How do you calculate the number of packages of bundled shingles required to reroof a residence?

well-known shingles in item development: question kahiemstra : How do you calculate the necessary number of packages grouped shingle reroof a home I know the square footage of the region to be covered with shingles. I am with architectural shingles. I know that the shingles in bundles of 26 or be delivered. Considering that only a portion of the shingle is exposed, I know I will have shingles much more square feet than I did from the roof surface. How do I calculate the very best response :

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