Granite Slab Counters

[randynavarro]

Any published standards out there?

I'm seeing a lot of unsupported slab work in Kitchens.

No plywood or substrate, just the 3/4" slab spanning from the front rail of the cabinet to the back with nothing in between.

[randynavarro]

Never mind - just found an old thread that has some good lin

[randynavarro]

Game's back on.

Those links weren't necessarily a lot of help.

I could get the standards from the Marble Institute but it would cost $300 - not that important to me!

Anyone else have any info?

[Brad Manor]

Randy,

Not sure if this helps or not: I worked at a carpet and tile place through university (and about 5 years after). When we did granite slab counters, our rule of thumb was max span 24" and mach cantilever 12". I have that in print somewhere, if I can find it I'll post it.

-Brad Manor

[mthomas1]

The MIA standards for span and overhang are referenced here:

http://tinyurl.com/2zflsk

http://www.marble-institute.com/members ... Nwsltr.pdf

Go to page 4, "Monthly Quiz", and the answers on page 11.

[randynavarro]

Thank you Michael. That has answered my question.

How did you come about the MIA newsletter? Are you a member?

[mthomas1]

I found that newsletter a few years back when I researched acceptable counter-top spans, the DSDM is one of those things I keep looking for used, but have not run across yet.

[mthomas1]

Randy,

For future reference, this was recently posted over at inspectionnews.com

------------

"From the Design Manual produced by Marble Institute of America.

Residential Stone Counter Top Installation

- 2.17 Spans & Overhangs

- 2.18 Stone counter tops under 1-1/8" thick should not span more than 2'-0" between support centers. Spans should always be minimized. 3/4" counter tops should be installed on underlayment.

- 2.19 Unsupported overhangs shall not exceed 6" on 3/4" counter tops or 10" for 1-1/4" counter tops. In an overhang condition, the supported area must be firmly secured and properly anchored to insure the unsupported area, when loaded, will not cause failure of the setting material. Mechanical anchors and gluing are recommend for overhang supports. If overhang exceeds the maximum amounts, proper brackets, legs or other rigid support must be added by the cabinet maker of builder"

http://www.inspectionnews.com/ubb/Forum ... 00469.html

[hausdok]

2.19 Unsupported overhangs shall not exceed 6" on 3/4" counter tops or 10" for 1-1/4" counter tops. In an overhang condition, the supported area must be firmly secured and properly anchored to insure the unsupported area, when loaded, will not cause failure of the setting material. Mechanical anchors and gluing are recommend for overhang supports. If overhang exceeds the maximum amounts, proper brackets, legs or other rigid support must be added by the cabinet maker of builder"

Hmmm,

Not to get things off-track here, but I don't think a countertop can issue an insurance policy for anything. I'm sure the author meant to say ensure. I'll bet more than a few of us make this same mistake.

OT - OF!!!

M.

[Jerry Simon]

Even more off track, does anyone hear client complaints about the difference in the grain colors of the granite? Seems like I hear such about half the time.

[n/a30]

grain colors? and other non-essentials.

Max Factor has all you need to know about cosmetics. We don't inspect for that unless it somehow becomes a "very sensitive issue." Let the women cluck over the minor trivialities in their nests. It may be more important to them.