Here we have explained a number of acronyms and jargon commonly used within the timber industry.



The three buttons on the side will direct you to more information about the technical and sustainable advantages of timber.


AF&PA (American Forest and Paper Association)

A North American based association for the forest and paper industry.


You can find more information about AF&PA here.

AHEC (American Hardwood Export Council)

An international trade association for the US hardwood industry, representing the committed US hardwood exporters and the major US hardwood product trade associations.


You can find more information about AHEC here



Now more commonly called DLT or Dowel Laminated Timber. Similar to CLT but using dowels rather than resin. Boards are layered vertically, horizontally and diagonally into panels with very dry beech wood dowels are driven through the layers to connect them. In place the dowels absorb residual moisture from the layers and swell up to powerfully connect single layers of wood into one massive thick block.


CAP (China Action Plan)

A UK government grant to help TTF members get verified legal timber from Chinese supplies, managed on our behalf by the Tropical Forest Trust.

Carcassing Timber

Timbers processed for use in structural applications. For example, roof timber, floor joists and studwork for partitioned walls.

CBPB (Cement-bonded particleboards)

A mixture of wood particles, Portland cement, and some additives. It is typically grey in colour and the durability is the most important factor.


The European Confederation of Woodworking Industries represents 22 European and national organisations from 16 countries. It is the body backing the interests of the whole industrial European wood sector.


You can find more information about the CEI-Bois here.

CE Marking

Ensures the product is in compliance with the CPR for its structural application.


Please visit the RPP Hub for more information about CE Marking.

Chain of Custody

Essentially a generic phrase for systems that allow for accurate traceability of wood through the supply chain back to the forest from whence it came.

CITES (Convention on International Trade in Endangered Species)

An international agreement between governments that aim is to ensure that international trade in specimens of wild animals and plants does not threaten their survival.


You can find more information about CITES here.

CLT (Cross Laminated Timber)

An engineered timber product made from glueing layers of solid-sawn lumber together. Each layer of boards is orientated perpendicular to adjacent layers and glued on the wide faces of each board, usually in a symmetric way so that the outer layers have the same orientation.


To find TTF Members supplying CLS Timber click here.

CPET (Central Point of Expertise on Timber)

The UK government’s reference point for all timber procurement in the public sector. Closed in 2016, the CPET advised the relevant government minister of timber procurement policy and provided advice and guidance to procurement officers.


You can find more information about CPET here.

CPI (Corruption Perception Index)

Produced by Transparency International to rate the levels of corruption in each country around the world.

CPR (Construction Products Regulation)

Requirement to declare performance characteristics, via CE Marking, in order to place timber or timber-based products on the UK and EU construction products markets.

CSR (Corporate Social Responsibility)

Behaviour and activities of businesses in terms of their contribution to achieving economic, social and environmental sustainability.


DEFRA (Department for the Environment, Food and Rural Affairs)

Responsible for safeguarding the UK’s natural environment, supporting world-leading food and farming industry, and sustaining a thriving rural economy.


You can find more information about DEFRA here.

DfID (Department for International Development)

The department leading the UK’s work to end extreme poverty. They tackle the global challenges of this time including poverty and disease, mass migration, insecurity and conflict.


You can find more information about DfID here.

Due Diligence Process

An organised series of steps under the EUTR to ensure companies meet the requirement that there is negligent risk for supplying illegal timber.


You can visit the RPP Hub for more information on the Due Diligence process.


EAC (Environmental Audit Committee)

A committee that considers the extent to which the policies and programmes of government departments and non-departmental public bodies contribute to environmental protection and sustainable development, and to audit their performance against sustainable development and environmental protection targets


You can find more information about the EAC here.

EOS (European Organisation of the Sawmill Industry)

A trade association representing the interests of the European sawmilling sector on an European and International level.


You can find more information about the EOS here.

ETTF (European Timber Trade Federation)

Promotes the interests of the timber trade across Europe, representing key national federations for importers, merchants and distributors.


You can find more information about the ETTF here.

Eurocode 5: Design of timber structures

Also know as BS EN 1995, this is a European standard that allows a designer to prove compliance with the requirements of the European Construction Product Regulation and national Building Regulations.

EUTR (EU Timber Regulations)

Regulations that aim for operators in Europe to stop placing illegally harvested timber and products derived from illegal timber on the EU market.



Particleboard in BS EN 309 and is in BS EN 15197 Wood-based panels. Specifications as containing at least 70% flax and can also contain other raw materials, such as particles of wood.

FLEGT (Forest Law Enforcement, Governance and Trade)

Established in 2003, it’s the EU Action Plan aiming to reduce illegal logging by strengthening sustainable and legal forest management, improving governance and promoting trade in legally produced timber.


You can find more information about FLEGT here.


Type of engineered wood product that is made out of wood fibres. Types of fibreboard (in order of increasing density) include HDF, MDF, and hardboard.

Forests Forever

TTF’s committee focused on sustainability and responsible sourcing issues.


Chemical constitution of glues used in the manufacturing of composite wood products. There are defined occupational exposure limits for formaldehyde and, therefore, its presence must be shown on the CE Marking as either E1 or E2.

FSC (Forest Stewardship Council)

An independent, non-governmental, not-for-profit organisation established to promote the responsible management of the world’s forests through independent third-party certification.


You can find more information about the FSC here.


GDPR (General Data Protection Regulation)

A regulation designed to strengthen and unify data protection for all individuals within the EU. It intends to harmonise data privacy laws across Europe, to protect and empower all EU citizens’ data privacy and to reshape the way organisations across the region approach data privacy.


You can find more information about the GDPR here.

GFTN (Global Forest Trade Network)

Compromises a network of timber producers, processors and exporters and importers set up by WWF to facilitate the responsible procurement of wood products using a stepwise approach to phase out wood from unknown, illegal or controversial sources. It also recommends that buying organisations should continuously increase the proportion of products from FSC-certified forests.


You can find more information about the GFTN here.


A timber product with excellent strength, stiffness and dimensional stability. Glulam is made from parallel solid timber sections, glued together under high pressure and is generally in a form of beams but may also be used as columns or other structural elements.

Grown In Britain (GIB)

A programme to create a new and stronger market pull for the array of products derived from UK woodlands and forests, develop private sector funding and harness the positive energy and feelings towards British woodlands and forests.


You can find more information about Grown in Britain here.



Timber derived from Non-Coniferous trees. Although they are generally more durable and stronger than Softwood, Hardwood must be used in the correct way and environment. There are two main types of hardwood: temperate and tropical. As with all wood species consideration must be given to the legality and sustainability of the wood products.



Type of engineered wood with an I-shaped cross section used in construction. It is a key component of a structural floor and may also be in the form of beams in roofs or elsewhere.


You can find TTF Members who supply I-Joists here.


Internationally recognised badge to allow the internally movement of wood packages and pallets.

ITTO (International Tropical Timber Organisation)

Intergovernmental organisation promoting the conservation and sustainable management, use and trade of tropical forest resources. Its members represent about 80% of the world’s tropical forests and 90% of the global tropical timber trade.


You can find more information about the ITTO here.



Component of a structural floor and, in terms of wood, may be formed of solid, or engineered wood, like metal-web beams or joists.


Kiln Dried

A process to reduce moisture content of wood to prevent decay and allows the use in dry environments. It is below 18% moisture content.


Lacey Act

Approved in 2018, it is the US law banning commerce in illegally sourced plants and their products—including timber, wood, and paper products.

LVL (Laminated Veneer Lumber)

An engineered wood product made from rotary-peeled veneers of solid timber glued to form continuous panels, similar to plywood. It is used for structural and non-structural purposes.


Machine Strength Grading

Uses equipment such as the Goldeneye 700.

MDF (Medium-Density Fibreboard)

An engineered wood product made from wood fibres combined with resin in a dry process to produce an economical wood-based panel.


You can find TTF Members who supply MDF here.


Chemical compound often used as an overlay for MDF and plywood. When it is combined with formaldehyde it forms a durable thermosetting plastic which is often used in a variety of materials and household objects.


You can find TTF Members who supply Melamine products here.

MLTV (Mandatory Legal Timber Validation)

One of the SGS’ legal variation schemes.

Modern Slavery Act

Approved in 2015, it is an act of the UK Parliament designed to tackle slavery in the UK and consolidates previous offences relating to trafficking and slavery. The Act imposes requirement from companies to ensure slavery doesn’t occur in their supply chain both nationally and internationally.

MTC (Malaysian Timber Council)

Established in 1992, it promotes the development and growth of the Malaysian timber industry.


You can find more information about the MTC here.

MTCS (Malaysian Timber Certification Scheme)

Certification system developed by the Malaysian Timber Certification Council (MTCC). MTCS started operation in 2001 as a voluntary national timber certification system.


You can find more information about the MTCS here.



Non-Governmental Organisation.


OLM (Origine et Legalite du Bois)

System based in Cameroon to verify the legality of timber sourcing.


You can find more information on the OLB here.

OSB (Oriented Strand Board)

An engineered wood product where slivers of wood are oriented and glued together.


You can find TTF Members who supply OSB here.


Panel Products (or Wood-based panels)

An engineered wood product  where strands of wood in specifies direct in order to give defined structural performance.


There are two different categories: OSB2 & OSB3.


An engineered wood product made from wood chips, often recycled, compressed together with resin to give a smooth, for structural and non-structural forms, and most the most important structural form is for flooring panels.


There are two main types of Particleboard – Chipboard and Cement Board.


You can click on the products to find TTF Members who supply Chipboard and Cement Boards.

PEFC (Programme for the Endorsement of Forest Certification)

An international, non-profit, NGO which promotes sustainable forest management through independent third-party certification.


You can find more information about the PEFC here.


An engineered wood product made  from thin piles that are glued together with adjacent layers having their wood grain rotated up to 90 degrees to one another. Plywood is manufactured from many different species and comes in many different forms with different durability, structural strength and performance.

Preservative Treated Timber

Timber that has gone through a treatment process to prolong the lifespan of the wood.


Quality Assurance

Process to help give buyers confidence in the way a company operates and manufactures its products.



Traditional term used to describe wood from Pine trees. They are usually found in Scandinavia and Northern Europe.

RPP (Responsible Purchasing Policy)

A tool devised by the TTF to assist members in meeting the requirements of the EUTR, and prevent the likelihood of illegal wood entering the supply chain and requiring development of a plan to continually reduce that risk.


You can visit the RPP Hub for more information.


SFI (Sustainable Forestry Initiative)

North American certification scheme.


A multinational company headquartered in Geneva, Switzerland which provides inspection, verification, testing and certification services.


You can find more information about the SGS here.


Timber from coniferous, cone-bearing trees. They are the most commonly used timber because they offer good value and are readily available from sustainably managed forests. They are most commonly found in Scandinavia, Northern Russia., America and China.

SIPS (Structural Insulated Panels)

Panel with insulating foam core sandwiched between two structural facings, typically OSB. High performance building system for residential and light commercial construction.

Strength Grading

The process to assess and declare strength performance of individual pieces of wood. The most common grades for Softwood used in the UK are C16 and C24.


SVLK (Sistem Verificasi Legalitas Kayu)

It is the Indonesian timber legality assurance system ensuring wood and wood products are obtained or derived from originating sources and their management meets the legality aspect.


TFT (Tropical Forest Trust)

Business NGO that helps buyers and supplies trade in legal and sustainable tropical timber. TFT also manages the TTAP and CAP on behalf of the TTF.


You can find more information about the TFT here.

TLTV (Timber Legality and Traceability Verification)

One of SGS’ legality verification schemes 

TTAP (Timber Trade Action Plan)

Collaboration between the TTF and the Dutch and Belgian Timber Trade Federations with the EU to work with supplies in Asia, Africa, South American and China to improve their environmental performance. TTAP 1 = Asia and Africa; TTAP2 = China and South America.

TPP (Timber Procurement Policy)

The UK mandatory policy for timber procurement in the public sector. It applies to the government estate, including central government departments, executive agencies and non-departmental public bodies.


You can find more information about the TPP here.

Trussed Rafters

Pre-fractured structural element used to create structural frameworks of roofs.

Trussed Rafters Association

Association that’s the recognised mark of quality in trussed rafter roofs and metal web joists.


You can find more information about the Trussed Rafter Association here.


UKWAS (UK Woodland Assurance Scheme)

The UK’s certification scheme uniquely endorsed by both PEFC and FSC.


You can find more information about UKWAS here.

UV degradation

Degradation of the wood product due to exposure to light.


V Jointed

A common form of cladding profile where the exterior edges are removed during machining to form a v joint between two boards allowing rain or moisture to easily drain away.

Visual Strength Grading

Where trained staff visually inspect each piece on a production line in order to allocate the appropriate grade such as Special Structure (SS) or General Structure (GS). This requires staff undertaking a registered training course and then putting in place a factory production control system to ensure their output is consistent. Part of this process is that each grader must be audited at the factory each year to check their performance. Examples of UK companies who can provide training and auditing can be found below:


Find out more here.



Traditional term used to describe wood derived from Spruce trees. The are typically found in Scandinavia and Northern Europe.


You can find TTF Members who supply Whitewood here.

Wood For Good (WFG)

The UK’s wood promotion campaign. It works on behalf of the whole timber industry in the UK. It aims to promote the suitability and sustainability of wood as a building material to the construction and logistics sectors and associated professionals such as architects and design engineers.


You can find more information about Wood for Good here.

Wood Veneer

Thin slices of wood that are typically glued onto core panels to produce panelled wood, such as doors and cabinets.



One of the two types of transport tissue in trees, phloem being the other. The basic function of xylem is to transport water from roots to shoots and leaves.


Yellow Pine

More often known as Southern Yellow Pine is a strong and durable species from the southern states of the USA. Very amenable to preservative treatment this species makes a good choice for decking and outdoor structures.


You can find TTF Members who supply Southern Yellow Pine here.



The only wood starting with the letter Z and while prized for its distinctive stripped figure the species Microberlinia brazzavillensis is increasingly rare in the forests of Gabon and Cameroon and therefore careful consideration should be given before selection of this species.