First: why we won't recommend suction-cup bars
Suction grab bars are everywhere and they photograph like the real thing. Their own packaging tells the truth in small print: "balance assist only — not intended to support body weight." They're typically rated around 100–150 lb under ideal lab conditions and can release without warning when humidity, temperature, or tile texture shifts — grab-bar manufacturers themselves document the failure modes. A device that holds until the day you fall against it is worse than no device, because you'll have trusted it. If drilling is impossible (some rentals), a floor-to-ceiling tension pole rated for body weight is the honest alternative — not suction.
The four numbers that matter
- Diameter — 1¼" to 1½": the ADA standard (§609) allows 1¼"–2"; smaller suits smaller hands and arthritis grips, 1½" feels sturdier to bigger hands. Both Moen diameters comply.
- Height — 33–36" to the top of the bar for horizontal mounting, per ADA. It's a commercial standard, but it's the best-tested starting point a home has; adjust to the user's actual reach.
- Strength — 250 lb of force is what ADA requires the bar, fasteners, and wall to withstand. Note that's force, applied suddenly in a slip — which is why mounting matters more than the bar.
- Stud spacing — 16" on center: standard US framing. A 16", 24", or 32" bar spans studs cleanly; other lengths mean blocking or anchors.
The two bars we'd actually buy
- Moen SecureMount (~$35 by length) — $28–68 by length (12–42"), 1.25" or 1.5" diameter, rated 500 lb installed per instructions — with SecureMount anchors even off-stud. The off-stud anchor rating is the standout: your bar goes where your body needs it, not where the framing happens to be.
- Medline Knurled (~$22 by length) — The budget workhorse ($14–31 by length) with a textured wet-grip surface. Rating applies ONLY screwed into studs or blocking. The knurled texture is genuinely better wet than smooth chrome.
Where bars actually go
- Shower/tub: a vertical bar at the entry point (the step-over is the fall moment), plus a horizontal on the long wall.
- Toilet: a horizontal beside it, 33–36" high — or if the wall is out of reach, a safety frame brings the support to the seat.
- Not towel bars. Towel bars hold towels. If people will grab it — and they will — mount a real bar there instead.
Install reality check
Into studs or blocking: a competent DIY afternoon (drill, level, stud finder, the included screws). Into tile over hollow wall with anchor systems: read the instructions twice — the rating only holds when every step happens. Hiring a handyman runs $75–150 a bar and buys certainty; for the device whose whole job is being trusted at the worst moment, that's cheap.