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coolmom42's avatar
coolmom42
Explorer II
Oct 03, 2020

Reflectix on window, long-term?

I want to block the rear window that's over the bed, in the rear corner of my motorhome. Is there any issue with fastening bubble layered Reflectix to the inside, and leaving it there indefinitely?

My main concern is excessive heat buildup between the Reflectix and the window, that could crack the window. The plan is to block up this window, remove the valance and shade, and install a faux headboard across the wall above the bed. I don't want heat buildup between the headboard and window, thus the Reflectix.

I like to sit up in bed to read or work on a laptop, and the window and shade are just a big nuisance. There is another large window on the side, so there will be plenty of light remaining.

If not Reflectix, what else would work that would look decent from the outside, and block incoming heat effectively?

19 Replies

  • I have used it for more than 6 years in the window of the overhead bunk,to keep the heat down and keep from sun bleaching the curtains,it faces east when stored here at home.

    There has not been any downside to this or any problems. I also use it in the rear and side windows while stored here at home and also camping when needed.

    The nice thing I like about it over the solid,which I tried,if you want to see out all you have to do is take it down and roll it up for easy storage. Not so on the solid boards,always a storage problem,I found it was a real pain.
  • If not Reflectix, what else would work that would look decent from the outside, and block incoming heat effectively?


    No worry of heating the glass or condensation on chilly nights.
    I use solid foam insulation, DOW board from H. Depot or Lowes. Yes I know its pink, I had to paint it flat black to blend with my window trim and tint.;) Its inexpensive and easy to trim. Sometimes on some windows I use one sheet other windows I use two to double the thickness. Depends what fits better.
    I think the R value is 5 for the 1" board. But using one thickness works fine. It never transfers the cold or heat. It makes a decent difference.
    If I decide to use the window in its original form then I simply remove the insulating panel and store it under the mattress where it won't get damaged.

    If you decide to do this:
    1. Cut a snug piece to fit within the window frame so its held in place by pressure, tape it place or the shade helps to secure it if its snug enough. I cut it a little large then trim it down to fit snug.
    2. I cut a 10x10 square in the middle so I could see out. I covered the square with Clear Window Insulating (heat shrink) Film. The window kit includes the sticky tape to secure the film to the DOW board.
    3. If you need it to be thicker, then double the board thickness with the square cut-out of it to match the first piece. No need to heat shrink cover the second piece, one layer is enough.
  • wopachop wrote:
    To my understanding the excessive heat is not good for everything that seals the window. I have foam board in my windows. Put the foil to the outside. Posted it here and several old school fellas said to flip it around. Dont put the foil to the outside. I listened to them, but i didnt follow the advice. So maybe i listened to Hendrix, but did i hear him? (white men cant jump joke)


    So has anything terrible happened with the Reflectix on the outside? and how long have you had it on there?

    I'm thinking maybe the foam board would be just as good, without the Reflectix. My goal is to avoid a hot or cold spot behind my fake headboard.
  • Flyfisherman128 wrote:
    Why any builder thinks you need 2 huge windows by a bed


    Its so when your arm hits the blinds in the middle of the night, your wife knows it


    Haha I believe that.
  • To my understanding the excessive heat is not good for everything that seals the window. I have foam board in my windows. Put the foil to the outside. Posted it here and several old school fellas said to flip it around. Dont put the foil to the outside. I listened to them, but i didnt follow the advice. So maybe i listened to Hendrix, but did i hear him? (white men cant jump joke)
  • Why any builder thinks you need 2 huge windows by a bed


    Its so when your arm hits the blinds in the middle of the night, your wife knows it
  • DrewE wrote:
    Heat buildup from the Reflectix won't be any problem at all. Heating glass leads to cracking mainly if it's not even, or if the glass is mounted in such a way that it cannot expand or contract sufficiently to take up the stresses; and in any case, the Reflectix won't cause the glass to be noticeably warmer than if the window were covered with, say, a typical curtain.

    If the window in question is an emergency exit window, you oughtn't block it such that you cannot escape quickly in the event of a fire or similar problem.



    Thanks!

    The exit window is the other one beside the bed.

    Why any builder thinks you need 2 huge windows by a bed, is beyond me.
  • Heat buildup from the Reflectix won't be any problem at all. Heating glass leads to cracking mainly if it's not even, or if the glass is mounted in such a way that it cannot expand or contract sufficiently to take up the stresses; and in any case, the Reflectix won't cause the glass to be noticeably warmer than if the window were covered with, say, a typical curtain.

    If the window in question is an emergency exit window, you oughtn't block it such that you cannot escape quickly in the event of a fire or similar problem.