Roof overhang also provides protection, which isn't taken into account in any of your shapes.

I'm surprised to find #7 if you're presenting serious considerations, since it will collect water and debris and the V's will be most difficult to maintain and keep water tight over time...Probably the most difficult to construct adequately. Worse than a flat roof, IMO.

The shed roofs (slanting only 1 way), leave one side of the house more exposed to elements as well as giving the interior one very tall side and one very short side. I'm not sure that's the maximum gain in 'livability.'

The 'conventional' shapes became that way because of their combined advantages in protection and what they offer in interior space.

I have no idea if I'm giving you what you're asking for...

You should consider the cost and style of framing or trusses for each too. Also the slope required for each format. A higher slope means more expensive to install as it is easier to slip and thus costlier. A too low slope rules out several materials. Rule of thumb min 4:12 for shingles, 1:12 for metal, (there are exceptions to everything so just a general rule of thumb) and max 6:12 for most roof types if you want to save on the cost of installation due to steeper slopes. Also need to consider material for the roof and how each material would work for the different styles, flashings etc. required for valleys and transitions between different slopes. Complicated transitions in slopes and any valley or change in slope is often a point where you are more vulnerable to water intrusion.

Another thing to consider is attic ventilation. Ridgevents and undereaves vents only seem possible in a couple of your designs. In others you could do undereave and turbines or other vent type sitting on the roof.

And in Florida using all hips will get you an insurance discount.

I'm glad you're moving away from the flat roof idea. At around the time you posted your original question, someone had a thread going on about a modern interpretation of the barn (as a house). They were very sleek and modern and perhaps suited to you, if you could find that thread.

I don't believe they were "gambrel" roofed barns, so would be closest to your "number one" design. Barns are certainly efficient shapes, very time tested.

Be sure to pick a design that works with conventional construction techniques and materials, or costs will run up.

Thanks for the responses... they raise a few more questions for me:

What is the functional purpose of an attic? Why not build the interior ceilings right up to the roof?

Is there a slope "rule of thumb" for shedding snow?

"Why not build the interior ceilings right up to the roof?"

These would be cathedral ceilings, which are done often...But they require more sheetrock and finishing for higher walls and angled ceiling, more structure showing inside, no use of trusses, which are light and easily and affordably obtained premade and engineered for load, and it's easier and more economical to insulate the house adequately. Also, they're not too energy or comfort friendly, since heat rises and you pay to heat the extra space while you may still be chilly down below.

The classic attic, from using rafters instead of trusses, were economical, unfinished storage space, although could vary greatly in temperature throughout the year.

I'm the wife and daughter of men knowledgeable in building and am speaking from what *I think* I know, so someone more knowledgeable can feel free to correct any misconceptions I've communicated here.

If you really want to fry your brain, do some searching on dome homes, which supposedly (in their opinion) are the most efficient shape.
If there were a risk of high winds, a hip roof is best. Otherwise, a plain old gable roof is my preference for simplicity, and the attic is a handy place for utilities in the absence of a basement. To me, aesthetics also plays a big role, so I wouldn't consider some of the stranger options.

OK, I see you are building in Connecticut. You DO need to consider snow load, if only for the freak storm that dumps a lot of wet snow. (When I saw the concave roof design I thought you might be building somewhere where you wanted to collect water in a cistern on the roof.)

Overhangs ARE good things. They keep the sun from frying your interiors -- and you. They let you open casement windows, sliders or french doors while it's raining -- without soaking the floor. They keep water from soaking the tops of your walls.

You'll probably want gutters and downspouts to chanel water away from doorways and keep rain from cutting a trench in the dirt all around the house. The single plane roof could work, with guttering only along the low edge; you could collect water into a cistern on that side.

There's been some talk of trusses for attics. In our build it turned out that framing was only slightly more than using trusses -- and it resulted in a full-height useable storage space. With the addition of some dormers, it can become additional BRs and baths.

"These would be cathedral ceilings, which are done often...But they require more sheetrock and finishing for higher walls and angled ceiling, more structure showing inside, no use of trusses, which are light and easily and affordably"

Rhome, you can have cathedral ceilings with trusses. I designed my own home and wanted a vaulted ceiling. I also wanted trusses so there would be no load bearing walls on the inside of the house, which made the design work easier and did not require an engineer. The trusses are called scissor trusses. The ceiling of the house is not open all the way to the bottom of the roof...there is a space inbetween, but I have a nice vaulted ceiling now.

Also, I like a pitched roof and the use of what is called "attic trusses". Again...no load bearing walls are needed under them and I have a 12' wide room above my garage and master bedroom. The ceilings in those attic rooms are 7' 6". To gain this space, I raised the pitch of my roof from the originally planned 6/12 to a 9/12 and ordered attic trusses instead of regular trusses. For not much extra money, I gained 480 extra sq. footage. The space over the garage will be storage and my hobby room will be over the master bedroom.

ccoombs, I know about scissor trusses for a bit lower cathedral ceilings, but those didn't fit ooopie's question about having ceilings right up against the roof. :-)

If you want the look of a cube, what about having a modestly slope roof, but with a parapet that hides it? I may not be using the right term, but what my parents have is a "flat" roof that's not really--it's sloped, but on one side the roof itself comes up to the top of the wall. On the other side, the roof hits the wall about 2 feet down. From the exterior it looks squared off. Functionally, however, there is slope to allow water to drain effectively.

As for snow, they've been worried for 30 years, but they have not had the roof collapse despite the many wet snows they get just outside of Boston.

I've been mulling over this stuff for a few days, and I'm really drawn to a particular style with a single slope, sometimes called a "shed roof"

It has advantages that other styles just don't.
It's simple, adapts perfectly to passive solar design, and is unique. I explain it more in the blog. What do you all think?

Here is a link that might be useful: http://theopenhouseproject.blogspot.com/

I mean no disrespect by saying this so please don't take it that way:

Instead of trying to re-invent the wheel, I suggest that you do what I did. Research (as in google certain keywords and read, read, read) the information that is already out there (and in use) for the various aspects of building that are important to you. For you, I guess that would begin with passive solar, energy effeciency, snow country, minimum waste, etc. Then, once you learn about what is done in the different situations and why, take a look at what the different designs have in common or where they are slightly similar. Armed with that understanding and knowledge, then begin to design your home that incorporates the design stragies that would give you the results that you want.

It seems to me that you are trying to figure out building science aspects that are already known and documented. Instead of trying to reinvent it yourself by brainstorming, I think you would be better served to put that time and energy into reading what is already known.

I hope that my suggestion helps you. Good luck with your project.

Yeah, I've been doing lots of research and it's wonderful how much used brain power is freely available for the taking. All of my ideas are greatly inspired by things I've read.

This is just my way of piecing together the cognitive collage, and granulating each element for analysis, in this case the roof style.

Here is a link that might be useful: http://theopenhouseproject.blogspot.com

I built a semi-custom house in northwest connecticut in 1985. i chose a lot that was half-way down a south-facing hill/slope, as that gave me access to the sun and protection from north winds. i modified a stock plan so as to achieve an efficient passive solar house. i chose a salt-box style roof, with the long side on the North, and i extended the south side to create almost 3 feet of overhang for shade in the summer. this gave me the advantages of the sloping roof that you cite, but also gave some others: the salt-box style was more in keeping with a traditional New England look; it provided higher ceiling height for the rooms on the North side of the house; and the overhang was much more efficiently placed vis-a-vis the south-facing windows than it would have been with a simple sloping roof.
the house was amazingly cheap to heat.