Window plugs

[Frank Lee]

A long time ago, on a forum far, far away....

someone suggested plugging windows in the house with sheet foam. I kinda poo-poo'd it, saying it would turn the rooms into black holes.

Well I need to partially apologize to whoever that was.

I've made a bunch of plugs from cast-off white styrofoam sheet and yes, the rooms get pretty dark. BUT...

I've made about half of the plugs easily removeable and I take them out whenever it's light out, and put them in whenever I'd turn the light on in the room anyway... basically overnight. The removeable ones have been "bordered" with 2" clear tape so that millions of little balls don't slough off every time they're handled.

I haven't quantified how much good they do, but I'd sure think they help, and I think they would be better than the interior clear shrink plastic I'd used in the past. I suppose a guy could go online and find insulative values for crappy old windows, and values for various thicknesses of styrofoam sheet and come up with some sort of estimate.

It won't really show up in the utility bills unless I also have information on degree-days for those periods.

Anyway, they aren't much trouble aside from the huge mess I made cutting them with a knife. Oh, to have a hot wire foam cutter.

[Duffman]

Frank,

Great post, i'll add, the black holes may lower your cooling bill in the summer. Keep the foam white or maybe put aluminum foil on one side to reflect light out in the summer.

[Bicycle Bob]

I had some scrap aluminum-faced foam available last year, so I made some of those, too. Some days, when the sun is on the snow on the north side of the house, the panels actually warm up facing triple glazing. However, the rest of the time, they sure keep heat in. On a cold day, I can feel a cold breeze shooting out of the small crack I left at the bottom, so I'm planning to edge my panels in soft foam and fabric to make them a press fit.

[Frank Lee]

I have one piece of foil faced foam in one window; I was originally going to put it underhood but my car doesn't have the room.

I was considering putting a light coat of flat black spray paint on the outer surfaces of the plugs in the southern windows, justa make sure the whiteness of em wasn't cutting my solar gain back too much on the ones I don't take out and/or when I don't take them out early enough.

[The Atomic Ass]

Originally Posted by Frank Lee

It won't really show up in the utility bills unless I also have information on degree-days for those periods.

Anyway, they aren't much trouble aside from the huge mess I made cutting them with a knife. Oh, to have a hot wire foam cutter.

I didn't use foam, I just hung a comforter in my patio door opening. Doesn't fully cover the thing, so some light and cold still leaks through, but not enough of either to bother with. Despite it being progressively colder, my power bill (all electric heat), has gone down month after month from November. January's the lowest yet, and I use the hell out of my lights anyway, as I'm a creature of the night.

I actually find at my present level, I can shut off all my heat at ~45F outside and I stay above 60F, due to convection from the apartment below me.