Retractable insulation ideas.

In the process of finishing a walapini. I want to put a sliding layer of either poly or bubble wrap at around 6 feet like flat ceiling to cut down the about of air that needs to be heated at night. Not have any luck with any plans online.

My only thought, and this may be a dumb one, is to secure ropes horizontally every 4 feet or so, threading the ropes through grommets in the bubble wrap or poly, and then pulling them with a rope tied to the center of each width of poly or bubble wrap to spread it along the "ceiling" at night, then open them during the day. I am well aware that there may not be a grommet in your bubble wrap or poly, but I am sure you could find ideas on how to do that online.

The price would be cheap if you used clothes line rope, and they make cheap tensioners so you get get the horizontal ropes taunt.

That is my only thoughts, but it is free and you get what you pay for right? Best wishes on finding a solution to your problem.

I have given this a lot of thought and think that modeling after a garage door or roll up door is the easiest most reliable idea.  Gets harder the bigger the area is though.  Small ones pretty simple to put up two rails and a roll of plastic.  Could be regular poly or something type of aluminized poly like mylar to reflect heat back.

Other low tech option is just to cover the exterior with an insulating blanket. I think I saw a Chinese version that used straw rolls

Edited: you should probably account for condensation and put it on a slight incline with a reservoir to collect/route the run off

Edited 2:  

http://knowledgepublications.com/heat/movable_insulation_full_desc.htm

Joseph Fields wrote:In the process of finishing a walapini. I want to put a sliding layer of either poly or bubble wrap at around 6 feet like flat ceiling to cut down the about of air that needs to be heated at night. Not have any luck with any plans online.

Rather than reinvent the wheel....

http://www.lowtechmagazine.com/2015/12/reinventing-the-greenhouse.html

Now the focus was on a Chinese design that uses insulation. What was prominent is that most of the designs the insulating layer is outside the building. Presume that makes replacement easier. There are a multitude of reflective fabrics that could replace the straw in the Chinese design.  

also...good paper with some drawings

http://aesop.rutgers.edu/~horteng/ppt/papers/MOVABLECURTAIN.PDF

I have 3 thermostatically controlled fans in the rafters of my 22' green house that turn on any time the temp goes above 62F. This seems to work well for me. It also helps move the hot air out in the summer. If you use gas or wood heat you can run the exhaust lengthwise down the ceiling to extract as much heat as possible before it exits.

We are living in a metal building. Insulating it was a big problem. the best solution we found was. Foil/foam/foil. You can buy a foil/bubble/foil at Lowe's but we were afraid of the bubbles losing integrity over time and went with the foam core. We had some left over so we wrapped a water tank we use for roof catchment. That's been a couple of years ago and I am amazed at how well it has held up. It's right out in the weather and the duct tape we put it on with has weathered off a couple of times but the insulation itself is holding up very well. (done right you glue it on with a tube glue) You can buy it in rolls, the stuff at Lowe's comes in folded panels and is a lot more expensive. It's kind of the old joke. . . if I had known it was going to hold up so well I would have protected it better. For a protective coating on things like that I like spray on rubberized automotive under-body. You can get it at Walmart. Check the paint Dept. as well as automotive, they carry a couple of kinds and one is about half the price of the other. The cheap stuff works fine.

Tom Strode wrote:We are living in a metal building. Insulating it was a big problem. the best solution we found was. Foil/foam/foil. You can buy a foil/bubble/foil at Lowe's but we were afraid of the bubbles losing integrity over time and went with the foam core. We had some left over so we wrapped a water tank we use for roof catchment. That's been a couple of years ago and I am amazed at how well it has held up. It's right out in the weather and the duct tape we put it on with has weathered off a couple of times but the insulation itself is holding up very well. (done right you glue it on with a tube glue) You can buy it in rolls, the stuff at Lowe's comes in folded panels and is a lot more expensive. It's kind of the old joke. . . if I had known it was going to hold up so well I would have protected it better. For a protective coating on things like that I like spray on rubberized automotive under-body. You can get it at Walmart. Check the paint Dept. as well as automotive, they carry a couple of kinds and one is about half the price of the other. The cheap stuff works fine.

Tom,

Where did you get your rolled insulation from? If it is pliable it sounds like something that would work well for covering windows etc.

http://www.insulation4less.com/default.aspx  

It is flexible but it's reflective not see through. I use bubble wrap over windows to let the light in. I went out and looked at the tank and it is showing deterioration on top but on the sides where it's vertical it looks good as new except for some obvious impact damage, and it's been up for at least two years.

Thank you very much,

I am looking for insulation that I can move in front of my windows/roof of a "green house" room in a barn, so similar situation as the OP has. As such I would be covering things in the evening and opening them again in the morning. More as a way to maintain the heat then to leave it in place all day long.

Barring exterior insulation, I'd build joists over the walls but under the roof, and put your preferred sheet film over them which you would roll/unroll into place with a greenhouse-style sidewall ventilating rod & handle combo. The end walls under the rod handles would be tricky to air proof, but you could hang vertical film walls INSIDE the ends of the overhead roll to take care of that if you wanted.