Insulating a hole in the wall
 

I have an approximately 7' wide, 7' tall hole in the wall of my apartment, affectionately called a patio door. :D

It just so happens to have an R-value of near 0. The building is slightly crooked, and the upper portion of the door does not close in the track, rather I have about 1/8" of visibility to the outside where there should be none. :eek:

And obviously I've tried sealing this, but I don't know how much good it's doing. I've used the tape-up plastic, but it still seems to want to stay below 50F on that side of the room, and I'm using an insane amount of power trying to keep just this room warm.

Which got me to thinking. I can take as much scrap cardboard from work as I want. Am I thinking correctly, that a few layers, perhaps 4-5 of double-wall cardboard might provide some decent insulation? Is the R-value of cardboard significant enough for this?

Hello,

Trapped air is how you gain R-value. I would try 2 layers of 6 mil plastic, each taped tightly to all surfaces, and if possible, with a 1/2-3/4" of space between them. Calulk the gaps around the frame first.

If you can get to the outside of the door then get some of the outdoor window plastic to seal it, then make a foam plug that fits the opening, or like you said a cardboard plug, taping all the seams and edges and if you did another sheet of plastic on the inside you would keep moister from freezing in there, then hang a curtin of choice over it.

Bubble wrap = the bomb.
It isn't for sealing gaps so much; but you can spray the glass with water and stick the smooth side right on the glass.

Obviously not for every application though . . .. .

Do you use the door at all? If not, multiple layers of cardboard, or bubble wrap if you want some light, should give you an R-value not too much less than standard insulation of the same thickness. As was mentioned above, it's the trapped air that does most of the insulating, and corrugated cardboard should do that pretty well.

I'd try to run the corrugations horizontally, rather than vertically, to minimize any convection.

It's a second-story deck with a 3' railing, so while I could technically get to it, it wouldn't be very easy.

Also, my attempt at hanging plastic indoors was mostly unfruitful... The plastic simply will not stick to anything on the lower portion, forcing me to hold it down with a wool blanket. The upper portions also pull off a little bit at a time, requiring me to go around tacking on more tape. I don't think either the tape is very good, or the frame is very stick-worthy. I did clean it as thoroughly as I could before applying the tape.

I would have hoped my plans would have left little doubt in that department. :D

Now I'm starting to wish I hadn't loaned out my giant roll of bubble wrap. :(

And a modified plan: I have a rather large sheet of MDF hanging around in my parents garage, that I no longer intend to use for it's original purpose, so how about the MDF sheet, with a layer of cardboard on each side, jammed tightly into the wall around the door, (the door is recessed about 3"), with cardboard shims to hold it in place around the edges. That may give this project the structural rigidity that I was looking for.

first thing you want to do is seal it from drafts, that is why I suggested plastic on the outside, but even duct tape over the crack would work, then you want to make as many tiny air pockets as you can, foam does this in a ridged sheet that you can cut to fit cardboard does this in thiner sheets that can be stacked together, bubble wrap, or reflectix has larger bubbles but works, fiber glass bats or blankets work as long as their isn't a draft.
if you plan to stay there next winter as well then you might invest $20 in foam and some nice looking fabric to make a custom size plug that you press in to place.

Sounds like you are in an apartment? If so, see if you can have the building supervisor or owner do something to improve the door, as it IS their responsibility.

Otherwise, it sounds like your main issues are drafts, light, and insulation value of the glass itself.

Bubble wrap does do a good job of increasing the R-value of glass, while still allowing light to come through. I am not sure of the lighting of your place, but my old apartment was very dark, and I wouldn't have covered a single window there, just to make sure I got some daylight!

The big thing is just to seal up cracks any way you can! Foam, caulk, fiberglass,old socks. Just make sure it's something that will keep out moisture too, so maybe not the socks...

A 2" thick sheet of extruded polystyrene foam costs around $20. It would be around R-10, is easily shaped, and easy to decorate. You can pin cloth right to it to make it look nice. I wouldn't be a bad idea to cover the exterior side of it either, so your neighbors don't have to take a look at that big pink sheet of foam all the time.

Another good insulator, foam packing peanuts. We used those to insulate a non used door once, with plastic on the inside to hold the peanuts in place. It was free, we found the peanuts on the university next to the dumpster. It took both 55 gallon bags to insulate the door, but it worked well (it was a mess to clean up, when we left, but great for both summer and winter).

I would like to have them do something about it, but probably not this time of year, and I can tell from looking at, it's going to be a MAJOR, (read, whole new door assembly), project. I'll probably talk to them in the spring about it.

Light isn't really an issue. I have an open dining room, with a chandelier, with 5 100we CFL's, and 4 lamps around the living room, also with 100we CFL's. I can get it brighter in here than the sun can. :D

About how big do those sheets of foam come? I measured, and my opening is 80"H x 70-9/16"W. I'm actually trying to do this on a budget, as my recent power bill has wiped out most of my spending cash this month. :(