Design Prolam Glulam to NZS AS 1720.1

Prolam glulam is integrated in SPEC Toolbox for design to NZS AS 1720.1:2022. Three grades are live in the platform database, GL8, GL10 and GL12, across 105 cross-sections from 42 by 88 mm to 300 by 595 mm, in Radiata Pine and Douglas Fir from the Upper Moutere factory. Sections wider than about 150 mm are block glued, to a maximum of 595 mm, and members run to 16 m. The beam, column, member design and beam penetration modules read the integrated section and grade set directly.

Prolam NZ manufactures glued laminated timber at Upper Moutere and supplies structural beams and posts into the New Zealand market. Radiata Pine and Douglas Fir laminations are bonded with a phenol resorcinol formaldehyde adhesive, and the range is offered untreated or treated to New Zealand hazard classes in both visual and non-visual grades.

Three GL grades are integrated: GL8, GL10 and GL12. Laminations are Radiata Pine and Douglas Fir, with lamella thickness from 28.5 mm to 50 mm.

The integrated cross-section set carries nine widths, 42, 63, 88, 112, 135, 180, 220, 260 and 300 mm, against depths from 88 mm to 595 mm, giving 105 width and depth combinations. At 42 mm width the depth range runs to 450 mm; from 63 mm width it runs to 595 mm. Single sections are produced to about 150 mm wide, and wider sections up to 595 mm are block glued. Maximum production length and maximum transport length are both 16 m.

Laminations are bonded with phenol resorcinol formaldehyde (Hexion R27). The declared charring rate is 0.675 mm/min. Chain of custody is FSC. CNC machining is available.

Surfaces are supplied as Visual Appearance A, where surface voids are filled and faces are planer machined for clear or painted finishes, or as Non-Visual Appearance C in H1.2 and H3.2, where machine skip, voids and loose knots are permitted. Bandsawn, preprimed and sanded and sealed finishes are also offered, each requiring sealing for long term protection.

Treatments are untreated, boron H1.2 for interior use, and MCA or CCA at H3.2 for exterior above ground and H5 for exterior and in-ground structural use. Treatments are available for both visual and non-visual grades.

Beams and columns. Interior use untreated or in boron H1.2. Exterior above ground use in MCA or CCA H3.2. Exterior and in-ground structural use in MCA or CCA H5. Visual and non-visual grades both accept treatment, and CNC machining is available for fabrication.

• Block gluing carries the section width from about 150 mm as a single section to 595 mm, and the integrated depth range reaches 595 mm as well, so wide and deep members come from the same grade set at lengths to 16 m.
• All 105 integrated cross-sections are available in each of GL8, GL10 and GL12, so a member can be moved up or down a grade without changing its geometry in the model.
• The bond line is phenol resorcinol formaldehyde (Hexion R27) rather than the melamine or polyurethane adhesives that are usual in the category.
• The treatment range extends to H5 in both MCA and CCA, covering in-ground structural use, and treatment is offered on visual as well as non-visual grades.

Prolam glulam appears in the member design modules: Timber beam, Timber column, Member design and Beam penetration. It also appears in the connection modules, in the screw connection module and in the CLT floor-to-glulam beam connection.

Member behaviour is taken from the integrated database for Prolam. The same database values are used for design to the Australian and New Zealand standards. Fire design, vibration and other verifications not covered by the design standard itself can be checked against other relevant documentation.

Design follows NZS AS 1720.1:2022, the New Zealand timber structures design standard, which superseded NZS 3603:1993 and is held in the platform reference library. The grades are recorded as produced to AS/NZS 1328, the Australian and New Zealand standard for glued laminated structural timber. This is a New Zealand product for the Australian and New Zealand market, so no European Technical Assessment applies and the product is not CE marked to EN 14080.