SBS 2-Part Retrofit Flashing (Cable Penetration)

Jump to: navigation, search

SBS 2-Part Retrofit Flashing (Cable Penetration)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Division D - Construction Details

SBS | 2-Part Retrofit Flashing (Cable Penetration) ( Article

Notice to Reader
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

The reader may link to the related Article in the detail title, or link to the Standard as it relates to a specific element in the detail. All hyperlinks are displayed blue text.

SBS Details

SBS 2-Part Cable 1.jpg

SBS 2-Part Cable 2.jpg

Click below for a printable version of this page (under development)
Print Sheet


(1) Supporting Deck Overlay
Optional, depending upon deck condition and roof system requirements.
(2) Air or Vapour Control Layer
Installed following the requirements of Part 6 in this Standard. Tie in the control layers with membranes installed by other trades, to preserve continuity of the building enclosure (2a).
(3) Insulation
Installed in staggered and offset layers, and secured in accordance with the design of the system, which is based on the British Columbia Building Code, Part 4 and Part 5, and on Part 3 of the RoofStar Guarantee Standards for the membrane system type.
(4) Insulation Overlay
Subject to the requirements of Part 8 in the RoofStar Guarantee Standards for the membrane system type.
(5) Field Membrane (field)
Mechanically attached, torch-applied, adhered (shown) or self-adhered. See Tables 9.1 for acceptable membrane types and securement options. See 9.3 for application requirements.
(6) Two-part Penetration Cable Flashing
May be proprietary or shop-fabricated from galvanized sheet metal, consisting of two parts that are riveted together in the field, secured to the roof assembly and then ‘stripped’ into the field membrane to waterproof the flashing. This type of flashing may be adapted in its design to accommodate a pipe that turns horizontally to the roof field plane. The exit point for the penetration must be shielded with a hood and sloped downward to shed water. Secure separate lid with screw-type fasteners.
See 11.2.3 Curbs and Penetration Flashings for fabrication standards.
(7) Mastic
Applied to area receiving metal penetration flashing. See (12)(1).
(8) Base Membrane Flashing (target patch)
Cut from a single piece of self-adhering or torch-applied base membrane material, it is fashioned with a hole to fit around the penetration flashing and is sealed to the flashing and the roof field. The target patch must cover the flashing flange and extend beyond the edge of the flange, onto the field base membrane, by at least 100 mm (4”). See (12) for all applicable standards.
(9) Cap Membrane (field)
Granule-surfaced membrane. See Tables 9.1 and 9.2 for acceptable cap membrane types and their securement options. See 9.3 for application requirements.
(10)Cap Membrane (flashing)
Granule-surfaced membrane, installed following the standards published in Part 11.


(A) Acceptable Supporting Deck Structure
(B) Fibreglass insulation
Cavity fill, to inhibit condensation inside the flashing.

NOTE: See the Standard for additional requirements.

Back to "SBS" Roof System Details


© RCABC 2023
No reproduction of this material, in whole or in part, is lawful without the expressed permission of the RCABC.