Our thanks goes to staff member Ricci and her husband Sam for their work.
Purchase 4' X 8' sheets of aluminum backed 1" Styrofoam insulation board. These can be found at most home improvement type stores.
The light weight boards can be easily cut into the size needed with a utility knife.
Cover with batting of your choice.
Wrap the batting to the back of the insulation board and staple into place.
Because the boards are lightweight, they may be easily moved from place to place.
Next, attach sections of extra-wide industrial strength Velcro around the outsides of the board.
Be careful, because this product is very sticky.
Lift the boards up to the wall. Notice Sam used a wood level at the bottom to lay the board on, and then checked to make sure the sides were also level.
If you have a wall that has been highly texturized, you may need to use a liquid glue on the Velcro to adhere the pieces in place.