No cook top, just a sink on this one. I thought it should go through the sink but installer says no. I thought it would be better to have a small seam...?

Maybe Joe will chime in. I'm not sure why it can't have it through the sink?

Through the sink or the cooktop is a common place to make a seam because the seam itself is shorter. A divide through the large cutouts also makes it easier for the installers to get it in without breaking a narrow bit. OTOH, the other point of view is that right there front and center will just draw your eye to the seam. The actual answer is that there isn't a "correct" place to put it, just a place that suits you. We went with a seam off to the side.

We have one in the middle of the sink and one in the middle of the cooktop. Honestly, I don't even see them any more. I think I might notice them more if they went from front to back just though the countertop material, but sometimes that's the only way the layout works.

I depends on the size of the raw material and the required fabricated size. Most fabricators let yield dictate seam placement because it makes them most cost competitive. There is really no "wrong" place for seams, there are only tradeoffs.

My fabricator would not do a seam at the sink. They put support over my dishwasher area and that's where my seam is. It was hardly noticeable after install and I don't even see it anymore. They did a great job. We have Black Pearl leathered Granite. Perhaps your countertop choice will play a part in addition to your installer as to how much the seam will show.

My single seam is through the sink. So minimal, hardly notice it.

Our fabricator gave us the option of shorter seams (front + back) at the sink. We opted for a longer seam to the left of the sink (a lesser used area): too much potential for gunk to build up at a sink seam -- yup, that'd be me there w/ my toothbrush!

If your fabricator uses Gorilla Grips, it's my understanding that they can't use that tool at narrow seams like you'd have in the middle of a sink.

Here's how they did my seam, perpendicular to my sink.

But yeah, as Joe posted, it's more about size of slabs and lay-out.

lisa_a:

The latest incantation of the Gorilla Grips allow clamping on smaller areas. The alternative is to stick the Gorilla's to each side of the sink opening and clamp a bar clamp between them.

I'm loving the seam at the middle of the sink. I'm a convert. My GC suggested it and my fabricator said they do it all the time. It's very effective when you have a busy pattern. It reduces the problem with matching patterns. Here's a picture of mine. I can see it if I really look. That's only because I'm looking for it an I know it's there.