Thermal Insulated Curtains
1869farmhouse
| Posted in General Questions on
I’ve been meaning to buy some curtains for a bit, but we have -7 F temps in the forecast for next week, so my heat pump is going to need all the help it can get.
Does anyone have experience with a decent heavy/thermal curtain?
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One consideration is that the benefits are limited unless it's at least somewhat sealed all the way around.
One good option is discussed here: https://www.greenbuildingadvisor.com/article/insulating-window-shades
Make sense. I need curtains anyway, and prefer to have a blackout with something sheer underneath. My last house had these HEAVY blackout curtains that I hung tight against the wall that hung down to the floor. They sure seemed to help on the freezing cold days, but maybe it was in my head.
Just as a bump, I’m curious about the lack of info on this topic. Is the idea that the heat loss of the room is not affected much by heavy curtains? While that might be the case, anyone that’s walked past a single pane window when it’s 10 degrees has felt the “cold” radiating from the window. This goes away with a heavy curtain. Is it just “feel” and not measurable?
There is a real difference in the effect on feel, depending on the heat loss mechanism: heat lost through convection behind the curtain won't be felt as much as heat loss by radiation to the surface of the window, which is blocked by the curtain. And a curtain that goes all the way to the floor will impede convection more than one that hangs with the bottom open to air flow just below the window.
So you can improve comfort a lot with any heavy curtain, but you'll reduce energy costs for heating more if you seal the edges.
Cold weather can definitely make you want to keep the heat in.
Many years ago I installed honeycomb insulated shades with side tracks. I never measured the savings in heat as I mostly use wood, but they make a huge difference in comfort. Before I felt cold when I sat near a big window. As soon as I lower the shade I feel more comfortable. Brand names come and go, but search for honeycomb shades with side tracks. The side tracks prevent air from circulating around the window and limit condensation on the windows.