IF your Fabricator is willing to guarantee that your seam wont separate from the heat cycles and vibration patterns that occur every time your dishwasher runs and heats up the glue in the seam - then hey - God Bless Him.... AND You !!!

However........Since it IS an Engineered Stone product, AND IF he's using an epoxy - and NOT a polyester to glue the seam - he's got a better chance of it lasting longer.

The "this is the way we've always done it" defense never hold up in court when the job fails - I know this as I am a Fabricator and I testify as an "industry expert witness" on lots of cases where seams fail all the time and I am brought in to show the mechanics of why some seams last and others don't........

In your case - the seam placed over a dishwasher will be subjected to daily - if not multiple times a day - heat cycles where live steam will be vented out of the dishwasher and make direct contact with the stone at the seam line. The assembly (the stone top with the seam in it) will also be subjected to vibration from the dishwasher unit dunning each time it cleans your dishes.

Combine the vibration and the heat - multiple times a day, or even daily - over time - this can weaken a seam line, and the first thing to let go would be the glue.

In your case - ES (engineered stone) is made up of epoxy glue and quartz particulate fashioned into a slab - (kind of like terrazzo). When the seams are glued - most ES manufacturers recommend that an epoxy glue be used in lieu of the more conventionally accepted polyester that most guys like me swear by when doing seams in Natural Stone.

Epoxy is NOT Polyester. Polyester is NOT Epoxy - the two are vastly different glues and react differently. Epoxy and Polyester are many times - not compatible with one another and will not bond together at an optimal rate.

IF your guy uses EPOXY in the seam directly over the DW - your installation will last longer than if he would have used polyester, but due to the placement of the seam (over the dishwasher) it'll be just a matter of time until you start to see degeneration if the seam - due to the daily exposure to the heat and vibration from the dishwahser.

It's kind of like this analogy - if you have a seam that you hit one time with a hammer - you may chip the stone - you may not... but any damage will be limited to the one time you hit the stone with your hammer.

But....... if you keep hitting the same spot in the stone over and over again with the same hammer, with the same force and the same velocity - eventually, you're going to break the stone and / or break the seam.....

At the end of the day - why would you want to hit the stone with a hammer to begin with?

I don't mean any disrespect to your Fabricator, but I'd suggest keeping the seam away from the dishwasher and going with two seams. IF he's good - and uses a Seam Phantom and Gorilla Grips to dress & set his seams - you will prolly not even see the seams - or at the very worst - you'll struggle to find them every time you go looking for them - remember that ES seams are harder to notice that Natural Stone ones - primarily due to the monolithic nature of the color distribution within the slab......

If on the other hand - he's never heard of the Seam Phantom OR Gorilla Grips or doesn't have either - well, your seams will be much more noticeable :-0

just my .02 cents worth =

hth

kevin

lynn85,

OTOH, here is free information that might help you develop a sense of comfort with the opposing point of view. A steel flat bar running the length of the counter run is easy to buy, and easy to install, too. It braces the front end. Then the counter material can rest on one continuous line parallel to the counter's long side, instead of on multiple separate lines (cabinet sides). I have this. I have two parallel steel flat bars running the entire length of my cabinet run. Together they hold the entire cabinet assembly in a long and perfect rectangular block. My writing this out is not a recommendation to install this. It's information, about the block under the quartz counter, in my kitchen. (No I do not have a seam in the same spot as yours.)

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Two more things along the lines that Kevin described.

2.) in this context, anyone who says "for years" probably means that they've done something kinda similar, once, or maybe something more like "We are usually willing to do stuff that more cautious people don't do or won't do"

1.) I read "We have found the granite/quartz clips that attache under the dishwasher to then screw into and we have put a brace on the wall behind the dishwasher so there is support for the quartz and for the installer to use to line up the seam."
This tells me that YOU are doing too much work, to compensate, to enable, to allow the other party to feed into your eagerness. And that the other party isn't doing enough, to take responsibility, to be in charge. I mean, what I read is that YOU found the clips. Huh?

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Don't over-rely on any internet information.

Hth

Check to see if your DW has an installation option to go through the sides. Mine die (Miele). If so, do that and then put a support over the DW at the front.

Only an inexperienced fabricator would offer that and he probably won't be in business long enough to give you the repair service that you will inevitably need down the road.

Some DW produce no steam (none vented), but there are vibrations and heat cycling. Nobody can tell how much this will affect a quartz seam. The manufacturers of the quartz material can be contacted. Call them. They DO have training guides that specify what to do. They can tell you if seams need to be within X inches of a cabinet side.