(1) Wood roof sheathing and roof sheathing supports that do not conform to Articles 3.1.6.3. and 3.1.6.4. are permitted in a building or part of a building permitted to be of encapsulated mass timber construction, provided they are installed,
(a) above a concrete deck in accordance with Clauses 3.1.5.3. (2) (a) to (f), or
(b) above a deck of encapsulated mass timber construction, where,
(i) the deck is permitted to be encapsulated between the roof sheathing supports by a material or assembly of materials conforming to Sentence 3.1.6.4. (2) that provides an encapsulation rating of not less than 50 min,
(ii) the height of the roof space is not more than 1 m,
(iii) the roof space is divided into compartments by fire blocks in conformance with Article 3.1.11.5.,
(iv) openings through the deck other than for noncombustible roof drains and plumbing piping are protected by shafts constructed as fire separations having a fire-resistance rating not less than 1 h that extend from the deck to not less than 150 mm above the adjacent sheathing, and
(v) except as permitted by Subclause (iv), the roof space does not contain any building services.
(2) Combustible cant strips, roof curbs, nailing strips and similar components used in the installation of roofing are permitted on a building or part of a building permitted to be of encapsulated mass timber construction.
(3) Wood nailer facings to parapets that are not more than 610 mm high are permitted on a building or part of a building permitted to be of encapsulated mass timber construction, provided the facings and any roof membranes covering the facings are protected by sheet metal.