RedGard vs Kerdi vs Hydro Ban: Which Shower Waterproofing Is Worth Your Money?

You get to make this decision exactly once. After the tile goes on, the waterproofing is sealed behind it for decades — or it fails quietly, and you pay for the same shower twice. Here is the honest head-to-head between the three systems homeowners ask about most.

All three products do the same job: they are the waterproof skin between your tile and your framing. All three meet the industry baseline standard (ANSI A118.10 — the TCNA writes the handbook installers follow). They differ in how they go on, how fast you can tile, what they cost, and one situation where the choice is not a preference at all. If you want the full landscape first, start with our guide to shower waterproofing membranes and what they cost. This post is the three-way fight.

The quick verdict

• RedGard — the budget standard. Cheapest, most forgiving, sold everywhere. Its weakness is you: thickness depends on the person holding the roller.
• Hydro Ban — the pro's liquid. Costs a little more, cures dramatically faster, flood-testable about 2 hours after the final coat.
• Kerdi — the sheet system. Factory-uniform thickness and the only one of the three rated for steam showers. Pricier, and fussier to install well.

RedGard (Custom Building Products) — the red bucket everyone knows

RedGard is a liquid membrane: it rolls or brushes on like thick paint over cement board, in two coats, and dries into a continuous rubbery film. A 3.5-gallon bucket runs about $184 at Home Depot — roughly $2.10 per sq ft of coverage. It is the most common waterproofing in American residential showers, and there is a reason: it is hard to mess up the concept. No seams, no overlaps, easy around pipes, niches and benches.

The failure mode is just as well known: too thin. The bucket specifies a dry-film thickness, and a coat that merely looks pink enough is not the same thing. Pros check with a wet-film gauge; most DIY failures trace back to one rushed coat. RedGard is also not a vapor barrier — it does not belong in a steam shower. Full specs are on the Custom Building Products site.

Hydro Ban (Laticrete) — the liquid that respects your schedule

Hydro Ban is also a liquid membrane, but it plays in a different league on time. Where most liquids ask you to wait a day (or more) before a flood test, Hydro Ban can be flood-tested roughly 2 hours after the final coat. On a bathroom that a family needs back, that is not a detail — that is a day of schedule, saved. It runs about $105–$115 per gallon, around $2.10–$2.30 per sq ft — close to RedGard per foot, bought in smaller, pricier containers.

It is thinner to apply, bonds aggressively, and does not require reinforcing fabric in most field applications (corners and changes of plane still get treated per Laticrete's instructions). Like RedGard, it is a water barrier, not a vapor barrier: no steam showers. You are paying the premium for speed and for a membrane that is harder to apply badly.

Kerdi (Schluter) — the sheet, the system, the steam answer

Kerdi is not a coating at all. It is a factory-made polyethylene sheet, bonded to the wall with thinset. Because it is manufactured, it is 8 mils thick everywhere — nobody's roller technique enters into it. A 54 sq ft roll runs about $125–$140 ($2.30–$2.55 per sq ft), and you should budget roughly another $1 per sq ft for the band, pre-formed corners and the matched drain that make it a system rather than a sheet.

Two things set it apart. First, Kerdi is vapor-tight — it is the correct answer for steam showers, where the two liquids are simply not rated. Second, it is only as good as its seams: every overlap, corner and penetration has to be embedded and sealed correctly, which is slower, fussier work. Done right, it is superb. Done casually, the seams are exactly where it leaks. Schluter publishes the full system details at schluter.com.

Head-to-head: what actually differs

• Material cost for a typical shower: RedGard ~$180–$220 · Hydro Ban ~$200–$260 · Kerdi ~$280–$420 with components. Real money, but small next to the tile and labor it protects.
• Time to tile: Hydro Ban wins by a day. RedGard needs its coats cured; Kerdi can be tiled the next day once the thinset sets.
• Steam shower: Kerdi, full stop. Neither liquid is rated for it.
• Forgiveness: liquids forgive odd shapes and first-timers; Kerdi forgives nothing at a seam but never varies in thickness.
• Warranty: Kerdi's strongest card is the matched system warranty — membrane, drain, corners and band from one manufacturer. Mixing brands works, but the warranty paper gets thinner.

So which one goes in my own shower?

Steam shower: Kerdi, no debate. Standard shower on a tight schedule: Hydro Ban. Standard shower, sensible budget, an installer who measures film thickness and flood-tests before tile: RedGard, and I would sleep fine. Notice what is not on that list — a brand that saves a badly built shower. In seven years of tile work I have never torn out a shower that failed because the homeowner picked the "wrong" one of these three. Every failure was installation: thin coats, unsealed corners, no flood test. The installer is the waterproofing. The product is just his tool — which is why our shower remodels name the membrane, drain and flood test in writing before tile starts.

Already seeing stains, a musty smell, or soft spots? That is a diagnosis problem, not a product problem — read what to do when a shower leaks through grout. And if you are pricing the whole project, our bathroom remodel calculator and the Twin Cities cost breakdown put real numbers on every line.

Getting quotes and one installer says "we waterproof it" without naming a system? That silence is your answer. Send us your project details and we will spec the waterproofing by name — membrane, drain, flood test — before a single tile is set.