The attic will hit R80. Brazelton is doing much of the traditional renovation work himself, with the help of his father and a few friends. He sleeps inside the unheated, unfinished house on a cot, sometimes with the family's two dogs for companions. The more complicated work is being handled by a professional builder, Ryan Stegora.
Go with an aluminum patch. Use aluminum rivits or screws. Avoid stainless or other metal screws due to the interaction of different metals. Use a sealant like 3m 5200 or Boatlife. Do not use fiberglass to patch aluminum. It just doesn't hold up well.
How to Cut Fiberglass Grating. Cutting FRP Grating is easy if you do it right. You can use the same saws used for cutting wood, to cut FRP. They key is to use a diamond tip blade. If you try to use a regular blade to cut fiberglass grating, it will dull very quickly. This video shows how to cut FRP Grating safely using a standard skill saw.