R-8.6 windows

[EatenByLimestone]

I like the way they open.

 

[Wildo]

Those are nice.

 

[Grisu]

Tilt and turn is totally standard in Europe. My parents put windows of that type in their new home in '79. I have never quite understood the complicated opening mechanisms here. Double-hung just don't seal that well and casements need all that cranking. Consider also how easy it is to clean a t&t window.

Now, my parents' windows never had such an impressive r-value.

 

[jebatty]

The tilt part of this window I get, but do you really have to swing the window into the room to open it? No furniture above the bottom of these windows, and my desk as I type this would be a no-no if I want to open the window. And then in buggy/mosquito country like where I live, where does the window screen go ... on the outside? Our house would be a zoological haven without window screens.

The R-8.4 is a vast improvement over the R-3 typical window of today's energy efficient house, but it is not new, uncommon yes, likely because of cost of the glass and substantial framing for tight seal. It was 1992 that we bought our first replacement windows, the Insol8 made by Hurd. This was and is a R-8 center of glass window -- two glass panes with two "panes" of plastic film between the inner and outer glass panes. I don't know the overall R or U rating of the window, but it is very good compared to all other windows I have seen since. Our windows never fog from humidity or have dripping condensation on the window sills in the winter, even the window above the kitchen sink; the glass on the inside is warm to the touch, even with -35F outside temps; and there is no cold air wash or draft around the windows -- let the winter winds howl. On the coldest and windiest, worst winter days my wife can sit in her easy chair reading a book right next to the 25' of 5' high glass on the SW wall of our house, the same wall that catches both the NW winds of very cold MN winter and the passive solar from the low winter sun.

Windows up to R-11 also are available. WOW And I recall some years ago what I think was the Aspen Window, an R-12 window.

With these new window, window energy efficiency is near or better than standard wall construction, and these windows can have a net energy gain rather than loss with proper passive solar location.

For us the very high price of extreme energy efficient windows made our house with lots of glass a cozy and comfortable place to be in the extremes of MN winter.

 

[dznam]

We installed those same windows (Intus) in a timberframe/sip panel house we built last year. The u value is "whole window", not just the glass or center of glass. Frames are generally the weak link in the thermal value of a window and US manufacturers (especially) like to mislead consumers by giving glass u values (or even worse, center of glass) when whole window u values are usually much weaker. Intus also customized (no additional cost) the SHGC of each window in our house, depending on it's directional orientation.

We're ecstatic about the widow's thermal performance, operation, flexibility (tilt and turn) and ease of cleaning. They are built like Fort Knox and require an extra set of hands or two to set them in place when install in ROs because of their weight. Only downside for us was window shades - tilt/turn means there are no workable and easily available alternatives. They had to be sourced from Europe and were about 2x the cost of a nice set of Hunter-Douglas shades.

Screens install within the widow frame and outside the glass and are completely effective in keeping the bugs out - no different from the widows most are familiar with.

 

[Grisu]

Frames are generally the weak link in the thermal value of a window and US manufacturers (especially) like to mislead consumers by giving glass u values (or even worse, center of glass) when whole window u values are usually much weaker.

We got some Marvin casements installed a few years ago and I can readily see what you mean. There are places in the frame I can look right at the outer layer. They are better than the ones we had before but I am really wondering whether they get their advertised r-value.

We're ecstatic about the widow's thermal performance, operation, flexibility (tilt and turn) and ease of cleaning. They are built like Fort Knox and require an extra set of hands or two to set them in place when install in ROs because of their weight. Only downside for us was window shades - tilt/turn means there are no workable and easily available alternatives. They had to be sourced from Europe and were about 2x the cost of a nice set of Hunter-Douglas shades.

It is true that shutters usually run on the outside but blinds are not that uncommon and I have not noticed any real difference to the ones sold here. What exactly was the problem you encountered when installing shades with your windows?

 

[dznam]

It is true that shutters usually run on the outside but blinds are not that uncommon and I have not noticed any real difference to the ones sold here. What exactly was the problem you encountered when installing shades with your windows?

Picture a window that tilts in 6" at the top and also swings in at least 90 degrees. If you attach the shade to the upper window jamb (or even the jamb extension), you cannot open the window in either inswing or tilt mode - the widow's upper sash will hit the shade even if it (the shade) is in the "up" position.

The solution is to attach the window shade directly to the upper sash or to the glass itself so that the shade "travels" with the window as it opens in either direction. You also don't want the shade to fall away from the window when it's drawn and operated in the tilt mode, so it needs to be fastened somehow to the lower sash or glass just above the lower sash. Additionally, because there is limited clearance between the glass and the handle which operates the tilt and turn (the operation of the handle requires its movement from parallel to the side sash to perpendicular to that sash, which places it about 4" into the glass), the shade and its mounting hardware must be sufficiently low profile to fit between the handle and the glass.

I hope that made some sense. If not, let me know and I'll give another try at explaining. I looked everywhere for a U.S. solution because my build budget was groaning loudly at that point and because I try my best to be frugal.

Frames are critical - the key is to getting an effective thermal break and the Europeans have this down to a science. On a typical U.S. window, the R value of the frames is right around 1 (wood) and typically less for vinyl and aluminum. I am told that the impact of this on "whole window" performance is in much greater proportion to their overall contribution to the exposed surface area of the whole window because of the "chimney effect" of heat flow (the science is beyond me). Additionally, the air sealing of double-hungs is problematic and this is not accounted for when U or R values are reported. These Euro windows also have non-conductive edge spacers, much wider spacing between the glass panes and multiple dogs which effectively air-seal the window when in the closed position.

When we did our research we found that there were a few Canadian manufacturers making quite efficient windows as well as a few boutique U.S. manufacturers and the U.S. "majors" were only slowly coming around.

 

[jebatty]

Based on the explanation of these Euro windows, and I have seen other Euro windows of similar construction while in Europe (of all places!), a person has to agree that they are superior in many if not all respects.

I detailed above our experience with our Insol8 windows, and I have no disappointment at all with the performance of our windows in the extreme MN climate, save one: the tubular weather stripping on the sash is becoming brittle on some of the first windows we installed (now 23 years old) and needs to be replaced. I called the company last fall and replacement weather stripping remains available. It will be easy to install. We have 23 of the Insol8 windows installed, most being 2' x 5' casement, next awning style, and then 3 picture windows, the largest being a double at 8' x 5'.

As is usually true with quality products, you get what you pay for. High quality windows make a lot of sense to keep a house cool in the summer and warm in the winter. For a 1956 house, with windows and lots of them on all four sides totaling about 45' in window glass width, 1500 sq ft + full walkout basement, and being able to heat the house with 4 cords of aspen stove wood + electric supplement in the basement (1 aspen cord equivalent in heat value), I am sure that the windows have a lot to do with very substantial energy savings we experience. And the comfort and enjoyment of being able to sit by any window, especially the 8' picture window, and look at glistening snow crystals on a -35F day feeling warm glass and no draft is priceless.

 

[dznam]

As is usually true with quality products, you get what you pay for. High quality windows make a lot of sense to keep a house cool in the summer and warm in the winter. For a 1956 house, with windows and lots of them on all four sides totaling about 45' in window glass width, 1500 sq ft + full walkout basement, and being able to heat the house with 4 cords of aspen stove wood + electric supplement in the basement (1 aspen cord equivalent in heat value), I am sure that the windows have a lot to do with very substantial energy savings we experience. And the comfort and enjoyment of being able to sit by any window, especially the 8' picture window, and look at glistening snow crystals on a -35F day feeling warm glass and no draft is priceless.

That's an excellent point you bring up. The comfort that comes with efficient windows, no matter their origin, is really noticeable and never fails to bring a smile to my mug on those cold and windy winter days though we don't get too many of those at -35F here on the coast!

 

[Grisu]

Picture a window that tilts in 6" at the top and also swings in at least 90 degrees.

That's easy; I lived with those windows for 25 years.

If you attach the shade to the upper window jamb (or even the jamb extension), you cannot open the window in either inswing or tilt mode - the widow's upper sash will hit the shade even if it (the shade) is in the "up" position.
The solution is to attach the window shade directly to the upper sash or to the glass itself so that the shade "travels" with the window as it opens in either direction. You also don't want the shade to fall away from the window when it's drawn and operated in the tilt mode, so it needs to be fastened somehow to the lower sash or glass just above the lower sash. Additionally, because there is limited clearance between the glass and the handle which operates the tilt and turn (the operation of the handle requires its movement from parallel to the side sash to perpendicular to that sash, which places it about 4" into the glass), the shade and its mounting hardware must be sufficiently low profile to fit between the handle and the glass.

It totally makes sense but I am pretty sure I have seen blinds that were not attached to the actual window but above to the "jamb". Maybe next time I am there I will see if I can find one to see how it works - just out of curiosity.