Double Vanity Upgrade
Handis double vanity upgrade is the single-sink-to-double-sink master-bath expansion that ends the morning sink-share for two people in the same household — from $2,500 for a 60-inch double on existing drywall plus the licensed plumber's separate invoice on the second-sink rough-in, to $6,000 for a 72-inch fully custom shaker double with templated quartz and dual sconces. The single-sink master vanity where two adults brush their teeth at the same sink every morning, where the kids fight over who gets the mirror, where every routine is a queue. The fix is one wider cabinet, two sinks, two mirrors, two sconces — and the licensed Washington L&I plumber's half-day to rough in the second drain and the second hot-and-cold supply. Handis runs the carpentry, the cabinet set, the scribe on both wall ends, the templated countertop with two sink cutouts, and the dual-mirror finish. The plumber's scope is named line by line on the quote.
Service
What Does a Double Vanity Upgrade Include?
Double vanity upgrade is the master-bath expansion from a single-sink vanity to a 60, 66, or 72-inch double vanity with two sinks, two mirrors, and (usually) two sconces — from $2,500 plus the licensed plumber's separate invoice on the rough-in scope. Two to three working days end-to-end including the plumber's full day on the second-sink supply and drain rough-in. The biggest single-project storage update Handis runs on this hub — and the one with the largest plumber scope, because adding a second sink means new in-wall supply and drain lines that did not exist before. Work breaks into Handis carpentry scope, licensed-plumber scope, and the project coordination Handis owns end-to-end.
Handis Carpentry Scope — What We Do
Demo of the existing single-sink vanity and top, debris out of the house. Scribe of the new 60, 66, or 72-inch double cabinet to both walls (most master-bath vanity runs sit between two walls, and both end panels need a compass-scribe transfer to close the wall gap without a tapered caulk-fill that reads as off in six months). Shim the toe-kick to level along the entire long run (a 72-inch cabinet on a sloped bathroom floor reveals the slope by a quarter-inch or more across the run — every cabinet face has to plumb up off the same level reference). Install the templated countertop with two sink cutouts, set both sinks (undermount epoxied and clamped from below, or drop-in laid in on silicone), set both faucets on the deck. Hang two mirrors centered over each sink with a level cross-reference between the two, center two sconces above the mirrors. Final re-caulk of every wet-zone joint in 100 percent silicone.
Licensed Plumber Scope — The Larger Sub on This Hub
The licensed Washington L&I plumber handles the second-sink in-wall rough-in — the new drain stub coming out of the wall at the correct height and offset for the new sink, the new hot-and-cold supply lines stubbed out of the wall at the correct height with shut-off valves, the trap and drain assembly install on both sinks, the supply line connection on both faucets, and any required permit. On a 60-inch double the second sink is typically 30 inches from the first (matching the symmetric layout); on a 72-inch double the symmetric layout puts the second sink 36 inches off the first. The plumber pulls the permit for any work that requires one and carries their own L&I trade warranty on their scope. The plumber's full day usually lands as day two on the schedule, between the cabinet dry-fit and the templated top return.
Cabinet Width — 60 vs 66 vs 72 Inches
Three standard sizes that fit most Seattle master baths. 60 inches is the smallest that comfortably fits two sinks (each center 30 inches from the cabinet end, 15-inch sink-to-sink gap in the middle). 66 inches adds counter space between the two sinks (sinks at 33 inches from each end, 21-inch gap). 72 inches is the most generous (sinks at 36 inches from each end, 27-inch gap, with room for full toiletry trays beside each sink without crowding). The size we recommend depends on your master-bath wall length and how much counter space you want between the sinks. Most Seattle master baths fit a 60 or 66; a 72 needs at least 80 inches of wall to comfortably scribe.
Templated Countertop — Two Sink Cutouts Off the Set Cabinet
Templated quartz or stone tops template off the cabinet as it actually sits (after the scribe and the shim), with two sink cutouts marked and cut at the fabricator's shop. We set the cabinet on day one, the templater measures day two after the plumber's rough-in is in place, the top fabricates in 1 to 2 weeks, and we return for the install and final plumbing connections on day twelve to sixteen. Stock standalone double-vanity tops (less common but available in 60-inch carrara marble or 60-inch white quartz) install with the cabinet without a template wait, but the size and finish options are limited.
How a Double Vanity Upgrade Works
Six sequential steps from booking-call layout planning through final dual-mirror walkthrough — the actual sequence we follow on every single-to-double vanity expansion.
Plan the Second-Sink Location with the Plumber
We confirm the existing vanity width, the new double cabinet width (60, 66, or 72 inches), and the second-sink location relative to the first. The licensed plumber reviews the in-wall framing, the existing supply and drain rough, and the route for the second drain stub. The plumber's full day is scheduled on the calendar for day two of the project.
Demo the Existing Vanity, Prep the Wall for the Rough-In
Water shut off at the bathroom isolation valve or at the building main. Existing single-sink vanity, top, and sink lifted out as one assembly where possible. Drywall opened where the plumber needs access to add the second drain stub and the second hot-and-cold supply. Debris on a drop cloth, out to the hallway, out of the house.
Licensed Plumber Day — Second-Sink Rough-In
The licensed Washington L&I plumber adds the new drain stub at the correct height and offset for the second sink, the new hot-and-cold supply lines with shut-off valves at the wall, and pressure-tests every connection. Plumber leaves the rough capped and pressure-tested. Drywall patched and primed before the cabinet returns to the wall.
Dry-Fit and Scribe the Double Cabinet to Both Walls
Dry-set the new 60, 66, or 72-inch double cabinet. Scribe both end panels to the actual walls (a compass-scribe transfer and a belt sander on each end) — bathroom corners are rarely 90 degrees on either end. Shim the toe-kick to level along the entire long run, plumb the cabinet face with a 4-foot level, secure to the wall with stud anchors or rated toggles every 16 inches.
Template the Top, Fab Lead Time, Return for Install
Templater visits the day after cabinet set to template the templated quartz or stone top with two sink cutouts measured to the cabinet as it actually sits. Fab time is 1 to 2 weeks. We return for the top install and final plumbing connections on day 12 to 16.
Install Sinks, Faucets, Mirrors, Leak-Check, Walkthrough
Top set on the cabinet. Both sinks set (undermount epoxied and clamped from below, drop-in laid in on silicone). Both faucets set on the deck. Plumber returns for final supply hookups and trap connections on both sinks; water back on, every connection leak-checked at the supply stop and under the cabinet. Two mirrors hung centered over each sink with a level cross-reference. Two sconces centered above the mirrors. Final re-caulk in 100 percent silicone. Walkthrough with the homeowner.
Double Vanity Upgrade Pricing
Final pricing is Handis labor plus countertop material plus the licensed plumber's separate invoice on the second-sink rough-in. Templated stone tops add fab lead time. Sconce install adds licensed electrician if a new circuit is needed. Request a free estimate for an accurate quote.
Tell us the master-bath wall length and the double-vanity width you want — we will quote Handis carpentry, the plumber rough-in, and the dual-mirror finish.
Why Handis for Double Vanity Upgrade
A double vanity upgrade is the biggest single-project storage update we run on this hub because it is the only one that adds an entire sink — a second supply line, a second drain stub, a second trap, a second faucet — to a bathroom that has gotten by with one for decades. The carpentry is straightforward; the plumbing is the real scope change. We have done enough double-vanity upgrades to know exactly how the in-wall framing reads, what the plumber's hours look like on a typical second-sink rough, where the drain offsets have to land for a symmetric layout, and how to schedule the templated top so the project does not stall waiting on quartz fab. The end result is a master bath that two adults share at 7 a.m. instead of negotiate over.
Honest plumber call on every second-sink rough
A double vanity adds an entire sink, which means new in-wall supply lines and a new drain stub — neither of which existed before. That work routes to a licensed Washington L&I plumber on every double-vanity project; there is no handyman-scope shortcut around it. The plumber's full day on the rough-in is named on the quote line by line — drain stub, hot-and-cold supply, shut-off valves at the wall, both-sink reconnects on the return visit. You see Handis carpentry scope and licensed-plumber scope as two distinct line items on the same project.
Scribed both ends — symmetric layout across the long run
Most master-bath vanity runs sit between two walls and a 60 to 72-inch cabinet needs both end panels scribed to the actual walls. We compass-scribe both ends before the cabinet goes to the wall for good, shim the toe-kick along the entire long run, and plumb the cabinet face with a 4-foot level. The cabinet sits flush against both walls, the doors hang square along the entire run, the top sits flat across all 60 to 72 inches. No tapered shim line on either end.
Templated top off the set cabinet — not off the cabinet drawing
Templated quartz and stone tops template to the cabinet as it actually sits after the scribe and the shim, not to the cabinet drawing or the spec sheet. The few sixteenths of an inch that the scribe added on each end show up correctly in the template, the two sink cutouts land precisely centered over the cabinet's mounting points, and the top sits flush at every edge with no gap to fill. We schedule the templater the day after the cabinet set so the dimensions are accurate.
Two mirrors leveled to a cross-reference — not just individually plumb
A double vanity reads as off if the two mirrors are individually plumb but hung at different heights. We level both mirrors to a single cross-reference line snapped across the wall (laser or chalk), center each mirror over its sink, and verify the mirror tops align horizontally before any anchor goes in. Two sconces above the mirrors get the same cross-reference treatment — same height, same horizontal spacing from the mirror edge, symmetric across the long run.
Stud-anchored heavy cabinets, rated toggles where needed
A loaded 72-inch double vanity with quartz top weighs 400+ pounds. We anchor into the studs wherever they line up with the cabinet's hang rail. Where the studs do not line up, we use rated heavy-duty toggles (Toggler Snaptoggle 75-lb minimum) every 16 inches along the rail. Never the wall plugs that come in the cabinet hardware kit — they pull out of drywall under the loaded weight of a quartz top and a stocked vanity within months.
Insured, background-checked, one-year project warranty
Handis carries general liability and workers' compensation; every technician is background-screened before the first job. The one-year project warranty covers our scope — cabinet set, scribe and plumb work, countertop install, dual sink install on the carpentry side, dual mirror and sconce hang, and re-caulk. If a cabinet door sags out of square, an end panel pulls away from the wall, a mirror anchor loosens, or a re-caulked joint fails within the year, we come back and fix it at no extra charge. The licensed-plumber portion carries the plumber's own Washington L&I trade warranty on the rough-in and supply scope, named on the quote.
Estimate
Tell us the existing single-sink vanity width, the master-bath wall length where the double vanity will go, the double-cabinet width you want (60, 66, or 72 inches), the countertop choice (stock or templated quartz/stone), and any known constraints — an out-of-square corner, tile flooring you want to preserve, a previously moved supply line. We send a clear estimate with the licensed-plumber rough-in scope called out separately.
Customer Reviews
Double vanity upgrade reviews from real Handis customers.
Master bath in our 1998 Issaquah house — single-sink vanity for 25 years, finally upgraded to a 66-inch double. The plumber came in for a full day on the second drain and the second supply (drywall opened, framed-in, capped, pressure-tested). Handis set the templated quartz top with two undermount sinks. Three weeks end-to-end including the top fab lead time. No more morning sink-share.
72-inch custom shaker-front double in our Mercer Island master. The bathroom wall is about 80 inches long and one corner is out of square by maybe 4 degrees. They scribed both end panels and you cannot see a single shim. Two sinks, two mirrors leveled to the same cross-reference line, two sconces centered. Looks like a magazine photo every morning.
60-inch stock double with a stock standalone marble top in our 1962 split-level master. No fab lead time on the top because it was an in-stock size. Handis set the cabinet day one, plumber rough day two, top and final plumbing day three. Three working days total, came in at the low end of the quote. Mirror placement is dead-centered over both sinks.
The plumber sub on our 72-inch double had to route the second drain around an existing duct in the wall cavity. He showed us the route before he opened drywall — added two hours to his day, no surprise on the bill. Handis kept the cabinet set on schedule and the templater landed on day two as planned. Communication was the best part of the project.
Coordinated upgrade — 66-inch double vanity at the same time as new bathroom tile floor in our Wallingford guest bath. Handis handled the carpentry and the carpentry coordination with the tile setter; the plumber handled the rough; everything finished in eight working days. Two sinks where there was one, brand-new tile under it, all on one project.
Frequently Asked Questions
Common questions about single-sink to double-sink bathroom vanity upgrades.