When it comes to estimating the weight of an existing roof field verification of the in place construction is necessary.
Roof insulation weight psf.
Thickness 12 0 gypsum fill per 1 in.
A built up roof for example will typically include the built up membrane itself with or without gravel as well as some kind of insulation and cover board which will vary in thickness from roof to roof.
9 aug 17 15 48.
Thickness 12 0 ceramic or quarry tile in.
Thickness 2 5 floors and floor finishes asphalt mastic per 1 in.
Asce states that rigid roof insulation weighs 1 5 psf per inch of thickness whereas polyiso insulation like thermax is 0 25psf per inch.
Thickness 3 4 10 0 concrete fill per 1 in.
Thickness 5 0 lumber sheathing per 1 in.