How much do new windows save on utility cost?

[Laura Williams]

For those of you who have fully replaced old windows & installed new ones in your personal or rental properties I’m curious what percentage it reduced your utility bills.

I have an apartment unit that has 15 large old windows and has been getting high electric bills (electric furnace and no dishwasher or washer/dryer and temp set at 70) and I’m wondering if it’s worthwhile to replace the old windows. Curious the reduction in people’s bills after full window replacement on their older properties.