Revision context
Document record
The file is a four-page technical guide, revision 0.1, dated September 2026, for a twin-skin insulated metal roof. It describes a site-assembled roof with a steel liner, an adaptable insulation zone and a separate metal weather sheet, with an illustrative exploded view that is not to scale. The guide describes itself as a concept guide, not a construction specification or a tested or listed assembly.
Page two covers the four layers: an outer R-panel weather sheet, engineered spacer rails and legs, a loose-laid fiberglass blanket, and a sealed R-panel liner. It includes a liner sealing table that sets design intent against US procurement candidates for side laps, end laps and profile closures. Candidate products named are Alpha Q131 tape, SFS metal-panel butyl tape and R-panel closures, and SikaLastomer-511 concealed-joint mastic.
Page three gives nominal insulation-only options from 5 in. to 16 in. thick, with US R-values from 16 to 50 and RSI and U-values in both unit systems. The basis is Knauf Performance+ metal building cavity insulation, with multilayer options calculated rather than tested. The guide states that steel legs, rails and fixings add heat-flow paths, so nominal blanket R-values cannot be used as the roof rating.
Page four covers fire performance. The unfaced fiberglass has documented ASTM E136 noncombustibility, a material property rather than an hourly roof rating, and no assembly fire rating is claimed. It lists heat flow, humidity, wind uplift, storm exposure and the condition of supporting steel as design factors, and ends with six numbered sources.
Material changes / notes
TCR-authored client guide, publication requested by the owner. Original illustration and explanatory content. Nominal insulation values do not establish whole-roof performance. This concept is not a construction specification, tested assembly or Euroclad product.