Faucet, Drain and Overflow Data to Fix Before a Vanity Top Is Cut

From data sheet to locked drawing

Which data must be fixed before a vanity top is cut?

Five sets of data must be fixed: faucet holes, deck thickness at those holes, drain hole, overflow with its drain, and trap position.

Moen’s WS84228 sheet, for example, states three holes of 1-1/8 in minimum diameter, 4 in on center, and a deck between 1/4 in and 1-3/16 in thick.

In what order should the interface be settled?

Supplier first, then faucet, deck, drain, trap and remaining holes. This order is the guide’s own.

1. Name who supplies the faucet and the drain.
2. Fix the faucet model; take hole count, diameter and centers from its sheet.
3. Check the top’s thickness at each hole against the sheet.
4. Record whether the bowl has an overflow; choose the matching drain.
5. Place the drain and trap against the drawers and the wall outlet.
6. List every other hole, then lock the drawing.

A sink sheet can bind the fabricator too. Kohler’s K-2356-8 sheet says the countertop manufacturer or cutter must use the cut-out template supplied with the product, or a current one from Kohler.

What hole size and spacing do faucet makers specify?

Makers print hole count, spacing and diameter per model. On these five documents the figures are not the same:

A sink has its own figures: Kohler’s K-2356-8 sink has 1-3/8 in faucet holes at 8 in spacing.

How thick can the top be at the faucet hole?

Only as thick as the faucet’s sheet allows. These documents print a maximum, and two of them a minimum:

The Moen 6610 and WS84228 files each cover two versions; on the 6610 the maximum differs, so the version matters. Where a sheet names no kit for thicker decks, ask the maker, change the faucet or thin the deck at the hole.

Which drain matches a bowl with or without an overflow?

Check the drain against the bowl. Crosswater’s FAQ says a basin with an overflow needs a slotted waste and a basin without one an unslotted drain; it also offers universal drains for either. Kohler’s drain sheets state which they are:

With an overflow

Kohler’s K-7124-A is a pop-up clicker drain with overflow. hansgrohe’s Rebris manual says its drain is intended for a sink with an overflow.

Without an overflow

Kohler’s K-7124 is the clicker drain without overflow. For a sink with no overflow, hansgrohe refers to the sink’s instructions.

Drain hole size

Kohler’s K-2356-8 sink has a 1-3/4 in drain hole. hansgrohe says its drain suits most, but not all, lavatory sinks sold in the United States and Canada.

Lift-rod room

Moen’s WS84228 sheet covers two versions: one recommends at least 2 in to the backsplash for lift-rod operation, the other 2-1/2 in.

• Overflow: yes or no
• Drain model and type
• Drain hole diameter
• Bowl thickness at the drain
• Operation and rod clearance

What does the trap need under the top?

The trap needs height below the drain outlet and room among the drawers. One state rule and one maker show what to check:

A trap for each fixture

Wisconsin’s SPS 382.32 requires each plumbing fixture to be separately trapped by a water seal trap, with listed exceptions.

Seal depth

The same rule sets a liquid seal of 2 to 4 in unless the chapter specifies otherwise. Separately, Geberit’s UK catalogue gives a 50 mm water seal for its space-saving drain for the ONE washbasin; the two are not compared here.

Height and offset

With listed exceptions, Wisconsin limits the vertical distance from the top of the fixture drain outlet to the horizontal center line of the trap outlet to 15 in, and the horizontal distance from the drain outlet to the trap inlet to 15 in.

Room for drawers

Geberit lists that drain for washbasins without visible overflow, for a cabinet without trap cutout, and for a material thickness of 15 to 20 mm near the waste outlet.

These are examples, not general rules; confirm the trap with the local authority. This guide’s own step: draw the trap against the drawers, then move the drain, shorten the drawer or give it a cut-out.

Which standards do the maker sheets name?

The sheets name standards without an edition year. This guide did not read them.

Who supplies each datum, and when is the drawing locked?

Each datum has one supplier; the drawing is locked when every hole has a source. This is procurement guidance.

1. Buyer or plumbing supplier. Faucet and drain models with current sheets.
2. Plumbing designer or contractor. Rough-in drawing, trap type and whether an overflow is needed.
3. Cabinet supplier. Drawer positions and depths under the bowl.
4. Top supplier. Thickness at each hole and at the drain; the combined drawing.
5. Hold on a missing item. Without a model and sheet the drawing stays open.
6. Lock and sign. Every hole has a diameter, position and source.
7. Fit the first top. Mount the real faucet and waste and run water.

Why a late model change can mean a new top

A cut hole fixes diameter, centers and position, and the sheets above differ by model. Delta states on its sheets that it may change specifications and discontinue models without notice. This guide’s rule: a change before cutting means a reissued drawing; a change after cutting means checking the new sheet against the holes already cut, and a new top if they do not match.

What should you send and ask before a quotation?

Send the sheets, not a photo: a picture shows the look, not the hole, the deck thickness or the drain.

Include with your request

• Faucet and drain sheets
• Sink sheet, with any cut-out template
• Plumbing rough-in drawing
• Cabinet drawing with drawers
• List of extra holes, if any

WNS Global confirms any offered top, basin, drilling and commercial terms separately in writing. This guide does not state that WNS Global products have the hole sizes, deck thicknesses, drains, traps or standards listings named above.