SBS Through-wall Scupper Drain

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SBS Through-wall Scupper Drain

Division D - Construction Details

SBS | Through-wall Scupper Drain ( Article

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SBS Details


(1) Air or Vapour Control Layers
If required by design authority.
(2) Insulation
See available insulation products in the Accepted Materials section of this Manual.
(3) Insulation Overlay
Where required.
(4) Primary Membrane and Membrane Protection
(5) Base Membrane Flashing
(6) Metal Scupper with Hopper
The outside face of scupper to be minimum 37.7mm (1½") lower than the box height with a 12.7mm (½") drip edge. Installed in a bed of compatible mastic. Interface between outside wall and scupper should be caulked with appropriate sealant. Installed when wall finish is complete prior to completion of roofing or sheet metal (e.g.: re-roofing).
(7) Mastic
Compatible with membrane
(8) Scupper Membrane Flashing
(9) Base Metal Flashing
Mechanically fastened (optional on flexible membrane systems).
(10)Metal Counter-flashing
Into reglet approximately 30 mm (1 ¼").


(A) Acceptable Supporting Deck Structure
(B) Air / Vapour Seal
(C) Wood Blocking
Optional with insulation cant strips.
(D) Plywood
If required by design authority. See the RoofStar Guarantee Standards.
(E) Wall Finish
Interface between outside wall and scupper to be caulked with appropriate sealant. Installed by trade responsible for outside wall finish if roofing and metal flashing has been completed prior to exterior wall finish.

NOTE: See the Standard for additional requirements.

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