Danny that is good advice, but as 35 year professional insulation contractor i would disagree with one small point. Radiant barrier is reflective, not conductive. That is the point of the term radiant BARRIER. a good radiant barrier can reflect up to 97% of radiant heat.

The reason i mentioned having air space is that if the product is in contact with a solid surface it becomes conductive, but allow it to stand apart and it does it's job.

While that is true, solar screens are certainly a good option.

The foil/foam/foil products can work as insulations as well as radiant barriers.

The science of radiant barrier only requires that one side be expose to the air, hence the plywood coated radiant barrier products. These only have to have air space on the bottom side to work.

Eddie wanted to cover the window so the RB suggestion.

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