Toto Home Additions & ADU Nationwide

Toto Home Additions & ADU: The West Palm Beach Owner’s Guide

Toto bathroom fixtures are specified in most West Palm Beach home additions and ADU projects we quote, with installed costs for Toto-equipped additions running $45,000-$130,000 and ADU construction at $90,000-$220,000 depending on plumbing rough-in complexity and fixture count. We stock Toto Drake, Ultramax, and Aquia series toilets, along with compatible fill valves, flappers, and trip levers on our West Palm Beach trucks. Most Toto part replacements are completed same day once the model number is confirmed.

Call (561) 475-3903

Homeowners usually discover a Toto part issue during the final punch walk or within the first six months of occupancy - a soft-close seat that won’t stay up in the humid West Palm Beach air, a fill valve that hisses because the city water pressure runs higher than Toto’s 80 PSI maximum, or a flapper that warps prematurely from chlorine exposure. These aren’t defects; they’re maintenance realities in a coastal Florida environment.

Which Toto Models This Applies To

Toto stamps a four-digit CST or MS number inside the tank lid and on a label behind the bowl - that’s the identifier we need before we load the truck. The Drake II (CST454CEFG) and original Drake (CST744S) use a 3-inch flush valve and THU500S flapper, while the Aquia dual-flush line (CST412MF) runs a 2-inch valve with a distinct flapper carrier that doesn’t interchange. Ultramax II (MS604114CEFG) and Carlyle II (MS614114CEFG) are one-piece designs with proprietary fill valves; the Korky 528T aftermarket works, but the genuine THU500S maintains the factory water level spec.

We carry both OEM and quality aftermarket for West Palm Beach customers. The Korky 528MP fill valve fits 99% of Toto two-piece tanks and costs less, but the genuine THU500S includes Toto’s calibration for the 1.28 GPF flush cycle. For rental ADUs or owner-occupied additions where water bills matter, we spec OEM. For quick-turn investment properties, aftermarket with a one-year warranty. We note the choice on the written quote - Clause 1 of the Haven Standard means the price is set before anyone touches a tool, including which part grade you’re getting.

Signs Your Toto Home Additions & ADU Is Failing

• Constant hissing or running water - The fill valve diaphragm hardens in West Palm Beach’s chlorinated municipal supply, losing its seal against 65-85 PSI pressure common in Palm Beach County. The valve can’t fully shut off, so water bleeds into the overflow tube 24/7.
• Weak flush or bowl streaking - The flapper loses flexibility in heat and chlorine, closing too fast and releasing only a fraction of the tank’s 1.28 or 1.6 gallons. Toto’s siphon-jet design depends on that full volume; partial release defeats the engineering.
• Double-flush required - On dual-flush Aquia models, the flush tower seal degrades and the half-flush mechanism hangs up. Owners press twice, using more water than a single standard flush would have.
• Seat loosening or soft-close failure - The plastic hinge bushings expand and contract with West Palm Beach’s humidity swings, particularly in unconditioned ADUs or pool bathrooms. The soft-close damper then slips or cracks when the seat slams.
• Handle goes slack or sticks - The trip lever corrodes at the brass nut where salt air reaches it, or the chain kinks where it contacts the flapper. Both are cheap parts, but the symptom often masks a failing flapper that’s overworking the mechanism.

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Replacement Cost & What’s Included

The range depends on three factors: whether we can source the part same-day from our West Palm Beach warehouse (most common items) or need to order from Toto’s Morrow, GA distribution center (adds 2-3 days), whether the shutoff valve and supply line need replacement too, and whether the toilet is on a slab or raised subfloor - slab-mounted bowls take longer to reset properly. Every quote is flat price, line-item, with the part grade named. Under the 365-Day Done Right Promise, if the flapper weeps or the fill valve sings inside a year, we return and correct it.

DIY or Call Us?

There’s nothing dangerous about a toilet tank - no high tension, no electrical, no gas. A homeowner with channel locks and a sponge can swap a flapper in ten minutes. Where DIY goes wrong is misidentifying the model and buying the wrong part, then making two trips to the West Palm Beach hardware store while the toilet runs. The 3-inch versus 2-inch valve distinction trips up most first-timers; so does the Aquia’s dual-flush carrier, which looks like a standard flapper but isn’t.

We recommend calling (561) 475-3903 when you’re mid-project on an addition or ADU and can’t afford the delay, when the toilet is on a concrete slab and you’re not confident in the wax ring reset, or when you’ve already tried once and now have a mismatch of old and new parts in the tank. We’ll confirm the model number over the phone, quote the repair flat, and schedule around your inspection timeline.

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