I know there are a million different variables, but on average, how much of your total budget should you spend on windows? I've always heard things like "kitchen is 20% of your total budget", etc. I'm trying to figure out how much more it might cost to upgrade to more efficient windows. If in a "normal" build I could expect to spend 5% of my budget on windows, & to upgrade it would be 7% (completely making up these numbers, btw) it would help me to get some ideas. I've learned a lot about green/energy efficient building, but windows is one area where I still feel pretty clueless.

I can tell you from a new home build experience what I figured out. I went with triple pane, low e squared argon r8.3 (advertised) windows and ended up in vinyl. I have 5 doors (two big,one french, and two regular), and 31 windows all quite large (6'x2' average). I ended up paying $31 000 for all this and it was quite close between three major manufacturers and does not include installation. I had a quote for wood and it was closer to $45 000. My budget for this house build is around $350-400 000 doing almost all the work myself, the banks budget for me was $900 000 so I don't know what percentage you want to base that on. The windows and materials to install basically cost about the same as all my SIP panels and floor joists for a 2600 sq foot two storey house. I actually have some specific prices if you know sizes of windows. Sean

I guess one more thing, dual to triple cost me $5000 more, extra glazing was $1800, and the extra 1/2" jam (7") for the SIPS was $2000. That gives you more of an upgrade idea I guess. Sean

accurate estimates are based on actual prices not on %, a  $ 300,000 home might have $5 to 15k in windows depending on the design , to merely throw a percentage number at it is a recipe for disaster and the reason I loathe sq. ft. and ballpark prices

While I can understand what you're saying, I think it serves a purpose - to get a starting point, if nothing else.  Using your example, $5k-$15k would be roughly 2-5% of the total.  Here's how it would help me--

Let's say my budget is $300,000 & I know that windows are typically 2-5% of the total.  If upgraded windows cost 30% more, 50% more, etc., it at least gives me an idea of the hard dollars that I'm spending.  Now if I know that I need to spend an extra $7000 on windows, I need to think about other aspects, can I justify it, etc.   Keep in mind, I said that I really have NO idea what to expect for windows.  I would never take a "x% of total" as a bid or anything, but we're still in the early stages & trying to figure out what's feasible & what's not..

thanks for your feedback!

jerkylips
Take the time to run a computer simulation of the construction using one of the simple programs mentioned in these forums. You can plug various insulations, window values etc into it & see the variations in the results. You may find that it will be more beneficial to add foundation insulation or increase your wall values than to change the windows - or vice versa. It will be time well spent.
Bob Irving