RetireJapan

Okay, I did this today, so here we go. One shot here is the "before" image, but really, that's also just what it looks like now that it's done--maybe just ever so slightly darker, since the plastic does cut a little light.

The other shot is the first stage of this. I've moved the couch out, and then some chairs over at the windows so that I could take the curtains down. The chairs (and there were a couple more later) allow me to more or less walk back and forth along there, to deal with the tape and plastic up high.

Wall to wall is 5300mm, top to bottom is 1800mm. Big. The windows are already double glazed, one thing we replaced a few years after we moved here. Tho good, as I said elsewhere I've taped the vertical edges outdoors, also use some thin foam weather-stripping to further aid the seal. Last year I didn't put the plastic up, this year energy prices are up, so...

Hard to see here, but you'll see in the following pics that I've added two vertical strips of wood on the left and right walls, which meet up with what I call the 'lips' top and bottom that are already there. These strips are maybe 12mm or so square.

Really recommend the 'inplus' style inner windows for a more permanent solution. We used to do bubble wrap or plastic sheets, but having double glazing inplus inside the original double glazing is wonderful.

Very reasonable if you can fit it yourself, not too bad to get it professionally done. Takes a couple of hours to install the made to measure units

Here are a couple pics of the right side, top and bottom. The top along the ceiling and the two side I use double-sided tape (両面テープ). The backing is white, not yet removed/pulled off. I do the top first, getting the plastic on all along there, and once that's set, pull the white off the sides and try to tension up the plastic on each.

Getting the plastic ready here. Top to bottom is 1.8 meters. Once I got some plastic that was exactly that, and it didn't work!

The plastic on the roll that's there is folded in half, so the true width of it (what will be top to bottom) is double how long that roll is. Also, the roll seems endless, I'm not sure how many more years I'll get out of it.

Since the overall window width is 5.3 meters, take about 7 meters off the roll so there's extra on each end. What happens is the right side, where I start has about 50cm 'extra' to trim away, with lots more extra on the left end.

Before I forget, the plastic is almost certain 1 mil.

Next, I've got it attached along the top, and there's no extra along there--I put the top edge of the plastic right where it's supposed to be.

On the left and right wall, there's the 'extra'. Here's the left side with the extra kind of bunched up, and then the same with the extra trimmed away. I used a cutter/razor knife and just run it down the edge, not too difficult.

Note the overhang along the bottom, that's the next step.

Okay, the bottom. Instead of tape along here, I use some thin strip of wood, I think they're 3mm x 12mm (and 900 or 910mm long).

I pull the plastic a little tight, and put a strip against the bottom, and use a staple gun to tack it in place, maybe three staples per 900mm. It takes three of these strips on each side, one cut a little shorter to fit.

Note the overhang below--there was much, much more, but I've already trimmed it off all across to about that much below the bottom of the window.

The extra there is going to be wrapped/pulled up and taped against itself, kind of a loop around the wood strips.

Like this. I first tack it in place with little bits of tape, then use 50mm cello packing tape to close it up good.

Last pic, the plastic is done. As you can see (can't see?!?) no view now. But winters are dark and gray here, rainy/sleety/snowy and all that. There are other windows to look out at that. Here in the living room, the sheer curtains are always closed anyway.

After this, the work is simply to put the curtains back up, put the chairs away, run the vacuum, and make it look like the "before" picture in the first post up above. With the sheer curtains closed, you don't really even know the plastic is there.

These windows face north. Stand facing the windows and true north is a little to the left, about 10:30 or 11 o'clock. There's about six weeks in June when we do actually get some morning sun coming in these windows.

This was about three hours work. Taking it down is quick--I move the curtains to the middle but don't take them down. I try to salvage the wood strips to reuse, pulling them off carefully, pliers to pull the staples. This time I had it all on hand, not a single thing needed from the home center.

Another way to do this as DIY is with PVC frames sold by a company called Hikari. Some home centers, Cainz Home at least, stock the kits. The link is just one example. The kit does not include glazing, just the runners that fit in the window and the framing to go around the glazing sheet. For Google searches try "DIY 内窓"

https://www.cyber-reps.com/easywindow/Kit1.html

They suggest you do it with rigid polycarbonate, ribbed 4 or 4.5mm sheets with an air gap, that are mostly transparent except for the ribs. However, depending on the size and how much of the 1820 by 910 home center sheet you waste, it may actually be cheaper to get custom made 4mm acrylic sheets that are solid and almost perfectly transparent. This would look much higher quality, almost like professional uchimado by YKK/Tostem. If you remove and store the window part in spring, all you are left with is some plastic channels on your window frames. The kits I've seen come in white, dark brown, and light wood colours. You can also buy the individual parts in the kits, which may be cheaper.

Polycarbonate or acrylic sheets are reusable, can be used to make inner windows that are openable, and much more attractive than soft plastic film. The insulation value will also be higher. The price will be higher, but still way cheaper than professional storm windows/secondary glazing/uchimado. If you do not need a smaller window to open in winter, you could just fit a single polycarbonate sheet into or over the window opening, with or without a frame as you desire.

RetireJapan wrote: ↑Thu Nov 11, 2021 10:45 am Really recommend the 'inplus' style inner windows for a more permanent solution. We used to do bubble wrap or plastic sheets, but having double glazing inplus inside the original double glazing is wonderful.

Very reasonable if you can fit it yourself, not too bad to get it professionally done. Takes a couple of hours to install the made to measure units

Sorry that I missed your post as I was getting all those separate posts done...!

Another set of windows would be good, but each half of that window walk is about 2.6 meters wide (and 1.8 tall). That'd probably be some serious money. One of the four window panels that's there has a leak--some condensation on the inside. It might be better to replace them all with fixed glass, triple glazed--a little more r-value, and no leakage.

And DIY--the windows that are there are too heavy for me to take out/put back in, just move them back and forth to clean the tracks and wash the glass once in a while in place. Even single pane/glazing that was the same size would be hard to handle, and double would be two sheets of glass 1.8 tall and 1.3 meters wide. Very heavy. Even for two people who knew what they were doing.

This time/installation was free. Next year I'll need to buy another roll of tape just in case, as a back up.