My wife and I own about 1/2 acre in Central OH and we are currently in the process of clearing it to make it ready to build.  (Unfortunately building wont actually happen for some time due to financial crap).

We have a few questions and are looking for ideas or suggestions.

1) We are looking to design our own home as the building requirements for the area have some issues we have to meet (Garage needs to be a rear entry and need a minimum of 1400' on the main level, the area we can build is 72' wide x 100' deep and we could build anywhere in that area.) Because of these, we are wondering about how much can we expect a designer/engineer to charge to basically take our floor plan and convert it into what we need in order to build?

2) One Idea we had was to do a 2 story home, Master Suite, Guest Suite, Living Room, Kitchen, Dining room and Mudroom/laundry on the main level with the bedrooms split and a tall vaulted Living Room.  For the second level we were just planning on 2 Bedrooms, a full bath and a loft.  Would we be better off (cost and ease of building) to just make the whole structure the same 2 story height (with a lot of empty/wasted height), or to make the Living Room Vaulted and then make the area over the second master suite a single story height? (then how would we build that exterior wall that is in the middle of the structure without losing a lot of the benefits of ICF?)

Any help would be greatly appreciated and I am sure I will have more questions as the process progresses.  I will be glad to answer any questions and when we finally get going, I will of course give updates.

design is your choice and preference the middle wall or walls can be constructed just the same as exterior walls in ICF -most ICF form makers do "t" sections to join ,but in not then fit in re bar and wood braces to formers at corners where you meet outside walls and cut out section to make your own T joints. but if its not going to be load bearing why make from ICF? use stud walls or sip panels ,whatever .In uk vaulted ceilings are usually used to fit a large atrium window in the gable end so you get lots of passive heating of a tiled floor from sun ,hope you like cleaning cobwebs from ladders if you go for a high vaulted ceiling .LOL
you mention costs --maybe price of long span beams etc could offset by more internal walls and shorter beams ? so make your design and then cost it first --maybe a little rejig could save you money
you mention wasted space upstairs --if roof is sip panel type then you can make a nice upper room with what we call "combed ceiling --walls at edge of room not full height --maybe 5Ft then inside of roof if insulated well it isthe rest of the ceiling at same angle as your roof --basically a 1.5 or 2.5 storey house with dormer windows in top level
all up to your design

Talk with an engineer and architect about how you WANT to build the house.

Now, a simple two-story "box" would probably be easier to engineer.
And the extra interior space wouldn't be "wasted" per-se.

However, there's nothing stopping you from pouring the first level, then pouring only what you need for the second level.

As for Scottishjohn's "why not use different materials for the other parts", I always loath trying to mate up two separate construction types. Mainly because air-sealing the interface is a gigantic female dog.

What I would do is take your basic plans and floor plan (plus code requirements) to an architect.
Specify that you want to build in ICF (if you have a preferred vendor, specify them). and have him make a first pass at it.

Also, are you going to be doing this off a slab foundation? Or are you going to have a basement/crawl-space?

Posted By Dilettante on 26 Sep 2018 08:16 PM
Talk with an engineer and architect about how you WANT to build the house.

Now, a simple two-story "box" would probably be easier to engineer.
And the extra interior space wouldn't be "wasted" per-se.

However, there's nothing stopping you from pouring the first level, then pouring only what you need for the second level.

As for Scottishjohn's "why not use different materials for the other parts", I always loath trying to mate up two separate construction types. Mainly because air-sealing the interface is a gigantic female dog.

What I would do is take your basic plans and floor plan (plus code requirements) to an architect.
Specify that you want to build in ICF (if you have a preferred vendor, specify them). and have him make a first pass at it.

Also, are you going to be doing this off a slab foundation? Or are you going to have a basement/crawl-space?

not planning on a simple box, per se

The stucture will be over a full basement.

But to try and come up with a different explanation for what I am talking about, think of having 3 boxes (2 the same size and the 3rd smaller).  Stack them all on top of eachother, and the 3rd smaller box shares the front, back and one side wall with the two below it.  What recommendations would people make for that fourth wall to get the best cost effective compromise?  Or would it be best to just make all of the boxes the same size?

design first --then you can get best solution for actual building it--pretty sure ICF can make any shape you can think of with correct design

So basically something like

_____________
[ ___________]______________ 2nd Floor
[ _________________________] 1st Floor
[ _________________________] Basement

There should be nothing stopping you from doing this with ICF. I'm taking it that you're going to go ICF for the basement as well?
Yes, it would be, STRUCTURALLY, simpler to make all the boxes the same size, as all you really have to do is make sure your concrete is of appropriate strength, proper pour and properly leveled and plumb. But you don't HAVE to.
Essentially what you're doing there is trading simplicity of design for 10-15% increase in materials cost and the need to finish that part of the structure.

Just talk with your engineer/architect about how you're transferring the load of that one exterior wall to the interior structure and down to the ground.
But pre-planning load points on the two lower levels isn't rocket science.

Posted By Dilettante on 27 Sep 2018 10:33 PM

So basically something like

_____________
[ ___________]______________ 2nd Floor
[ _________________________] 1st Floor
[ _________________________] Basement

There should be nothing stopping you from doing this with ICF. I'm taking it that you're going to go ICF for the basement as well?
Yes, it would be, STRUCTURALLY, simpler to make all the boxes the same size, as all you really have to do is make sure your concrete is of appropriate strength, proper pour and properly leveled and plumb. But you don't HAVE to.
Essentially what you're doing there is trading simplicity of design for 10-15% increase in materials cost and the need to finish that part of the structure.

Just talk with your engineer/architect about how you're transferring the load of that one exterior wall to the interior structure and down to the ground.
But pre-planning load points on the two lower levels isn't rocket science.

That's exactly what I am trying to get across. The big concerns would be the load transfer from the unsupported exterior wall on the 2nd story and what that wall would be made from? (Would it cause me to lose a lot of thw efficiency benefit of ICF?)

bottom line is that it would be simpler and better for thermal results to make top level in SIPS+sips roof panels,but as has been siad --design it first with a professional then decide what to systems to use.just my 10cents worth

I'm going to differ with Scottishjohn.

You're going to have to engineer point and span loads on the unsupported wall REGARDLESS. You can't simply free-span it. Even with SIPs.
There will need to be some form of supporting structure going through the lower floors and into the foundations.

Again, talk to an architect and an engineer with your plans in-hand. They'll be able to give you the advice you need.