Timber products
Hardwood glulam beams and posts, straight and curved
Merbau and other hardwoods, laminated to your list and shipped to any port worldwide.
Made for exposed timber structures.
Glulam (glue laminated timber) bonds graded, kiln-dried hardwood boards into one large member. We supply beams, posts, rafters and portal frame members in merbau (kwila) and other hardwoods, for alfresco, pavilion, resort and public buildings.
Why hardwood
Chosen where the timber is seen
Most glulam is softwood. Hardwood is chosen when the timber will be seen and exposed.
- Denser and stronger, so a beam can often be smaller in section for the same load
- Slimmer, cleaner lines
- Durable species stand up to weather far better than pine or spruce
A solid hardwood beam of six metres or more is hard to find, very heavy and likely to split as it dries. Glulam avoids this. Graded, finger-jointed boards are bonded under pressure with exterior-grade structural adhesive, spreading natural defects through the section.
Long spans
Members of up to about 11.5 metres fit in a standard 40-foot container.
Stays straight
Seasoned laminations keep beams true, with little twisting, cupping or splitting.
Ready to fix
Notched and drilled at the factory, so it goes together quickly on site.
Technical data
Hardwood glulam species
| Species | Botanical name | Origin | Density at 12% MC | Durability and character | Best for |
|---|---|---|---|---|---|
| Iroko | Milicia excelsa, M. regia | West and Central Africa | about 640 kg/m³ | Very durable to durable (EN 350 Class 1 to 2). Golden brown, darkens with age | Exposed frames and feature beams |
| Merbau | Intsia spp. | Indonesia, Malaysia, PNG | about 830 to 860 kg/m³ | Class 1 above ground (AS 5604). Dark red-brown, very stable | Alfresco, pergola and pavilion structures |
| Yellow balau | Shorea spp. | Malaysia, Indonesia | about 900 kg/m³ | Very hard, yellow-brown. Durability class on request | Exposed exterior beams and posts |
| Okan | Cylicodiscus gabunensis | West and Central Africa | about 910 kg/m³ | Very durable (EN 350 Class 1). Dense, olive to red-brown | Heavy exposed and marine-side structures |
| Tali | Erythrophleum spp. | West and Central Africa | about 910 kg/m³ | Very durable (EN 350 Class 1). Dense and strong | Heavy structures, piers and shelters |
| Sapelli | Entandrophragma cylindricum | Central Africa | about 690 kg/m³ | Moderately durable (EN 350 Class 3). Reddish brown with a ribbon figure | Covered and interior feature beams |
| Eucalyptus | Eucalyptus spp. | Plantation grown, origin varies | Varies by species | Durability depends on species. Pale to pinkish brown | Economical structural members, coated or treated outdoors |
Typical published values for the solid timber of each species, as a guide. Durability applies to heartwood. Red balau is a different, much less durable timber, so we use yellow balau for exterior glulam.
Other tropical hardwoods can be laminated on request. Availability changes by season and manufacturer, so we confirm the species that suits your section sizes.
Where it is used
Typical projects
- Alfresco, pergola and verandah beams
- Pavilion and shelter frames
- Resort, villa and restaurant roof structures
- Warehouse, public, education and sports buildings
- Curved and feature beams
Straight, curved and tapered members
Curved and arched hardwood glulam is made for us in Malaysia, alongside straight and tapered members. Glulam is built from thin layers, so it can follow almost any curve. The tighter the radius, the thinner the laminations and the more of them.
Curved rafters and feature beams for domes, arches and sweeping roofs are made from your drawings or your engineer’s design.
Manufacture
Machined and pre-fitted before shipping
Members are cut, notched and drilled to your cutting list, with slots and holes for steel plates, bolts and dowels. Connections can be concealed, with slotted-in plates and dowels or hidden hangers, or left exposed.
Larger structures can be trial assembled at the factory, shortening the programme and crane time on site.
Through our timber engineering partners, we can help with the timber engineering and shop drawings. Council and authority approvals stay with you and your designer. Your own builder or contractor installs the glulam, or we can provide project supervision and timber installation supervision, anywhere in the world.
The adhesive that holds it together
Dense tropical hardwoods are harder to glue than softwood, so the adhesive, surface preparation and pressing all matter.
- PRF (phenol-resorcinol-formaldehyde): the benchmark for exposed exterior members. Waterproof, resists boiling and long-term weathering, and gives the strongest and most durable structural bond, with a dark red-brown glue line.
- MUF (melamine-urea-formaldehyde): a pale glue line, for protected and interior members.
- PUR (one-component polyurethane): used particularly for deep sections.
Tell us the exposure of your project and we will confirm the adhesive on your order.
Specification
Supply details
| Beam widths | 90, 115, 135, 165 and 190 mm |
| Beam depths | 200 to 600 mm, and deeper by arrangement |
| Posts | 135 x 135, 165 x 165 and 190 x 190 mm |
| Lengths | Up to about 11.5 m in a 40-foot container |
| Forms | Straight, curved, arched and tapered |
| Species | Iroko, merbau, yellow balau, okan, tali, sapelli and eucalyptus, and others on request |
| Laminations | Typically about 20 to 40 mm thick, thinner for tight curves, finger-jointed in length |
| Moisture content | Laminations kiln dried (KD) to about 8 to 15% before bonding |
| Adhesive | PRF for exposed exterior members. MUF or PUR where specified |
| Finish | Planed and sanded, then raw or coated |
| Machining | Notched, drilled and slotted to your cutting list |
| Packing | Wrapped and protected for sea freight, each member labelled to your drawing. ISPM 15 heat-treated and stamped bearers and dunnage on request, depending on the destination |
| Documents | Manufacturer’s strength data and test reports, CE marking where the manufacturer holds a European Technical Assessment, legality file, certificate of origin, phytosanitary certificate, packing list, and any fumigation or heat-treatment certificate the destination requires |
Strength and standards
Glulam strength classes explained
Every country labels glulam strength differently, and the labels are not interchangeable. A European GL 24h is not a weaker or stronger version of an Australian GL18; they measure different things. Your engineer chooses the class, and we supply the manufacturer’s tested values for it.
| Region and standard | Class names | What the label means | Examples |
|---|---|---|---|
| Europe, EN 14080 (glulam) | GL 20h to GL 32h (h homogeneous, c combined) | Characteristic bending strength in MPa | GL 24h: 24 MPa bending, stiffness about 11,500 MPa. GL 32h: 32 MPa, about 14,200 MPa |
| Europe, EN 338 (solid timber, used for hardwood laminations) | D24, D30, D40, D50, D60, D70 | Characteristic bending strength in MPa | D40: 40 MPa, stiffness about 13,000 MPa. D70: 70 MPa, about 20,000 MPa |
| Australia and New Zealand, AS/NZS 1328.1 (design to AS 1720.1) | GL8, GL10, GL12, GL13, GL17, GL18 | Named after stiffness, tested at a 300 mm reference depth | GL8: 19 MPa bending, stiffness 8,000 MPa. GL13: 33 MPa, 13,300 MPa. GL18: 50 MPa, 18,500 MPa |
| United States, ANSI A190.1 (hardwood species: AITC 119) | For example 20F-1.5E, 24F-1.8E, 26F-1.9E | Allowable bending stress F in psi, and stiffness E in millions of psi | 24F-1.8E: 2,400 psi (about 16.5 MPa) bending, 1.8 million psi (about 12.4 GPa) stiffness |
In Australia and New Zealand, glulam built to AS/NZS 1328.1 is the most direct route to meeting the National Construction Code or the NZ Building Code. Glulam made to another standard can still be used, but your certifier will want extra evidence, such as the manufacturer’s test reports and your engineer’s design calculations.
Standards, certification and documents
Most glulam product standards were written around softwood. Tropical hardwood glulam is normally verified by the manufacturer’s own testing (for example to EN 408), and your engineer designs to those declared strength values.
CE marking for hardwood glulam is possible where the manufacturer holds a European Technical Assessment. The scope depends on the manufacturer and the product.
Where certified timber is required, we source from FSC or PEFC certified mills and pass the mill’s certificates on to you. Sterling does not hold these certifications itself.
We collect the manufacturer’s documents and pass them on:
- Strength class and test data
- Mill certificates
- The legality file
- The packing list
Published structural data for hardwood glulam is less common than for softwood. Your engineer or certifier will confirm what evidence your project needs.
Process
Ordering and lead time
- Send your drawings or cutting list.
- We confirm species, sizes and price, and you approve the drawing.
- Manufacture and shipping: typically 4 to 8 weeks from confirmed order to your port, depending on requirements. Curved members, large sections and custom designs can take longer; we confirm the lead time on your quote.
- The glulam arrives at your port with certificates and shipping documents.
Tell us what you need. We reply within two working days.
Hardwood glulam FAQs
Can hardwood glulam be left exposed to the weather?
Yes, if it is a durable species, coated, and detailed to shed water. Seal the end grain, keep beams out of pooling water and choose yellow balau, okan, tali or merbau over sapelli where exposure is heavy.
Which adhesive is strongest?
Phenol-resorcinol-formaldehyde (PRF) is the strongest and most durable structural glulam adhesive, and it is the benchmark for exposed exterior members. Melamine and polyurethane adhesives are used where the glue line colour or the section depth calls for them.
How long can a beam be?
Up to about 11.5 metres, which is the practical limit for a 40-foot container. Longer spans can be spliced on site.
Can you make curved beams?
Yes. Curved and arched members are made in Malaysia from thin laminations bent to shape while the adhesive cures. Send the radius, section and span, and we will confirm what is practical in your chosen species.
Is CE certification available?
Yes, where the manufacturer holds a European Technical Assessment for hardwood glulam. The scope depends on the manufacturer and the product, and we confirm it with your quote.
How does hardwood glulam behave in a fire?
Large timber sections char on the outside at a predictable rate and keep their strength inside for longer than many people expect. Fire design is for your engineer, who allows for the charring in the section size.
Can you help with engineering?
Yes. Technical data and the manufacturer’s certificates are available on request, and through our timber engineering partners we can help with the timber engineering and shop drawings, or build to your own engineer’s design. Council and authority approvals stay with you and your designer.
Who installs the glulam?
Your own builder or contractor. If you want support, we can provide project supervision and timber installation supervision on site, anywhere in the world.
Who it’s for
Supplied to importers, builders and project teams
- Timber importers and distributors buying glulam by the container
- Builders and developers of homes, alfresco areas and commercial buildings
- Architects and engineers specifying exposed hardwood structures
- Hotel and resort projects
- Public and community buildings
Made to order to your sizes and drawings, shipped direct from the mill and quoted FOB, CFR or CIF. See how we work.
Related reading
Not sure which grade you need? Our guide to glulam strength classes sets Australian GL grades beside the European GL classes. For shipping terms on a container order, see FOB, CFR and CIF explained.
Send us your drawings
Tell us the sizes and quantities, and email your drawings or cutting list. We will come back with a price and a lead time.