Can you reach the plumbing from below?

I guess I forgot to mention this, but nope, we're on a solid slab, so the cement will need to be cut open, the plumbing and electrical lines extended and then refilled and re-floored.

You can ask on the plumbing forum, but I think that will be both costly and messy. Cutting into concrete to install drainage as well as a vent stack, water and electrical, repour concrete and recover. Anything can be done with enough money, time and patience, but this would be more than I would consider.

YMMV.

If you're on a slab then its a lot of work. If you're not on a slab then its very doable with average plumbing skills and some research. The cost is mostly labor.

As for the electrical, thats easy if you can find a source to safely tap into.

Now you don't have to have a prep sink, a lot of people live without one and don't miss it but you have to have an electrical outlet in the island by code plus it comes in handy.

I just did the same thing DIY for my kichen but I planned on ripping out my 1960 oak floor.

I did it. That is, I had it done. It's a very, very big job, and most important, you have to get the fall line on the drains right, as well as the venting. I wouldn't recommend doing it DIY without a lot of plumbing experience.

You can see my experiences with it on the linked page.

Oh. I don't remember if it's on that part of the blog, but the first thing the GC did, well before demolition, was sent a pipe camera down into the plumbing to see exactly where the drains were and to measure the fall line to make sure putting in the island would work.

Going to the center of the X of trenches from the wall with the poppy (where the old sink was) are water, drain, plumbing vent, electrical, telephone and cable for the island. The two spokes of the X take a cold water line to the new freezer (ice maker), and full plumbing to the site of the new steam oven. The final leg of the X goes to the drain and vent in the laundry.

You might not need all those trenches, but the main one to the island, with the drain and vent out, was the tricky one.

Yeah, I pretty much figured it would be a big job. DH can sometimes think way overboard and I was pretty certain this would be out of the scope of what we're able to do or are willing to pay to have done.

Thanks for weighing.

Kathe

I'm pretty sure that you're going to need electrical on the island to meet code. I'm not sure what the minimum size is that triggers the requirement but a 6' x 2' would qualify IIRC.

May I ask where your refrigerator is? Will you be creating a "barrier island"? I.e., An island (in your case a long island) that is b/w the sink and range, b/w the sink & refrigerator, or b/w the range & refrigerator.

If it's a barrier island b/w sink & refrigerator or sink & range, then a prep sink can be very important to keep your kitchen functional.

How wide will your aisles be b/w the island and sink/range/cabs or appliances on each side?

BTW: my friend added an island using cabinets and a butcher block top. It is on casters so they can move it around as necessary. Since it is a 'table', code does not require an outlet. I think it's 6'x4', but it could be a bit larger.