curious why do you want such a large house? Family? Entertaing? Rural area? etc
You also have to factor in taxes, insurance and does it match others in the area.--that is, are the other homes equal or ?? to the one you want to build

I dont really understand your sqft question. So you want 8000 TOTAL with a walkout (4k each floor) or do you want 8k total each floor (14000 sqft). Either way, way oversized, but hey, its your money!
Basements vs full 2nd stories are typically cheaper, depending on your foundation type. If you have a very low frost line, or none at all, then slab on grades are cheap. Around here we have a 4' front line, so its basically nearly the same price to do a full basement, costing a fraction of what a full 2nd story would be.

7000 to 8000 sq feet is WAY out of my league. Don't know if I've ever even been in a home that size - well, except for touring the Palace at Versaille once. LOL!

I think Worthy often designs and builds houses in that size range tho. Hopefully he'll chime in with his real life experience.

If not, you might try seeing if this online cost estimator can give you any guidance I'm not saying it'll give you "accurate" answers for any of your options, but it might give you some idea about how varying the number of floors you're building, while keeping all other things constant affects the prices it predicts. (e.g., one option turns out to be 20% more or less than another)

Here is a link that might be useful: online residential construction cost estimator

I was really wanting a 4000sq foot main floor with a 3000 sq foot basement or 2nd story. Is 7000 combined really that big? I have a gf with 2 kids(that i love) but not sure if that will work out forever. But my ending plans would be a wife with 2-4 children.So i wanted a big great room and a nice kitchen. A pretty big playroom for the babies as they grow that can be turned into something else when they grow up. I need an exercise room and wanted a home theater room. 1 big master suite and about 4 decently sized other bedrooms for the kids as they grow as well. I pretty much just want a lot of space to get creative with and be able to hang out for those 20 years of rasing kids and some occasional family gtherings. Also i cant really think of an cool custom features to put in a house for kids and adults alike, any ideas would be appreciated as well

We have 5000 sq. feet between the first and second floor, plus a 3000 square foot basement that we are planning to finish some day so about the size you are looking at but spread across three floors. Our house is nice sized but it doesn't feel *too big* because other than a big great room and a big kitchen, we opted for more smaller rooms instead of huge ones (small being relative).

I think whether or not building up or building down is most cost effective for you is going to depend on your lot. If your lot lends itself to a walk-out basement, it might be cheaper to do it that way. But, I believe (and I could be wrong) that anything below - grade isn't valued as highly for the appraisal so even if you create an amazing finished basement, it might not appraise for what you need it to to get a mortgage (if you are getting one)

Other than that, the main things that are going to affect your cost are roof lines and interior finishes, not so much whether you have a walk-out basement or not. If you build a rectangle, it is always going to cost less then a bunch of ins, outs and peaks or god forbid circles and arches. Same w/ if you put a bunch of expensive stuff (flooring, trimwork, LED lights, etc) in, regardless of whether you put that expensive stuff on a basement or a second floor.

Beagle do you have a daylight walkout basement or a walkout basement. I was thinking about a normal walkout because of not having the slope possibly for the daylight. Also when you have to grade the land for the daylight walkout doesnt it usually leave a small backyard that is level with the walkout but all land around sloping back up to normal level.

I don't know what the difference is between a daylight walk out basement and a regular walk-out basement. Our walk out basement is to the side of our house because of the way our lot is arranged (to say our lot was difficult and expensive to work with would be an understatement, but it couldn't be passed up b/c of the views, privacy and neighborhood).

Our basement doesn't affect our back yard at all. It's probably not going to have the prettiest view to the front, but it makes the basement plenty light. Oddly, I don't have any really good under construction pictures showing that side of the house for some reason, but this picture shows how it works:

And here is an old one before we got doors!

A walkout basement is.....well a walkout. The house is built on a hill. A daylight basement is when the basement has windows up higher letting in light, but no door to outside. Built on a flat lot.

do you always have to have a deck with a daylight basement since the main isnt completely level with the lot

We have a daylight walkout basement, 1600 sq ft, 1800 first floor and 2200 second floor for 5600.
Basements are usually considered cheap finishing space because the walls were framed "for free" to do the foundation. That doesn't apply in the south, only the north.

But, as long as the stairs are not absurdly ornate or complicated, using 3 floors (basement, first and second) to split sq footage equally should be the most cost efficient building. If you need 8000 sq ft, look for a plan with 3000 second, 2500 main and 2500 basement. make sure that the space over the garage is used on the second floor (which is why the second is 500 sq ft more than the first). No curved walls, few angles other than 90, and as few corners as possible.

That sounds like a pretty good idea charlotte. Would i be able to do something like a 3500 main level with a 3000-3500 second level and 1000 sq foot comeplete underground basement with window wells so that the main floor can be level with the flat lot

The downside to doing that plan and making the upstairs have more square footage than the down is that you lose the opportunity for double height rooms and dramatic ceilings. Some people don't want those because they think they are a waste of space and hard to heat/cool. I think they make a house, and as such, our main floor has more square footage than our upstairs and there are no upstairs rooms over the foyer, great room, conservatory, sunroom, or master bedroom. Our square footage is more like 3000 sq. ft. basement, 3200 sq. ft. main level and 2300 square foot upper, with only 3 large bedrooms and an upstairs laundry room on the second floor.

Our house is also not costing multi-millions to build and we have very high end finishes and trim, hardwood flooring and built-ins everywhere (we skimped on nothing) and we have 5 acres overlooking a pond, high on a hill. A lot depends on where you live, as far as what it's going to cost you in an idyllic neighborhood w/ only 16 houses and 244 acres of trails and woodlands for public use.

Our house is similar in size to beagles. Our basement is huge and we didn't plan on finishing it as we have slightly over 5000k on the first two floors. This includes a HUGE playroom over our 3 car garage (not the whole garage but it includes the two dormers for daylight - the rest is walk in storage).

We too have smaller rooms - really none are much bigger than our current 2800 square foot house except the kitchen and dining room. The dining room was driven by the fact we have a 10' table and I wanted to be able to use the entire length of it for family gatherings. The kitchen is bigger because ours is tiny, but it is really not huge. The square footage difference for us is really an extra bedroom upstairs (which we wanted because we have 3 kids and frequent guests), each bedroom has its own bath (not big ones for the kids, but ensuite), and each bedroom has walk in closets of some sort (we have them now and couldn't give them up even for the kids because of all the toy storage).

Where our house is actually bigger though is in the utility space. We have a much bigger laundry room with storage closets for cleaning supplies, room for a freezer, room for separate laundry baskets for each boy (so they can put away their laundry, etc.), a small pocket office for me (35 square feet) where I will pay and file bills, keep my shredder, etc., a small locker/mudroom for backpacks, jackets, etc. and what I call the mud bath (we also have a powder room next to the den for entertaining). This is for Moms covered in dirt from gardening and boys filthy from traipsing through the woods. We also have a staircase in our back hall (which takes up a lot of square footage), planning for teenagers coming in packs and wanting to let them in through the friends entrance and straight up or down to the playroom or basement.

As far as high ceilings go, that is a personal preference. I specifically requested no ceiling higher than 10' and that is what we ended up with. We are going for a house built in the 1920s or so and fluffed through the years - so a new/old house. Vaults weren't around then so we didn't want them.

As far as cost goes, you are likely in the 7 figures with a house that size, mostly on one level. Second floors are cheaper to build than single story. Our first floor is 2600 square feet, less upstairs. The basement is the size of the first floor but we are not finishing all of it (although we framed it). It has a seperate guest bed/bath wing which we may or may not finish down the road. It would be a perfect au pair suite for the next owner or an inlaw suite, or a kid come back to live at home suite. Hopefully we will not need either of those!

The thing to realize about a walkout basement, which we have, is that you have to either have no deck/porch area or you get into lots of money. I didn't want a deck so we ended up with a stone patio, raised to the second level and requiring a lot of steel and concrete. This has created a wonderful space on the basement level (much better than a deck would have), but it was extremely expensive and had we known what it would have cost we may have made different choices!

This is what i have so far, the main level might need some fixing but im liking the 2nd level, its a dedicated bedroom level pretty much at this point. You can look around the great room from the 2nd floor hallway that goes around 3 sides. 1st floor is 3000sq feet and 2nd floor is around 2400.

http://www.homestyler.com/designprofile/53fa3080-c89b-4364-aee9-fae18f34d267

it4-
you are getting way to far ahead of yourself. Most people will start to consider sqft numbers as a extremely rough prelim budget. First think of how much you have to spend. construction costs are anywhere from $100-350+ per sqft depending on location, finish quality, etc. 200 will typically get a lot of things people want, so lets assume that number. So 200 x7000 puts you at around $1.4 mill plus land and development. So think about that first.
Next thing you need to do instead of thinking you want a certain amount of sqft, develop a program and write down all of your needs and wants. Let the house become what it NEEDS to be, instead of starting with an empty box. Form follows function. You may find you can get everything you need for only 5000 sqft. Thats a $400,000 savings!
You have no idea on correct room sizing until you start to layout the use. The layout of the kitchen will greatly affect how big it is. Bedrooms are another. Do they need just beds and closets or also dressers and desk space?

If you are REALLY serious about a new home, especially one of this magnitude, do the research. Start by reading up on everything home construction. The more research and education you can give yourself will only help you in the process. Look online for inspiration. Figure out what you need first. Become organized. Then take your thoughts and ideas to a good architect. Let them work up a plan for you based on your needs.

As others have mentioned, the cheapest is spreading the square footage as evenly as possible over 2 stories and a basement.

But, aren't you going about this a little backwards? Instead of having a fixed square footage number at the start, I would start designing a space to meet your needs and see what square footage number you come up with.

Some of the spaces you describe- home theatre and exercise would ideally be in the basement.

Other things you need to decide is do you want the master on the main level? And do you reall want to finish all 8000 square feet now? Or leave potentional to grow as needed? We've finished about 5000 square footage but have the potentional to add 2K more if needed. But honestly the 5K feels huge and too big to me, so I can't image ever finishing more.

As far as a walk out vs daylight. We chooose daylight which is unusual in our area. But I wanted the main level to be level with the ground so that we can have a large patio. I didn't want the yard divided in half by a retaining wall to accomadate a walk out. It's a matter of personal preference.

Thanks for all the advice. To pps7 how do you have 2k potential to be added, do you have unfinished areas or can you just add on to current structure is what you mean

Bevangel -- Thanks for the costing sheet. Good lord! I ran our house. To build it now would cost twice what it cost in 2001.

Zillow tells me I can sell (house AND lot) today for $200,000 more than just the LOT cost in 2000.

"Bevangel -- Thanks for the costing sheet. Good lord! I ran our house. To build it now would cost twice what it cost in 2001. "

I ran my house too... with what is here now.

I am SHOCKED that it came out to $518,741.00! For that price, I can get MUCH fancier/custom and WAY more land. MY house will sell for half that, and we paid way less.

I have to give that cost estimator some praise.

While certain line items were way off, the overall # was within 5% of a real estimate. Some items were 70% off but there were an equal number over and an equal lower.

But - we are building oceanfront and the locale was just a fairly close but non coastal city. So I'd expect building inland, it would have overestimated costs by 15-20%. In this case it was pretty close but overall I think it estimates a bit high.

Insulation for a square 2100 sqft house in a very temperate zone at $4500 - that is way high. The HVAC was also higher than 2 seer 15 heat pumps by about 20%.

luan -- Remember, the estimate is only for the building, not the lot.

Our lot cost more than our build. We wanted a one-floor retirement home *in a prime location*. Builders who also did teardowns here built to the zoning max of 6000 sq ft/acre and made money. The last guy overreached, got caught in the bust, and didn't break even. Started at $7M; sold three years later for half; value now is probably even less!

"luan -- Remember, the estimate is only for the building, not the lot. "

That makes it even worse then! LOL!

I guess the formula can't work everywhere....