Technical guide · Glue bond
In LVL, the glue line is the structure
A 45 mm EasiLVL beam is 18 veneers held together by 17 glue lines. If a bond lets go, the beam loses strength. That's why the Australian and New Zealand standards demand a Type A bond, and why we test it every two hours.
2.5 mm eucalyptus
17 glue lines
phenolic resin + bifenthrin Type A bond
AS/NZS 2754.1
Home / Technical guides / Glue bond
Bond types
Not all glue is equal
AS/NZS 2754.1 sorts the adhesives used in plywood and LVL into four bond types. Each is proven by a different water test. Only Type A has to survive boiling water, and only Type A is used for structural LVL.
| Type | Adhesive | Test the bond must survive | Typical use |
|---|---|---|---|
| A Ours | Phenol formaldehyde (PF) | 72 hours in boiling water, or 6 hours of steam at 200 kPa (about 132 °C) | Structural, permanent bond, boil-proof |
| B | Melamine urea formaldehyde (MUF) | 6 hours in boiling water | Limited weather exposure |
| C | Urea formaldehyde (UF) | 3 hours in water at 70 °C | Interior, occasional dampness |
| D | Extended urea formaldehyde | 16–24 hours in cold water, 15–20 °C | Interior, dry only |
A Type A bond won't delaminate when wet, but the wood itself still needs protection outdoors. Our products are for interior, dry use as supplied. Exterior use needs H3 treatment, coating and edge sealing by others.
In our lab
How we test a glue line
Every production batch is rigorously tested in our in-house lab. This is the glue-bond test from AS/NZS 2098.2, run on samples from current production approximately every two hours.
Cut
Specimens are cut from full-size beams straight off the line. At least 10 samples a day.
Steam
6 hours in an autoclave at 200 kPa steam pressure, about 132 °C. Weak bonds fail here.
Split
The chisel test: veneers are forced apart along the glue line within 24 hours.
Score
We rate how much wood fibre stays on the glue. When the wood breaks before the glue, the bond is sound.
Release
Daily minimum, maximum and average are recorded. No batch ships without lab sign-off.
Alongside the glue bond, the lab tests bending stiffness and strength on a calibrated 100 kN universal testing machine, and moisture content by the oven-dry method. BSI's February 2026 surveillance audit reviewed these records and recommended continued certification.
Before the test
A good bond is made, not found
Testing proves the bond. These controls create it. Each is measured and logged in our digital QC records for every glue batch or press load.
From a single approved supplier, TOA-Dovechem, with filler at a controlled mix ratio.
Checked on every glue batch, with a target of 3,000 cps.
The maximum deviation from target, weighed on full veneer sheets and checked for evenness.
Maximum final-stage temperature. Overheated veneer surfaces won't bond properly.
Tolerance around the press temperature the resin maker specifies, about 180 °C.
Panel pressure tolerance, with open and closed assembly times recorded.
Emissions
Super E0: the strictest in the world
All our products are Super E0 under the Australian and New Zealand standards: the strictest formaldehyde emission class in the world, together with Japan's F★★★★.
Phenolic resin cures in the hot press into a hard, stable bond. Once cured it releases very little formaldehyde, which means healthier air in the homes, schools and offices built with it.
Desiccator method, AS/NZS 2098.11. Japan's F★★★★ class sets the same 0.3 mg/L limit. PML result from independent characterisation testing of our LVL.
Every production batch is rigorously tested in our in-house lab
- Glue bondSteam, split and score, to AS/NZS 2098.2
- Bending stiffness & strengthOn our calibrated 100 kN universal testing machine
- Termite treatmentDosed into every glue batch. Read the guide
- Certified systemISO 9001:2015 and BSI Benchmark BMP 782420