undermount kitchen sink

[pitterpat]

You guy's and gals have any good tips on installing an undermount kitchen sink? This will be on granite, quartz or Corian like solid surface? Also how about pricing....$900 - 1000 US. Any books, links or articles as to the best way to do this?
Tks

[jimbo]

Work closely with your granite installer. And forget about attaching any mount clips to the granite; not a good idea.

Amer. Std, and Kohler, as well as some generics, make undermount bracket kits. These take the form of bars supported by the cabinet sides, or front-back. They and the sink are installed before the granite. Then after the countertop is on, adjuster screws snug the sink up to the countertop ( with a bead of caulk of course.) Very easy to do, sink is extremely secure, and the sink can be removed if necessary in the future without disturbing the top.

[jadnashua]

On the three undermount sinks I have in my place (I used the same granite fabricator for all of them), they use a router bit to make T-slots. You slide the T-bolts into them, and using clips, snug the sink up after putting on the silicon. Works fine. Now, if it was a heavy cast iron sink, they might do it differently (two porcelain bathroom sinks and one SS kitchen sink), I don't know, cause I don't have one! The fabricator I used charges $300 for a simple kitchen sink including polishing the edges, T-slots, and faucet holes, and $250 for a vanity.

[finnegan]

If you are installing the sink prior to the counter, you can build a frame within the cabinet, lvel the top of the sink to the top of the cabinets and set the sink in silcone just to keep it in place. The counter top guys will take it from there.

[spitz]

How would I go about replacing an existing undermount sink? The counters are granite and the sink has already been installed. Would I just disconnect the plumbing, unscrew the bracket mounts, pry away the sink (caulked on) and reattach the new sink in the same drilled holes from the old sink?

[master plumber mark]

you are far far better off to let the granite guy

provide and install the undermount sink........


most granite guys around here will do it fro free
cause they need the sink to
make a templatte anyway to cut it out.....


jsut let them do it ---no matter what the cost.....

you will save yourself tons of grief and misery trying to do his job

[Kristi]

well I've installed a few, and haven't found them to be that big of a deal. I don't like giving all my good secrets away, but here goes another

- the countertop can be set ontop of a plywood "undertop" (new term made up on the spot)

- silicone the rim of the sink

- measure and set an abs leg that will jam the sink up against the granite while the silicone sets - clean up that gooey inside edge and make sure she's centred beautifully!

- run steel strapping (4 long strips) - 2 from left to right, 2 from back to front (a strap on either side of the drain, of course, in each direction); screw the strapping tight to the plywood

- remove the abs leg the next day and hook up the drainage. you're good to go!

[jadnashua]

My granite fabricator uses a router (probably on a cnc machine) to cut angled T-slots in the underside of the slab. Slobber silicon on the flange of the sink, hold it up, center it, slide in the T-bolts with clamp, tighten and you are done. I wouldn't try this on 2cm slab, but on 3cm stuff he has the bottom of the slot maybe going through 2/3rds of the slab, so it is quite strong.

[Sherm2005g]

I am going from a formica overmount sink to a granite undermount sink. Current overmount sink is 8" deep and the new undermount is 9" deep. Accounting for the lowered placement of the new sink, will that affect the ease of re-attaching the drain pipe? And if so, how do I adjust for it?

[jadnashua]

Maybe, maybe not. Depends on the height of the arm that goes into the wall. If the sink is too low (i.e., lower than the arm), you'll have to tear the wall apart to rebuild that connection to get it lower. Water doesn't flow uphill.

[hj]

The largest part of the price is the cost of the sink, and for that you have almost unlimited possibilities. I mount the sink into the cabinets with the rim level with the bottom of the granite. The mount can either be metal saddles with adjustment bolts to raise and hold the sink, or a wooden framework attached to the cabinets. Set the sink onto the supports, apply the necessary sealant, and then put the granite top over it. The sink can be hooked up as soon as the granite guys leave.

[jadnashua]

My granite fabricator uses his CNC machine to mill T-slots in the bottom of the slab to hold T-bolts and clips which hold the sink (mostly while the silicon cures). this works fine for SS, but you'd probably want something else for a CI sink. Some fabricators drill holes and epoxy in studs, some don't do anything other than make the hole and leave it up to the plumber.

[rockymeet]

Step 1: Have a Professional Cut a Hole

Before beginning, have a professional fabricator cut the sink hole using a template. Sink bowls come in varying sizes and arrangements so you can select the configuration that best meets your needs. Think about your fixtures too. Do you want a double-handle or single-handle faucet? What about a soap dispenser? Since the weight of the sink is supported from the underside, you'll need a solid surface countertop such as granite or marble.



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Step 1: Have a Professional Cut a Hole

Before beginning, have a professional fabricator cut the sink hole using a template. Sink bowls come in varying sizes and arrangements so you can select the configuration that best meets your needs. Think about your fixtures too. Do you want a double-handle or single-handle faucet? What about a soap dispenser? Since the weight of the sink is supported from the underside, you'll need a solid surface countertop such as granite or marble.
Step 2: Test Fit the Sink

Place a 2x4 across the countertop, clamp the sink to the underside and adjust the placement. Thread the wing nuts onto the screw heads. Test fit your sink and mark the location for the mounting clips. With the sink out, drill 1/4" holes for the brass inserts and tap them in. Clean the ridge with denatured alcohol. Run a bead of silicone sealant around the edge, and re-clamp the sink in place..

Step 3: Secure the Sink Bowl

Thread the wing nuts onto the screw heads and tighten the screws to anchor the inserts. Hand tighten the wing nuts to secure the bowl. After removing the clamps, place masking tape across the back of the countertop and mark the layout for the faucet holes. Drill the holes using a 1-1/4" diamond coring bit. Allow it to cure overnight before installing your plumbing.

[geniescience]

Work closely with your granite installer. And forget about attaching any mount clips to the granite; not a good idea.

Amer. Std, and Kohler, as well as some generics, make undermount bracket kits. These take the form of bars supported by the cabinet sides, or front-back. They and the sink are installed before the granite. Then after the countertop is on, adjuster screws snug the sink up to the countertop ( with a bead of caulk of course.) Very easy to do, sink is extremely secure, and the sink can be removed if necessary in the future without disturbing the top.

Repeating what Jimbo posted, and adding a few caveats.

Work together with your stone countertop guys -- but don't assume they know best. Some of them will not leave the stone as is, and will cut it, rod it, etc. There is no need for them to do this. It increases risk. Braxton Bragg is one of the "generic" names that Jimbo referred to : Sink Setter
http://www.braxton-bragg.com/index.c...457,8580,7105/
http://www.braxton-bragg.com/index.c...457,8580,7106/
http://www.braxton-bragg.com/index.c...c/0,8457,8580/

[mtoMA2AZ]

Is it possible to REPLACE an existing undermount sink? I currently have a black enamel Kohler double sink, which no amount of cleaning gets looking good - it was like that when I bought the house. I hate it, and would like to replace it with preferably a black matte finish composite Mont Blanc or similar sink. However, I just went to Lowe's and was told it is impossible to replace a sink without installing completely new granite countertop. That there is no standardization of sink size (and therefore of the hole already cut in the current granite) etc. Is this true? That sounds ridiculous to me! It DOES look like from what you're saying above, that I WILL have to hire a granite guy to install the sink. Am I doomed to have this nasty black sink forever? Or must I go to the expense of replacing all my granite counters just to get a new sink? I wouldn't have installed granite myself; I just don't get what's so great about it. But I digress...