How to Install Grab Bars on Tricky Surfaces

hand holding metal bar mounted on tile wall by sink
  • 1-3 hours
  • Intermediate
  • 35-350
What You'll Need
Grab bar
Ceramic drill bits
HSS drill bits
Strap-Toggle anchors
Screwdriver bits
Piece of wire
Silicone sealant
What You'll Need
Grab bar
Ceramic drill bits
HSS drill bits
Strap-Toggle anchors
Screwdriver bits
Piece of wire
Silicone sealant

Grab bars come in various sizes, lengths, and shapes, and some of them are adaptable to many possible angles and positioning. The challenge is to install them securely enough to support your weight if you need them, without damaging the surface of your tile, drywall, or other interior finishing. Here's how to approach the challenge of applying support bar mounts to different kinds of walls.

1. Identify the Type of Wall

Solid Walls

In these walls, the framing is covered with boards or wood sheeting under the drywall. This is easy to notice—when the drill stays firm right through while drilling a pilot hole, you're probably dealing with a patch of solid wall.

Hollow Walls on Studs

These are also easy to find. When the drill easily busts right through while drilling the pilot hole, the wall is probably hollow. If you want to fasten to the studs, you’ll have to resort to using a stud finder to locate the two or three studs you’ll be using. This is also an easy enough installation but with two downsides—it limits where you can position the bar to where the studs are placed and limits the angle if your want your bar to be tilted.

Ceramic or Porcelain Wall Tiles

These are found in many bathrooms and can be a bit more difficult to work with without the proper technique.

Hollow Walls Without Backing

These don’t provide the solid lumber to secure the bar. Instead, offering only the thickness and strength of gyprock, it requires a special anchoring system.

Hollow Walls with Batt Insulation

This surface creates another challenge. Insulation can hinder the proper functioning of the anchors rotating into position.

wall anchor fasteners

2. Choose the Right Fastener

The best fastener for many support bars is the strap-toggle type anchor, as the 3/16” toggle can provide an ultimate shear load capacity of approximately 285 lbs (70 lbs allowable) on a 1/2” wallboard. Since load capacity will vary between manufacturers, remember to verify the shear load capacity of whichever anchor you choose, especially if you go with one that has a smaller footprint.

3. Install Anchors on Tricky Surfaces

Those are the surfaces usually known as hollow walls, worst so when covered with ceramic, porcelain, or some natural stone tiles, or in special cases, even floor tiles which are even thicker and harder.

Step 1 - Pick Drill Bits

Get a set of different size ceramic tile drilling bits or at least a 1/8” and a 1/2” size bits. A 3/8” size bit to enlarge the hole before the final 1/2” boring would also add to the lifespan of your larger bit (Figure 6). Use regular HSS bits if there are no ceramic or such tiles.

bathtub with natural tile and metal grab bars

Step 2 - Prep Cooling Water

You will need a small dish filled with cold water to cool the drill bit while drilling (Step 3.7) for drilling ceramic only.

Step 3 - Mark Drill Spots

Using a fine point marker, mark the spot on the tile where you need to drill the hole, making sure that none of the holes will be on a grouted joint.

Step 4 - Mount Bit

Insert the 1/8” bit into the drill chuck and secure it in place (Figure 6).

Step 5 - Prep Drill Site

Bringing the tip of the drill bit on the mark, start drilling while applying only light pressure on the drill perpendicular to the surface to create a small indent to prevent the bit from slipping.

Step 6 - Drill

Once the tip is firmly sitting in the position, you can increase the pressure and drill the hole. If drilling through ceramic, make sure the drill bit doesn’t get excessively hot because it could melt the weld, letting the tip come loose and fall off.

Step 7 - Cool and Repeat

Before the bit starts changing color drilling ceramic (to bluish), dip the tip of the drill bit in the cold water to cool it down, then resume drilling and repeat the cooling process until the hole is drilled through. If the drill bit is in at least 1-inch deep and still into something solid, you’re on a solid wall or a stud.

If the surface isn’t ceramic, proceed to Step 14.

Proceed to Step 8 for the ceramic wall.

Step 8 - Enlarge the Hole

Replace the drill bit with a 3/8” and redrill the same hole being more careful not to damage the surface as you follow the previous steps 6 and 7, just deep enough to get through if the wall behind is solid or right through all layers if the wall is hollow.

In a solid wall, proceed to screw the bar in and go to Step 14.

If you hit a hollow wall, keep going through the following steps.

Step 9 - Probe With Wire

If the drill bit went through a hollow wall, it offers the flexibility of placing the grab bar anyway and anyplace you want. Insert a piece of stiff wire curved at 90° in the hole and feel around to make sure that the hole is at least 1-inch away or directly on top of a stud, in which case you may want to relocate one way or the other. The wire could also tell if there is batt insulation inside the wall.

Step 10 - Enlarge the Hole Again

Replace the drill bit with a 1/2 “ bit to enlarge the hole big enough to insert a 3/16” or 1/4” strap-toggle through and following the guidelines in steps 6 and 7. If the drill bit pulled out insulation while drilling, you’ll next have to deal with it.

Step 11 - Poke Insulation Away

The “fluffy” insulation inside the wall will keep the pivoting bar at the end of the strap-toggle from rotating into position, so what you have to do is create extra space behind the wall to permit the toggle to operate normally. To do this, use a large Phillips screwdriver (because it offers a large and somewhat round tip) and insert it into the hole where you can use it to push the insulation back from the hole and enlarge a free space.

By moving the screwdriver around, try and create as much space as possible to provide an adequate flat surface on the underside for the strap-toggle bar to sit against, and install the toggle before the insulation works its way back.

Step 12 - Mount Strap Toggle

Insert the strap-toggle into the hole and pull it back while the bar rotates in position.

Tip: If the bar does not properly pivot into place, you can help it by inserting a skinny rod or screwdriver next to the toggle and pushing the up-part of the bar back into pivoting. This may require several tries.

Step 13 - Set Toggle Straps

Push the flange on the toggle straps right up against the wall surface to hold the toggle in place, then break off the straps.

wall toggle strap anchor mount with screws

Step 14 - Mount Grab Bar

Attach the grab bar to the wall through that hole or strap-toggle but leaving it loose enough to move about, place the bar in position using a spirit level or at an angle, and mark the location of hole #2 and follow-through from Step 3 forward.

Step 15 - Tighten Fasteners

Attach the other end of the bar to this strap toggle and tighten lightly in place against the tile wall. Make a mark for each of the remaining holes, move the bar out of the way and follow all the same procedures to drill the rest of the holes.

You can finally apply white or clear silicone behind the fastening brackets and install the grab bar without a second thought.