We live at about 9,000 ft. above sea level and are about to purchase replacement windows for our home, which still has its original 1978 windows.

The nine vinyl replacements will also be sliders, with the exception of one, which will be an awning type, over the kitchen sink.

The bids we've gotten haven't offered any surprises, really, and we're down to deciding on which contractor and windows to use. Most of the contractors, by the way, will give us bids on just about any manufacturers' windows.

We've gotten bids on:

Alside Sheffield

Milgard Tuscany (triple pane)

Simonton Profinish

Great Lakes

Sunrise Essentials

Accent Windows (a local company)

Simonton 9800

We've pretty much eliminated Great Lakes and Accent because they're probably too high-end for the house. Why put Cadillac windows in a Ford?

I know virtually nothing about the Sunrise Essentials and can't find any mention of "Essentials" as a line on the company Web site (sunrisewindows.com).

Milgard has a "lifetime warranty" but it's pretty vague. Most companies spell out each item, glass package, hardware, etc. They don't mention the glass at all.

That's the most problematic part of choosing a company. At 9,000 ft., we can't have argon or any other gas between panes due to the lack of pressure, which causes the gases to expand. We've gotten any number of answers from the contractors about how they deal with that. One guy said they pinch off the cap tube on installation. One said it will rust shut (it's aluminum!). We've been told we shouldn't buy ANY window manufactured at sea level because they'll bow out and eventually break. The Denver manufacturer assured us that we CAN have argon because the windows are made in Colorado ... but Denver's STILL 4,000 ft. below us, so I can't see the difference.

Aside from the possibility of breaking windows, a big concern is the warranty. Alside specifically spells out that: "The hermetically sealed insulated glass unit of the Alside Vinyl Window/Patio Door System is warranted for as long as the Original Property Owner shall own and live in the property from date of window installation against development of material obstruction of vision occurring from manufacturing defects, resulting from film formation or dust collection between the interior glass surfaces,

caused by failure of the hermetic seal, under conditions of normal use and service."

That's great and all, but since there's a cap tube, wouldn't that make the glass less than "hermetically sealed" and void the warranty? I can't get a good answer on that.

The only company we had briefly looked into, Simonton, actually states that: "Insulating glass units containing capillary tubes (recommended for use in insulating glass units traveling through or being installed in areas with elevations 7,000 feet or more above sea level) are warranted against defects resulting in material obstruction of vision from film formation caused by dust or moisture in the air space for the life of the unit. If such defects occur, Simonton will provide a replacement insulating glass unit at no charge for the life of the unit."

The fact that a company would actually spell that out, makes me think that should the glass become occluded over time on any of the other windows, they simply won't do a thing about it. That part alone makes me think that Simonton is the way to go, but I've not heard anything good about them yet.

Does anyone out there actually have a clue about altitude as it pertains to warrantys? Anyone from Colorado have windows installed and have a problem with the seal after a few years? Anyone with REAL WORLD experience with any of the companies named?

Anyone actually get through this entire letter? :-)