Cutting, polishing and installing granite (slab) countertops

[jwalko]

Hi all:

I am looking for some advice.  I am installing granite countertops in my kitchen and bar area.  I bought Verde butterfly for the bar and Baltic brown for the kitchen (I already bought these because I got a great price and couldn't pass them up).  They are 3/4" slabs w/ a full (1.5") bull nose on the front edge.

I am fairly comfortable installing cabinets and countertops, but have never worked with granite slabs before...just tiles.  I need to cut the slabs to length, miter the edge to meet the other slab at the seam and cut and polish the sink holes (I plan to use undermount sinks).

I am going to do the bar first because it is my basement.  While I want this to be as nice as possible, but if it isn't perfect, I'd rather it be in the bar area instead of the kitchen.  I have a couple of questions about the install and the tools needed.

1. My plan is to install the countertops over 3/4" plywood.  I have read of three different ways of adhering the granite to the plywood...epoxy, liquid nails and thin-set.  What is the preferrred method?  I'll be installing the cabinets in the bar area and will be able to level them out.  In the kitchen, I'll use the existing cabinets, but these should be fairly level (house is new).

2.  I plan to "rod" the granite where I'll be cutting out the sink hole.  What is the preferred method for cutting the "valley" for the rod?  I was thinking of diamond blade in angle grinder.  Is there a better way.  What diameter rod is necessary (1/4"??)

3.  In the kitchen, no matter if I measure from the wall, or from the end cabinet, the seam falls in the middle of the sink cut out.  I've read some who say this is preferred and others who say this shouldn't be done.  Any opinions?

4.  I'll need to "bull nose" one end, including laminating a piece of granite under the counter to get 1.5" height.  I was planning on using a hand profile wheel for this (one of the kits on this site)?  Is this too much for a "beginner"?

5.  I have most of the tools necessary to do all this work "dry".  Would I get a better finish if I make the investment to purchase the appropriate "wet" tools (profiler, polisher and saw)?  Can I get a professional finish using only dry polishing?

6.  I'd like to cut and polish outside, then move inside, but am worried about breakage...how concerned do I have to be moving the slabs 30-40 feet into position if I rod the sink cut outs?  I could cut and polish teh bar sink in place, because that area isn't finished yet, but I'd rather not do the kitchen in place unless absolutely necessary.

My plan to do the bar first is to actually get the experience doing this.  If I find I am in way over my head, then I can hire a professional installer for the kitchen.  I feel pretty comfortable doing this, given that I have experience working with tile (ceramic and granite), installing cabinets and regular countertops (formica and tile).  Any advice would be appreciated.

Thanks;

John

[Stone Dude]

1. you dont want to use any of those 3. liquid nails in notorious for seeping through and leaving dark spots. thinset and epoxy are overkill and too messy. clear silicone is going to be what you want to use. but you do want to use epoxy for the seams

2. we use a 4 1/2 inch angle grinder with a diamond blade to rod. some guys use rodding blades but for one time use its not necessary. we use either 1/4 or 5/16 allthread for rodding.

3. if we have to have a seam, we put it dead center of the sink. this reduces the chances of breakage during transport and install, also you have a sink so the seam is minimal.

4. i would say yes, this is too much for a beginner, but if youre gonna do the rest of the work why not go all the way. i think the hardest part about the hand profilers is keeping it level, also polishing. if you decide to do it, i would suggest waiting untill you make your cuts and practicing on whatever scrap pieces you have.

5. i dont think youre going to get a factory finish doing everything dry. if you invest the money in all the tools to do it wet you might as well hire someone to do the install for you.

6. if you have someone to help you, make sure you carry the pieces vertical and you shouldnt have any problems. when you go to lay the pieces in, lay the back of the piece against the subtop at 45 degree angle, then swing it up horizontally and slide it into place.

practice on whatever pieces you can before you do your final product. theres other people that will tell you to do it a ton of different ways. ive only told you what i know our shop does, and its not the only way to do it.

[Mark D.]

Here is another point of view for you:

1) Use 5/8" plywood instead of 3/4". Since there is no standardization in the stone industry there are times when 3/4" plywood will show beneath the lamination. As far as the adhesive? Silicone! Enough said about that.

2) Use a grinder with a 1/4" thick rodding blade. It is a time use, but if you use a thinner blade you will need to make multiple cuts to fit in a rod that is 1/4" thick.

3) That seam should be fine if it is fully supported from beneath.

4 & 5) The router bit, the dry pads and instructional DVD's can be found at www.defusco.com
We have done this many times before and taught many do-it-yourselfers how to use these router bits and to dry polish to match the factory finish.

6) The rodding will help support it while moving carefully from the work area to the install area.Just use common sense and don't transport it horizontally.

This is a do-able project for a weekend warrior, and we will help you do it! if you want to talk about the project feel free to call me at the office at 800-289-6834.

Glad to be of service,
Mark

[jwalko]

Mark, Cameron:

Thanks for the replies.  I appreciate the advice.  I am excited about this project and am anxious to get started.

Something else occurred to me last night.  For my bar, the overall width for the bar top was going to be 19" (I actually came up with that width because a 12x12 tile, when laid diagonally leaves just enough room for a lean rail with a 19" wide bar top).  I was originally going to use granite tiles.  Regardless, I was going to leave a 9" overhang for the seating area.  This leaves 5.5" for the half wall that is the front wall of the bar (built out of 2x6).  This would mean I would have approximately a 4.5" overhang on the inside of the bar (over the food prep area).  I was going to put standard cabinets in this area, so rather than have the standard 27.5-28" width for the cabinet top, I would have about 23".  It occurred to me last night that this might allow room for a sink and faucet (assuming full size undermount sink).  I was planning on a 36" sink base and I understand that it is desirable to leave as much stone in front and back of the sink as possible for strength.  So, do you have any recommendations?  Should I consider reducing the overhang behind the bar?  I might consider a smaller sink, but then you run into issues when washing glasses (I was hoping to install a double bowl sink here).  I was even thinking of mounting the faucet on the side of the sink instead of behind it, but I don't know how this will look.

I just want to make sure I consider all potential issues before getting started.

Mark, I'll be giving you a call regarding some tools.

John

[Mark D.]

John,
Maybe I misunderstood you, but did you say tiles and undermount sink in the same sentence? So you want everyone to see the plywood, backerboard & thinset under the tiles? Or maybe you are artistically covering that with strips of the stone? I am not following you on this one....
If it is slab it can be done, but I would need a drawing to understand.
If the counter is 23" deep you may need to get a spigot that pulls forward only, but the depth is not a problem as long as you get a sink that fits. the cabinet. Or did I misunderstand you?

Glad to be of service,
Mark

[jwalko]

Mark:

Sorry for the confusion.  I am going to use slabs (which I already purchased).  I was originally going to use tiles, which is how I came up with the bar top being 19" wide.  The overhang on the "inside" of the bar got me thinking about having enough room for the sink and faucet.

Since I can't draw a good picture, I'll try to describe it.  I'll have the bar top at 42" or 44" (I can't remember what I set it at...standard bar height).  The "back bar" area will be standard cabinet height (36", I believe).  There will be about a 6-8" difference between the two.  I'll fill this in with 2x4 and plywood, which will allow me to attach the back of the bar top directly to the cabinets (adding stability to the bar top, since it will be attached both to the 2x6 frame and the cabinets).  I plan on having electrical outlets installed here, since I have the room.  I'll use bull-nose granite tile just for this "wall".  The rest of the bar will be granite slab (I'll try to match the color of the slab as closely as possble with the granite tile, but if it isn't perfect, it really doesn't matter since this is the back of the bar...most people won't see it).  It is this 6" "wall" that will be overhanging the back bar area (the "food prep" area).  It will be shaped something like this, when viewed from the side

_____________    Bar Top
                      |
                      |_____________    Counter top
|-----19"-------|                          |
                                             |
                    |-----23"-----|        |
                                             |

While this drawing isn't to scale, it is the best I could do here.  I think you can see what I mean.  My concern was having enough room for the sink and faucet in the 23" span over the sink base  and still having enough granite to minimize risk of breakage (the 23" is measured from front edge to back edge...note that I'll have the bull nose in addition to the 23"...since that is overhanging the edge of the base cabinet).

How much granite (in inches) should I leave between the front of the counter (the bullnose) and the edge of the sink, and how much granite do I need to leave between the back edge of the granite and the back of the sink?  I understand that more is better, but what is the minimum I should consider if I want to minimize the risk of cracks.  I hope this makes more sense.  I am trying to decide what size sink I can purchase.  I want to get one as large as possible, but still have room for the faucet.  The problem isn't the width of the sink...it is the depth from front to back.

Thanks;

John

[Mark D.]

If you have a couple of inches in front of the sink you can make that work. Make sure the granite is fully supported from underneath. Feel free to rod the stone at the back if it is 2cm, but in front the laminated edge will give it more strength.

Remember this is a bar sink...it's not like people will be dancing in it. It really doesn't require much in the way of strength.

Glad to be of service,
Mark