I am interested in this, too. I found an older GW thread on this earlier today, but would love to see more recent info from people currently building. I'd also like to know if special structural work has to be done to the walls to handle all the openings.

It is important to specify single or double pane glass, coatings and if they will be operable.

The structural issue is providing adequate lateral bracing to resist wind and seismic forces. An entirely glass house might require a welded steel frame.

It's impossible to say how much this type of glazing will cost because it depends on the design of the house and all of the considerations Sanford just described. But if the view, the concept of "inside-outside" and/or the desire for maximum indoor lighting are a factor, then these can't be achieved without extensive glazing in the right places. In such situations, this type of glazing becomes the priority and much of the rest of the design of the house revolves around it. Design is all about priorities and what's most important!

Not sure of the cost of large windows, but in addition to the cost of the actual window, don't forget to plan for the cost of window coverings for such large windows -- depending on what you want, the window treatments can cost more than the windows by quite a bit -- I have lots of large windows in my home (the architect took me at my word when I said I wanted lots of light!); while I specifically chose not to cover the windows in the main living areas (and I do love, love the windows), the potential cost of window treatments for bedrooms and bathrooms was huge. I had to dial down my first plan of custom fabric, motorized roman shades ($10K+ for the bedroom) to something a bit more modest.

Yes, I guess the question I should be asking is, what's
the overall cost of a wing built with conventional windows vs.
one designed to have one wall, say, that's mostly glass.
It seems to me that there are two major issues:
1. the difference in cost between the structures
2. that the windows for the glass wall will probably have to be
custom-manufactured.
If I had even just a ball-park guesstimate of the cost ratio between
conventional and wall-of-glass approaches, it would help in working
with an architect who is not experienced in modernist concepts.

Triple the cost between conventional framing and welded steel framing. Then the glazing will be more than triple as well to fit within that framing. So, take a typical 150K master wing addition and it would start at 450K. Could be more with seismic or high wind engineering, or in a cold climate. In a cold climate, you could not possible achieve the needed insulation levels with such a design, and you'd be burning money by the bushel for heating. Same with a hot climate and AC needs. That type of design has specific climate parameters in which it's actually practical. But, only if you have a healthy budget.

What Sophie said, (big pieces of glass equal BIG $$$$).

Agree with last two comments. In fact meeting with architect and builder today to talk downsizing or completely eliminating some windows today. Windows cost $$$ and then the treatments on them add more $$$. My thoughts, put in huge windows and then cover them up? Why?

We have a new house with very modern design and lots of windows. But not the wall of windows that open like that picture, because the house is in a cold climate where those would let in cold and just wouldn't be usable enough of the time. But we do have lots of large windows that go up to the roofline. And probably every window in the house is a custom size.

Our architect is experienced in modern design; in fact, that's why we chose him. And when it came time to selecting a builder, he gave us a list of three who he knew had built modern homes, and knew how to build that type of construction. I would be wary of working with an architect (or builder) who isn't knowledgeable about these techniques.

Window treatments. Our house does not get a huge amount of natural light, so we don't have to worry about too much sun. The only rooms with blinds are the bedrooms, exercise room and one bathroom. Exercise room is ground-level at the front of the house; I would be self-conscious working out where everyone walking/driving by could see me. We don't have any window treatments other than the blinds.

I disagree that they are as expensive as some people are saying. I have looked into walls that open like lacantina and they are expensive but not crazy. I think it would be best to take examples or your plan into a window place near you and see what they say.

Fixed glass is not expensive. For large expanses of glass meeting the building code requirements for lateral bracing and energy conservation can be very expensive. Therefore, the first consideration is where the project will be located.

Well I agree to some extent but I estimate glass everyday and depending on the size fixed glass can get VERY expensive.

My architect advised me that the Pella windows we are
considering, ~7ft tall by 2ft wide, double-pane air-filled,
would be about $800. I don't remember whether this includes
the 18in high awning window I wanted underneath. So...four in
a row would be over $3K. I envision keeping the awning windows,
but substituting a single window for the four big ones.
As for window "treatments" -- none! We'll be deep in the woods.
No voyeurs, other than deer, little sun in the (Maryland) summer.

While you're considering windows, think air flow too. Think heat buildup. Think rain. (Think overhangs!)

What exactly are you considering you ask in the first post about a custom window-wall that runs the entire length of the house on the overall house elevations that is probably worth $150,000 then come back asking about 2' x 7' casements by Pella no less? What you are asking about in the Pella question are basically standard odd the shelf windows.

A wall of glass like that and the associated complex framing is no where near the same ball park as relatively cheap off the shelf windows.

I'm looking for any kind of specific, quantitative anchor points. Is 8ft x 7ft off-the-shelf? Who woulda thunk it.

Look at the size of "standard" and available sliding glass doors. Thereafter, match the size with fixed glazing, for the additional bays to be glazed, as allowed and required by local codes and you will have a window wall which matches the photo.

In what world does 4 2x7 windows equal an 8x7 window? Not in any design or engineering world they sure don't.

Ah, that's exactly the kind of information I was looking for.
Your windows work out to about $120/sqft. The four off-the-shelf
windows I mentioned come to about $60/sqft. So, for a given window
area, it costs about 2X to go large, for the glass alone.
The end wall of my great room will be about 20' long by 15' high.
So...for a $400K house (well, I hope that's all it will be),
the lower limit of the cost for making that a wall of glass will
come to about 10% of the total cost of the house. The upper limit
will depend on the structural costs for that wall.

No way, a20' x 15' glass wall will be a hell of a lot more than $120 a sq ft. You won't fid cheap that low. Double it as thay may be the dealers cost at $140-180 depending on the mfr.

You don't get to scale up dollar estimates from a standard window to ginormous custom window size. It doesn't work that way. At all. You're gonna die from sticker shock if you base any figures on ''per square foot size''. That won't take into account the steel framing, specialty labor for that framing, or the custom window and custom glass upcharge, nor the custom labor upcharge associated with your inspiration picture. A White Castle is a ''hamburger'', but it ain't no where near a Kobe beef burger served at Old Homestead in NYC. With that inspiration pic as your guide, you better have a major bank account to match. Or pick a different inspiration.

Ughhh .... Sometimes posters on these forums can be so awesome and sometimes... Just plain awful. If you are serious about finding pricing, just send your pictures and your plans if you have them to a company that makes steel Windows and get a quote

If sliders are acceptable, you could do some large Western Sliders that would open in the middle. 20 feet wide (that would be only 4 five foot panels and the frame is pretty thin) is no problem, but I think they are limited to 12 feet high. If you could make that work some how, they would be in the neighborhood of $16,000 for the sliders. They could maybe do some matching abutting fixed Western Slider windows covering the 3-4 feet above for another $5-6000.

Go get a real quote. Sophie is right about the impossibility of extrapolating data from standard to custom. Depending on your locale's energy and impact resistance requirements, the costs could be 4x-10x the cost of standard. They will all have to 100% be safety glass is the only given here. All other code requirements for glazn will be localized.

There is a giant structural difference between a window in a wall, a window wall. Especially a window wall as pictured with 90° corners that must have cantilevered steel supports engineered. That requires a good deal of uncommon to residential construction site skilled labor. That's pulling from commercial construction, with the associated rise in labor costs.

I didn't mean I was thinking of spanning 20'x15' with one
piece of glass. If I divide it into panels of the size similar to
what eb_giac is using in his project, say, then the $120/sqft
I got by dividing $30K by his 252 total sq ft should apply to
my project. Assuming that the $30K he cited is for the cost of the
windows alone, then I can move on to step two, which is
determining the cost of the structural accommodations necessary,
and indeed whether the local building regulations even allow it.
I already know that the windows will have to go now lower than
18 inches above the floor, to avoid having to use tempered glass.

Except for next to a door or misinterpreted as a door. All of which also would need to be tempered. Attempting to square foot residential window pricing is like peeing into the wind in my opinion (even as a basic guideline).

cpacker, I think you might get more input applicable to your situation if you post your proposed plan showing the window opening in question. The more information you give the pros, the more they can help you. Otherwise they can only provide general advice, such as "window walls might require more structural support which would require additional engineering and framing expense." You'd have to give the info to someone to get quotes anyway, so why not here?

Good point basically were all throwing darts, might as well get a target if we can, lol.

Okay...but let me take the original plans to the local
Pella store first. I'll offer the results for comment
in a new thread later.

Pella really?

Just update this thread. And go to a real millwork dealer who offers multiple brands.