SBS Mechanical Equipment Curb

To read RoofStar Guarantee Standards for any element in this illustration, click on the blue-linked terms

(1) Gypsum Deck Overlay: Required when insulation is too thin to span flutes of steel decking or when required as thermal barrier by design authority.
(2) Vapour Retarder: If required by design authority.
(3) Insulation: Mechanically fastened. See available insulation products in the Accepted Materials section of this Manual.
(4) Insulation Overlay Board: As required.
(5) Base Sheet: Adhered to overlay board using asphalt, cold adhesive, self-adhered, mechanical attachment or torch applied according to manufacturer's specification. Torching directly to wood surfaces is not permitted.
(6) Base Sheet Flashing: Adhered according to manufacturer's specifications, using cold adhesive, hot asphalt, self-adhered or torch applied to cover boards, or mechanically attached membrane. Must be tucked under metal flange and mechanically attached to nailing strip.
(7) Cap Sheet: Applied according to manufacturer's printed instructions and to RoofStar Guarantee Standards.
(8) Cap Sheet Flashing: Applied according to manufacturer's printed instructions and to RoofStar Guarantee Standards. Must be tucked under metal flange and mechanically attached to the nailing strip.
(9) Metal Base Flashing: Mechanically fasten, standing seam at corners. Full width base flashing optional on flexible membranes. Partial skirt flashing minimum 75 mm (3") required on mechanical curbs that require flashing under metal flange.

(A) Acceptable Deck
(B) Air / Vapour Seal
(C) Mechanical Curb: Minimum 200 mm (8") and maximum 300 mm (12") above finished roof surface.
(D) Rigid Insulation

NOTE: Refer to RoofStar Guarantee Standards for additional requirements.

Some mechanical curbs are designed to allow membrane flashing to be carried up onto metal flange. Install according to manufacturers’ instructions.