FAQs

Plywood panel — when ordered with Riga ECOlogical (EXT LN) bonding — is produced using 100% Riga ECOlogical adhesive. Riga ECOlogical is lignin-phenol-formaldehyde resin based glue, where part of the traditional fossil-based component (phenol) is replaced with lignin — a renewable natural polymer derived from wood. Also described in Product Data Sheets and Plywood Handbook page 48.

Although the adhesive used in Riga ECOlogical panels is partially based on renewable raw materials (lignin), the modification of the resin system does not change or affect the biodegradability of the plywood panel. The lignin-phenol-formaldehyde (LPF) adhesive is a thermosetting resin that provides the required strength, durability, and moisture resistance for exterior-grade plywood. These characteristics remain the same as in traditional phenolic-bonded panels, ensuring long-term performance and stability. Therefore, the product is not classified as biodegradable, and no biodegradability certification applies.

The use of lignin in the Riga ECOlogical adhesive formulation is currently limited by technical performance and processing requirements. While lignin is a renewable and sustainable raw material, it cannot yet fully replace all phenol components in phenol-formaldehyde resins without affecting key properties such as bonding strength, curing time, water resistance, and durability. For this reason, a balanced formulation is used — combining the environmental benefits of lignin with the proven reliability of phenolic chemistry — to ensure that the panels still meet EN 314 bonding requirements and EN 636 exterior-grade standards. Research and development are continuously ongoing in this field, and increasing the share of renewable components is a long-term goal. However, achieving a 100% bio-based adhesive that maintains the same mechanical and durability performance is not yet technically feasible at industrial scale.

Yes. The panels bonded with the Riga ECOlogical adhesive fully comply with the requirements for exterior (EN 314-2, Class 3) bonding quality.

The Riga ECOlogical adhesive is based on a lignin-phenol-formaldehyde (LPF) resin system. In this formulation, a portion of the fossil-based phenol in conventional phenol-formaldehyde (PF) resin is replaced with lignin, a natural polymer derived from wood — one of the main structural components of plant cell walls. There is also a brochure regarding Riga Ecological benefits regarding sustainability, reduced VOC and formaldehyde emissions, CO₂ storage etc. which could explain more advantages of using Riga ECOlogical.

The adhesive itself is not tested as a separate material, except to verify during production that its physical and chemical properties meet the requirements for plywood production. The performance evaluation is carried out on the final plywood panels bonded with the Riga ECOlogical (LPF) adhesive, in accordance with the Declaration of Performance (DoP) values and relevant European standards.

Additionally, all key product properties are regularly verified through our internal quality control procedures, ensuring stable and consistent performance across production batches.

There are no specific standardised long-term tests designed to evaluate adhesive bond durability over extended periods. Instead, the durability of plywood bonding is assessed through accelerated ageing tests, such as the wet and boiling tests defined in EN 314-1 and EN 314-2, which simulate long-term exposure to moisture and temperature variations. No additional long-term testing has been performed beyond these standard procedures.

However, since the Riga ECOlogical adhesive is a modification of a conventional phenol-formaldehyde (PF) system, its long-term stability is comparable to that of standard exterior-grade plywood. Phenolic adhesives are well known for their excellent ageing resistance, thermal stability, and durability under variable environmental conditions.

In addition, LPF resin systems have been used in our production for several years, and their performance has consistently proven reliable in both laboratory and real-life applications.

The Riga ECOlogical plywood panels are covered by the same warranty conditions as our standard exterior-grade plywood products. The product warranty covers manufacturing defects and ensures that the panels conform to the technical specifications and performance values stated in the Declaration of Performance (DoP) at the time of delivery.

As plywood is a natural wood-based product, its service life strongly depends on proper handling, installation, and exposure conditions. When used according to the intended purpose and relevant standards (such as EN 636-3 for exterior use), the panels demonstrate long-term durability comparable to conventional phenol-formaldehyde bonded plywood. Therefore, no separate warranty period is defined for the eco-modified version, as its performance and durability are equivalent to the standard product line.

No, the use of the Riga ECOlogical adhesive does not affect the Declaration of Performance (DoP) values of the product. The plywood bonded with the lignin-phenol-formaldehyde (LPF) resin meets the same performance criteria and classification as panels bonded with conventional phenol-formaldehyde adhesive, ensuring full conformity with EN 13986, including formaldehyde emissions and EN 636-3 S (structural use) and EN 636-3 NS (non-structural use) requirements.

The use of the Riga ECOlogical adhesive does not affect the production costs. However, the final price offered to the customer may depend on commercial terms and market conditions.