backerboards.” The spec sheet for one says: “Attach grab bars at the specified backerboard locations only.” [16]
• MAAX. A MAAX installation guide says that if you add a grab bar, “additional framing or backing may be needed for support.” It also says that not following its instructions may invalidate the warranty [17].

For other brands, ask the maker whether your model has backers, and whether drilling affects the warranty.

5. Options that don’t use the wall

Clamp-on tub rails grip the side wall of the tub. Alaska’s guide says they can help when stepping in and out of a tub, and when getting up from a toilet next to it [12]. Makers don’t agree about fiberglass tubs:

• Carex calls its bathtub rail (opens in a new tab) “ideal for use on fiberglass tubs” [7].
• Drive Medical says to use extreme care with its clamp-on rail (opens in a new tab) on a fiberglass tub, and not to overtighten, because the clamp may crack the fiberglass [8].
• HealthCraft says its own clamp-on tub rail can’t be installed on fiberglass tubs [18].

So check what the maker says about your kind of tub. Clamp-on rails can also loosen. Alaska’s guide says to check the tightening nut and rubber pads often [12].

Floor-to-ceiling poles stand between the floor and the ceiling. The Public Health Agency of Canada says these poles, “securely installed,” can help steady you getting out of bed or dressing [11]. The HealthCraft SuperPole (opens in a new tab) and the Stander Wonder Pole (opens in a new tab) are held by pressure against the ceiling, with no drilling. Both can also be screwed into the ceiling joists [9] [10]. Alaska’s guide prefers poles fixed at the floor and ceiling, because friction alone is often not enough [12].

Stander says never to put its pole inside a tub or shower [10]. HealthCraft says not to put its pole where it’s directly exposed to water, and places it beside a bathtub with the base against the tub [9]. Both makers say not to install these poles on an angled ceiling [9] [10]. Neither pole is meant to carry a person’s full weight. HealthCraft says its pole isn’t, and Stander says its pole gives “minimal to moderate weight support” [9] [10].

Suction-cup bars

Suction-cup bars hold on by suction. Alaska’s Department of Health says to avoid them: they can let go at random, which makes them a fall danger. Makers may say they’re only for steadying, but a person who slips grabs whatever is there [12]. That’s why they’re not in our tables.

Costs and funding for grab bar installation

What you pay depends on the product and the work it needs. Prices vary by product, store and region, so we don’t list them. Ask for a written quote that includes installation.

Canada

Home Accessibility Tax Credit: up to C$20,000 a year

The Department of Finance Canada names buying and installing grab bars as an example of an eligible expense [19]. You may be able to claim up to C$20,000 a year of eligible renovation costs. You must be 65 or older at the end of the year, or eligible for the disability tax credit. Some family members can claim too. The work must last and be part of the home. It must also help the person get into or move around the home, or lower the risk of harm [20].

Paid work by a professional generally counts. If you do the work yourself, materials count, but your own labour and tools don’t. The CRA says an item that won’t become a permanent part of your home is generally not eligible, so ask the CRA about a clamp-on rail or a pole held by pressure [20]. Our tax credit calculator estimates what a renovation may be worth, and our Home Accessibility Tax Credit guide explains who qualifies.

Medical expense tax credit

The CRA lists “bathroom aids to help a person get in or out of a bathtub or shower or to get on or off a toilet” as an eligible medical expense, with a prescription [21]. Renovation costs can also count for a person with a severe and prolonged mobility impairment. The work must be something that wouldn’t normally raise the home’s value, and that people without the impairment wouldn’t normally pay for [21].

For 2025 and earlier, the CRA lets you claim an expense under both this credit and the Home Accessibility Tax Credit [20]. A law passed in March 2026 ends that from January 1, 2026. An expense claimed as a medical expense can’t also be claimed for the Home Accessibility Tax Credit [22]. Ask the CRA or a tax professional which credit fits. Our medical expense tax credit guide explains the rules and compares the two credits. Our medical expense tax credit calculator adds up your medical costs, takes off up to 3% of net income, and estimates the federal credit [21].

Ontario Assistive Devices Program

Ontario’s program lists grab-bars, bath and shower aids, and home renovations among the items it doesn’t cover [23]. Other provinces have their own programs. See Funding in Canada.

United States

Medical expense deduction

The IRS lists “Adding handrails or grab bars anywhere (whether or not in bathrooms)” among the changes made for a disability that don’t usually raise a home’s value, so their full cost can count as a medical expense. You can deduct medical expenses only if you itemize, and only the amount above 7.5% of your adjusted gross income [24]. Our IRS medical expense deduction calculator estimates what you might deduct and whether it would lower your tax.

Medicare

Medicare’s equipment list doesn’t cover grab bars. It calls them a self-help device, not primarily medical in nature [25]. Our guide to home modification grants and programs in the US covers other help that may apply.

Questions to ask

A contractor or installer

• What’s behind this wall: studs, backers, a gap, pipes or wires?
• Can the bar go into studs through the shell? Or on the regular wall just outside the tub?
• Can solid wood backing be added behind the shell? Would that mean opening a wall?
• If you use anchors, are they rated for this wall and this thickness? What do the makers say the finished bar can hold?
• Will you follow the tub, anchor and grab bar makers’ instructions, seal the holes and test the bar?
• Is labour in the written quote?

The tub or shower maker

• Does my model have backers for grab bars? Where are they?
• Can I drill through the wall? Does that affect the warranty?
• Do you sell grab bars or kits made for this model?

An occupational therapist or physiotherapist

• Where would a grab bar help most: at the tub entrance, on the back wall or outside the tub?
• Would a clamp-on rail, a pole, a transfer bench or a shower chair help, instead or as well?
• What height suits the person? Our grab bar height guide shows the code heights.

Safety notes and when to talk to a professional

Check what’s in the wall first. Moen says to consult a professional if the area to be drilled has electrical, plumbing or other obstructions [4].

Stay inside each maker’s limits. Use only the walls and thicknesses the maker lists [4]. When a bar and its anchors have different ratings, the lower one is the limit. Moen’s grab bar instructions mention a 500 lb weight pull capacity [13], but its anchor instructions limit use to people weighing no more than 300 lb [4].

Keep checking. Check now and then that bars aren’t loosening [12]. Drive says its tub rail often needs retightening, so check it before use [8]. HealthCraft says to inspect its pole monthly, and Stander says to check its pole daily [9] [10].

Towel bars and soap dishes aren’t grab bars. The Public Health Agency of Canada says, “Towel racks or soap dishes should never be used for support!” [11]

Avoid suction-cup bars. Alaska’s Department of Health advises against them, and says grab bars need to be securely attached into studs, or to a piece of wood that is securely attached to the studs [12].

Get help if you need it. HealthCraft suggests a qualified contractor for its pole if you’re not equipped to do the work [9].

When to talk to a professional. If someone has fallen, feels unsteady or worries about falling, talk to a doctor. A doctor can look for causes and may suggest seeing a physiotherapist or occupational therapist. An occupational therapist can watch how a person gets in and out of the tub and suggest where a grab bar, rail or pole would help.