At least for spacecraft a similar product is used. Altough it doesnot consist of bubblewrap and alufoil. The stuff used consists of various layers foil of carbon fibree, glass fibre, zilver, and aluminium alloy. Its higly heat resistant and reflect almost 100% of the heat and radiation protecting the craft.
The products on the market for building insulation does work but not entrely as state. A shed heatsup or cools down through 3 processes; transport through flow (convection), radiation and conductance. Traditional insulation materials only work to reduce the amount of convected heat loos / warm up. This material only reducted loss and warmup by radation.
Surfaces that are in contact of each other have high conductive properties. In a building with doudle walls there is not that many of contact area. Most heat is transferred through air flow and radiation.
The heat conductivness of non moving air is very low. Traditional isolation traps as many air in small pockets. The air ceases to move and no heat is transfereed by convection (transported by air flow)
Heat is only transferred by radiation between to surfaces that have some distance between them and are in line of sight. (heat radiation is infra red light, some things are transparent for infra red light that are not for visible light and vice versa)
For a double wall without insulation in between the sun heats up the outside wall through radiation. The outside wall heats up the inside wall through radiation. Through convection and a little conduction the room heats up. The same stands for the heating in the winter. The warm inside heats up the inside wall which radiates its warmth to the outside wall....
When a double wall is fully stuffed with insulation the entire wall construction is heated up by the sun's radiation. The wall again heats up the room by mostly convection. Because of the insulation material the room heat up is delayed but not prevented. (in the winter again all the same but in reverse). Traditional insulation that has a layer of alu foil does not add much to the insulation it's main purpose is a moister barrier.
When you place a reflector in between the wall and the sun the heat up is stopped. The same when a reflector is placed in the middle of a double wall without insulation. But this radiation is only reflected if there is radiation. There has to be free space between the reflector and the walls. About near to 1" at both sides. For the insulation to work the insulation takes up about 2 1/4 " of room. Traditionsal insulation of the same thickness gives about as much amount of insulation some materials such as polyisocyanurate gives more.
When only using the multifoil there is still alot of heat loow in the winter heat up in the summer. The convection has not been stopped. Heat is still transferred through air flow. When not combining the reflector with traditional insulation you don't have the claimed high insulation.
To have these high insulation figures for both winter and summer you need the inside wall/ceiling, an free space of near 1", the foil, a free space of near 1", about 3" of traditional insulation, a near 1" free space, the foil, a near 1" free space, the outside wall/roof
Hope this helps
