Timber Guide: CLS, MDF, Plywood & Treated Timber
What Is Timber? A Complete Guide to Timber and Sheet Materials
Timber is one of the most widely used building materials in the construction industry and has been used for centuries in everything from structural framing to interior finishing and furniture making. Today, timber remains a key material used by builders, carpenters, landscapers, and DIY users because it is strong, versatile, cost effective, and easy to work with. Whether you are building a house, constructing a garden project, or completing internal joinery work, timber is a material that is used in almost every type of construction project.
In simple terms, timber is wood that has been processed and prepared for use in construction or manufacturing. Once trees are harvested, the wood is cut, treated, and finished into usable sizes such as structural timber, battens, boards, and sheet materials. There are many different types of timber available, and each type is designed for a specific purpose. Some timber is used for structural work, some is used for roofing, some is used for internal stud walls, and other timber products such as sheet materials are used for flooring, furniture, and internal finishing.
If you are looking to purchase timber for your project, you can view a full range of options including structural timber, battens, and carcassing on our timber collection page.
Types of Timber Used in Construction
There are many different types of timber used in construction, and each one has a different purpose depending on where and how it will be used. The most common types of timber used in building include structural timber, CLS timber, treated timber, MDF board, and plywood. Each of these materials has different strengths and uses, which makes them suitable for different parts of a project.
Understanding the difference between these timber products will help you choose the right material for your job and ensure your project is completed to a high standard.
CLS Timber
CLS timber stands for Canadian Lumber Standard timber and is one of the most commonly used timbers for internal stud walls and framing. CLS timber is kiln dried and planed with eased edges, which means it has smooth rounded corners and is easy to handle and work with. It is mainly used for internal framing such as partition walls, stud walls, and boxing in.
Because CLS timber is kiln dried, it has a lower moisture content than regular timber, which means it is less likely to twist or warp after installation. This makes it ideal for internal structural work where straight and stable timber is important.
Example product: CLS Kiln Dried Timber 38x89mm
Treated Timber
Treated timber is timber that has been pressure treated with preservatives to protect it from rot, fungal decay, and insect attack. This makes it suitable for outdoor use and areas where timber may be exposed to moisture or damp conditions.
Treated timber is commonly used for roofing battens, fencing, landscaping, garden structures, decking frames, and external structural work. Because it is protected against moisture and decay, treated timber lasts much longer when used outside compared to untreated timber.
Example product: Green Treated Timber Batten
Sheet Timber Materials
In addition to structural timber, there are also sheet timber materials which are widely used in construction and joinery. The most common sheet timber materials are MDF board and plywood. These sheet materials are used for flooring, furniture, wall panelling, roofing, and many other applications.
MDF Board
MDF board stands for Medium Density Fibreboard and is made by compressing wood fibres together with resin to create a smooth, dense board. MDF is widely used for furniture, shelving, interior panelling, and joinery work because it has a smooth surface that is ideal for painting.
MDF is easy to cut and shape, which makes it very popular for interior projects and fitted furniture. However, MDF should generally be used in dry environments unless you are using moisture resistant MDF.
Example product: Standard MDF Sheet 2440 x 1220mm
Plywood
Plywood is made by gluing together thin layers of wood veneer, with each layer placed at right angles to the one below it. This makes plywood very strong and stable, which is why it is commonly used for flooring, roofing, hoarding, and structural boarding.
Plywood is stronger than MDF and is suitable for structural applications and areas where strength is important. It is commonly used for subfloors, roofing decks, and wall sheathing.
Example product: Hardwood Plywood 2440 x 1220mm
Why Timber Is So Popular in Construction
Timber is popular in construction because it is strong, lightweight, easy to cut, and easy to install. Compared to materials such as steel and concrete, timber is much easier to work with and requires fewer specialist tools. This makes it ideal for both professional builders and DIY users.
Timber is also a renewable material, which makes it a more environmentally friendly building material compared to many alternatives. When sourced from responsibly managed forests, timber is one of the most sustainable building materials available.
Common Uses for Timber
Timber is used in a wide range of construction applications including roof structures, floor joists, stud walls, fencing, decking frames, garden buildings, and internal joinery. Sheet materials such as MDF and plywood are used for flooring, furniture, and interior finishing.
Because timber is so versatile, it is one of the most commonly purchased building materials for both structural and non-structural applications.
Conclusion
Timber is one of the most important and widely used building materials in construction. From structural framing and roofing to internal joinery and furniture, timber products are used in almost every building project. Understanding the different types of timber available, including CLS timber, treated timber, MDF board, and plywood, will help you choose the right materials for your project.
If you are looking for high quality timber and sheet materials for your next project, you can browse the full range of products available at JJ Building Materials online and order directly for delivery to site.