We are a family of 8, with 6 kids ages 9 months to 17. We've lived in
our home for 12 years and are looking to renovate. Ideally, I would
like to open up the layout and make the space more open and usable by
more than one person (particularly prep/cooking while another person is
cleaning). We never entertain on our main level, instead having to use
the basement. Our basement works well for that, but I would like the
option of entertaining upstairs, especially since we are currently
converting our covered deck into a four seasons room.

Dependent
upon cost, I would like to add on a mudroom/pantry from our garage. We
have an extra deep 3 car garage and and 7'x11' room would only take from
the extra space, not a stall. We are also planning a new garage on the
other side of our property, so space isn't a problem.

I would like
to have an island or peninsula if that can be worked out. We are
keeping our current appliances - only 2 years old and love the slate! I
would like to do as much work ourselves as possible, contracting out
only where it makes the most sense. Electrical is not a problem to move.
I would prefer plumbing changes to be minor if possible.
Thanks for any help!

I don't think you'll have space for an island, but here are two quick plans--one with a mobile cart, and one with a peninsula. I extended the mudroom in both plans, to give you a longer wall. With 6 kids I'd keep the mudroom for lockers, coats, boots, etc. and put a step in pantry (plan on the left), between the kitchen and DR. If you use part of the mudroom as pantry space, and move the fridge to the space between the kitchen and DR, you'd have space for a peninsula, but with 6 kids, how do decide who gets to sit at the peninsula? ;)

Maybe someone else will have a better idea. Good luck!

Why do you entertain in the basement? Is it a walk out? Just wonder what the basement has that the main level doesn't so we can try to get it for you.

Do you need to keep the formal dining and living?

mama goose - Thanks for the input. I definitely prefer the peninsula to the cart. It's an awkward space to work with! I'm not sure we'll be able to make the mud room larger. We'll have to tape out in the garage to see just how big we can go and still fit a car in the stall in front of it.

benjesbride - Yes, the basement is a walkout. The main room down there extends the length of the house and has a living area, dining area, pool/ping pong table (which doubles as a large serving area for parties) and a kitchenette. It handles a large amount of people easily.

I definitely want to keep the formal living and dining. We prefer the somewhat closed off nature of those two rooms.

Keeping the mudroom area as originally drawn, except moving the door down as far as possible, would look something like this, but the sink and range would both be up against corners, with the prep zone under the window. You'd need to make the sure there is sufficient filler in the corners, so that all drawers and the range door will open without hitting handles.

Here's another idea if you can move plumbing and shorten the wall b/w the kitchen and the FR.

For the peninsula, I'm thinking cabs facing the sunroom/FR. If you can fit your mostly used plates/glasses in those cabs, then 2 can prep on the L counter and others can load/unload the DW or set the/clear the table.

I wonder if your family would be served well by a counter and cabinets where the current nook is located. This would be great for laying out buffets, as it's right on the way to the 4 season room. Drawers below and cabinets above would give you a lot of storage. It would be a nice spot for a hidden printer, office supplies, household goods, etc. if the space was not needed for the kitchen proper.

Does the door to the pantry/mudroom have to go exactly where you have it drawn in? I think I'd try playing around with sliding the pantry door up to 2' below the top wall where the sink run is located, so that you could have a straight run of cabinets all the way along the sink wall rather than trying to make the cabinets turn the corner. (Corners are sometimes space wasters.)

Here is a rough sketch. It doesn't get you an island, but it does get you lots of prep space by the stove, with its own prep sink. A secondary prep space can be combined with the separated cleanup zone, which can be nice for big, busy households. If nothing else, maybe this can help get the creative juices flowing. : )

One more thought: Would it be helpful to flip the basement stairs around so that you enter the stairwell from the family room-front entryway area? This would allow you to tuck the fridge in the old basement opening in the kitchen. Then, you could have a 5' long peninsula tucked against the wall of the stairwell, where I drew in the fridge, above. It's not an "island," but it comes awfully close to one. ; ) Of course, if there is a stacked set of stairs to an upper floor, this idea dies a quick death.