Film for the glass and get some large trees growing.

A home with the back facing west will always get the most intense sun in the late afternoon and evening no matter what time of year it is. That's why lots with the backs that face south are always a premium.

Short of wall-mounted patio umbrellas I can't think of anything that will work in that really vast space.

Maybe there is a way to configure a custom sun shade or a custom retractable awning mounted on your beams that could help provide some shade.

Wait till you move in and live with a full season of changes first before doing anything. For instance the rooms inside those windows if a living room will not affect anyone since at that time of day you are eating in the kitchen or dining room and you are not even in the area when you get that setting sun coming in that may last at the most an hour. You maybe jumping the gun on a non existent problem. Inside draperies will help as well as maybe an awning on the outside-motorized IF need be.

Trees are nice :) I have a west face for my front, and the previous folks planned for it with trees.

If you have only been there once and it happened to be 6... maybe try to spend a day there or a couple afternoon into evenings there before making any big decisions. Find out what is really going on with your light play first. If possible, live there for a year before you decide- you might find out that awful 6 PM moment only lasts for a little while before the sun angle isn't bad anymore.

Could it be converted to a screened porch? The screening should cut down on some of the glare in the late afternoon.

Thanks everyone.  I should have been more specific.  Inside the house is fine.  We are trying to figure out how to shade the deck in order to be able to entertain outside there.

Look into a sun screen, appropriately sized for your deck. This one is actually an outdoor shade we use to cover shelves - it’s 10 feet wide and rolls up using a crank Available in various widths, lengths and powered too

Simple math. As the sun heads towards the horizon, and descends past the 45 degree mark, you will need a vertical shade structure to compensate for the low position of the sun as it heads towards the horizon. You know how your house blocks the morning sun?

I would screen in the deck and have a large ceiling fan. On the west side I would add tinted windowns and blinds.

Michelle DeFriez... We have a portion of our deck screened in.  This is a section we wanted open, but need a way to shade if necessary.

ShadyWillowFarm... Yep, exactly why I was asking for suggestions.

fnmroberts... This looks like what we need.  It looks like yours has no side tracks (which were a problem with our stone columns.)  Is it weighted on the bottom or can it be anchored somehow? Wondering for windy days.  

Can you recommend a brand or source?