We have tried to find someone to design the layout/exterior but the architects we have consulted want to be a part of build from start to finish

That sounds more like a builder or design/build than an Architect.

Are you talking with someone licensed as an Architect?

Ok, we are not sure which expert is required, only that we desire plans but this is all we are needing. How do we go about finding someone to draw up the design plans?

A talented designer (Architect or not), is who you need.

There is a Find A Professional link at the top of this page. Seek someone in your area.

Review their work, fees etc prior to signing a contract.

Make sure you get someone who can design, not just draft up a set of plans.

I'm confused. Do I understand that you have one room built, but no foundation for the rest of the house, and no clear idea of where that foundation will go? Or is it that you have a foundation but are not sure about the interior layout?

You’re a little late. A phased build isn’t designed in phases. Only built in phases. The whole house should have already been designed, and only the master built. What you are describing is a heck of a lot harder, because you’ve already tied your hands on the front end with some decisions that may not work at all with the bigger idea of a home instead of a unabomber cabin.

You are really describing a truly ambitious remodel. Not a new build. And that may be some of the disconnect that you are getting from the design professionals. It’s not a new build when a structure severely limits what can be designed. In fact, the cost of the project just went up to have to deal with that restriction. You may find that it’s cheaper to bulldoze it and start over. But, it’s a remodel, not a new build. Similar skill sets for the design pro needed. But a different outlook and budget.

I am totally confused as to what the heck you are doing. You don’t start a house from a bedroom already cinstructed. IMO you need an architect and you should have someone involved in this from the get go.

The way I read it, the structure is already on the property and they want take advantage to incorporate it into the new home. I suggest getting someone out to the site to evaluate the structure to make sure that's a good approach. The structure of a building is a smaller portion of the cost of the building than most people realize. You can easily spend a lot more than a structure is worth by trying to save it.

". . . the architects we have consulted want to be a part of build from start to finish . . . "

Having a local architect involved in the whole process may be to your advantage.

Lol. Trying not to laugh at some of the comments. So we built a 24 x 16 cabin thinking this would be our great room and that the next phase was bedroom and bath. We decided that this space is not sufficient for our needs so we are making the existing space the master and the next phase is much more ambitious with mudroom/laundry/bath and the great room. We intend to add on and it doesnt have to be that complicated. This is probably why we will just do the plans ourselves.

"...This is probably why we will just do the plans ourselves..."

Good luck! Let us know how it goes, and if it wasn't "that complicated".

will be doing an owner/build exemption.

I don't know what this means.

We have what will become, our master bedroom, already built ... We know essentially what size we want BUT we dont know best layout for everything nor the roof lines and so forth ... We don't have design software experience ... couldn't find any for 24x32 floor plan ...

Okay, I think this was a very complicated way of saying, "We have a small building and want to add onto it. This is a renovation /an expansion."

What you are describing is a heck of a lot harder

So much harder, but you have what you have.

I assume this is an older house that was already on the property? Is it in good condition? What kind of foundation does it have?

I wonder if you might do better to use this as a storage building ... and "start fresh" elsewhere on your 12 acres.

So we built a 24 x 16 cabin thinking this would be our great room

Oh, you walked into this on purpose! I'm wrong about this being an old house. Was the cabinet permitted?

How is 24x16 not an ample great room?

We intend to add on and it doesnt have to be that complicated. This is probably why we will just do the plans ourselves.

I think you need some help with the plans.

Why? You've already put money/effort into one space, which you've now determined isn't what you need. You have a gauge on the sizes you want (even though you missed on your first try with the great room) ... but you don't know where to place the rooms. This seems like a backwards way of addressing the design.

Step back and ask yourself, what would you say to someone who told you what you just told us?

OP - if you want meaningful help, post a plan (with measurements) of what you already have built, with windows, doors and plumbing, plus where north is, and the existing elevation. That's the bare minimum starting point for anyone, yourself included, to begin planning you extension.