A subframe configuration for a retrofit roof includes a subframe connected to the upper surface of a rib on an existing roof. The subframe is also connected to the valley/purlin of the existing roof. The connection can be a mechanical interference connection or one that is formed by a mechanical connector. The subframe of the disclosure includes a rib flange that extends from the bottom of the lip. The rib flange is disposed substantially parallel to the base of the subframe. When installed, a connector extends through the rib flange into a rib of the existing roof. Rib flange can be continuous or provided only at each or just some of the ribs.

A retrofit roofing system with a roof furring having a substantially flat top and L-shaped side with openings that correspond to the raised portions of the existing metal roof panels, at least two fasteners that penetrate the L-shaped side through the existing metal roof panels and into the at least one roof perlins, a layer of adhesive on the substantially flat top portion of the roof furring; and at least one new metal roof panel on top of the layer of adhesive. There is also a new roofing system at least two roof perlins having a bottom portion attached to a roof deck by fasteners and a top portion, a layer of adhesive attached to the top portion of the at least two roof perlins and a metal roofing panel on top of the layer of adhesive attached to the top portion of the at least two roof perlins.

A protected membrane roof system for installation on a roof decking comprising an upper insulation board having an upwardly-facing upper board top surface and an opposite downwardly-facing upper board bottom surface and at least one through-hole communicating therebetween, a ballast material positioned over the upper insulation board, a netting positioned over the ballast material, and at least one fastener assembly having a base seated substantially adjacent the upper board bottom surface, a rod extending substantially vertically from the base of sufficient size so as to extend through the through-hole of the upper insulation board, the ballast material, and the netting, and a cap engaged with the rod above the netting, whereby the wind uplift resistance of the protected membrane roof system is improved and scour of the ballast material is reduced by effectively anchoring the netting to the upper insulation board beneath the ballast material.