New Windows

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Feeling the Heat
Feb 6, 2019
Got new windows throughout the house this year. Previous windows and sliding doors were double pane Anderson windows from the early 70’s. Replaced with Renewal by Anderson.

What difference did you notice in wood consumption before vs after new windows?
I have data from 4 previous winters, so I’ll compare as the winter continues
I’d wager you’ll probably notice more of a difference in comfort than in observable savings if the frames and fit were good on the old windows. You probably went from R-2 to maybe R-3 with the new windows.
It's rare that there is economic payback on new windows from an energy savings point of view unless they were the old sash weight style, single pane or in need of sealing. If the old Anderson's were double pane its highly unlikely you will see a significant difference.

If they look okay the better option is cellular blinds with side side seals, they are still quite expensive but they can double the R value of a window and really make a big difference in radiant heat transmission to the outdoors. Even a tight modern window will still be cold to sit near due to radiant loss, add cellular blinds and the radiant heat loss is gone.
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Not much. We replaced 14 single pane double hung (they had storm windows) with decent but not high end windows.

The house isn’t as draft but the floors are still just as cold. Bigger difference was made by air sealing just the big gaps. Getting leaky ducts replaced and seasonal variations probably have more impact
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You might notice it is nicer in the house when it is windy. I started out my carpenter business in 1981 putting in and fixing old windows. My first ones were fixing windows that would rattle and would re putty them. Then we would just caulk them . If the single pane glass rattles , they glass is loose. Just a thin bead of caulk does wonders. A storm also helps a lot. There is not much difference between a single pane with storms and a double pane without storm windows. I put in Anderson 400's and they are fine. However, I put on a few aftermarket storms to see if there is a difference. I have some double hungs that are side by side and two windows in one. I installed a storm on one side and not the other. By morning I noticed a lot less water on the window with the storm on.. Must save something cause the glass has to be warmer .
In my 1926 house renovation, I kept as many of the old wooden double-hung windows as I could. They were in beautiful shape and (mostly) just needed stripping and painting. I did three things to them - 1) I insulated the window pockets by removing the top sash lead weights and making them single-hung windows. Foam went into half of the pockets for an ~R-10 insulation value, 2) I installed bronze weatherstripping in the top and bottom sashes, and 3) I installed an silicon gasket in groove in the bottom of the bottom sash. I didn't need to worry about the meeting rail as they were already pretty tight. I also reburbished and/or had new wooden storm windows built. House is tight (1.0 ACH50) and has low heat loss despite a huge amount of large old wooden windows (1750 square foot house has 18k BTU/hour heat loss at 0 degrees F).
Well, so far this year has been unusually warm, so it’s hard to get an accurate comparison as far as good consumption for this season.

I do notice I am not dropping temps in the house nearly as fast, and it’s more even in the house. Normally if it’s 34ish i need to have a fire in the house on low all day to keep it comfortable. Now I’m only doing 2 loads vs 3.

Supposed to be highs in the teens next week, see how we are doing