SBS Expansion Joint (Wall)

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SBS Expansion Joint (Wall)

Division D - Construction Details

SBS | Expansion Joint (Wall) ( Article

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Images used in a Construction Detail are representative and not prescriptive, and are not necessarily drawn to scale. They are intended to support the related Standard (Ref. Division A, Article

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SBS Details

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(1) Air or Vapour Control Layers
The requirement for a vapour retarder is determined by the design authority. Optional terminations.
(2) Insulation
(3) Insulation Overlay
Where required.
(4) Primary Membrane and Membrane Protection
(5) Membrane Flashing
Mechanically fasten to top of wood blocking.
(6) Membrane Counter-flashing
Flashing sealed to wall with compatible mastic.
(7) Metal Base Flashing
Mechanically fasten to top of wood blocking (C). Optional on flexible membrane systems. Required on assemblies using gravel ballast filter mats.
(8) Metal Counter-flashing
Into reglet approximately 30 mm (1¼") and caulked.
(9) Caulking
(10) Membrane Underlay
Minimum self-adhered modified bitumen membrane.
(11) Metal Cap Flashing
Must overlap exterior wall finish. Fasten with continuous concealed clip-type fasteners or cladding screws evenly spaced between seams.


(A) Acceptable Supporting Deck Structure
(B) Air and Vapour Control Layer Seal
Sealed to wall.
(C) Wood Blocking
Height to provide minimum 200 mm (8") above completed roof system, slope top edge.
(D) Flexible Insulation
(E) Reglet
(F) Sloped Wood Blocking

NOTE: See the Standard for additional requirements.

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