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.
If in doubt, bring in a sample of the broken glass to our shop and we'll advise the proper glass to be used for replacement. Single strength costs around $2.50 per square foot and double-strength is around $3.00 per square foot. Aluminum windows that use the u-shaped vinyl gasket must use the same exact glass thickness.