Tanalised Treated Timber 47 x 100mm 3.0m – 4×2 Timber
Tanalised Treated Timber 47 x 100mm 3.0m is a versatile pressure-treated softwood section suitable for outdoor construction, landscaping and general building work. It is commonly referred to as 4×2 timber, based on its traditional approximate imperial dimensions of 4 inches by 2 inches.
The 47 x 100mm section is one of the most widely used timber sizes for general building and DIY projects. Its practical 3.0-metre length is straightforward to transport, store and handle while still providing enough material for many frameworks, supports and outdoor structures.
The timber has undergone a controlled pressure-treatment process to provide additional protection against fungal decay and wood-destroying insects. This improves its durability compared with untreated softwood when it is correctly specified, installed and maintained in a suitable environment.
Product dimensions
The nominal product dimensions are:
- Metric section: 47mm x 100mm
- Common imperial name: 4×2 timber
- Length: 3.0m
- Material: Treated softwood
- Treatment: Pressure treated or tanalised
- Suitable for: Building, landscaping and outdoor projects
The common name 4×2 is a traditional trade description rather than an exact imperial conversion. Use the stated metric dimensions when planning, measuring and cutting the timber.
What is tanalised timber?
Tanalised timber is softwood that has been treated with preservative using a controlled vacuum and pressure process. This allows the preservative to penetrate deeper into the wood than a standard surface coating.
The treatment helps protect the timber against fungal decay and attacks from wood-destroying insects. This makes treated timber a practical choice for many outdoor, exposed and moisture-prone applications.
Pressure treatment does not make the wood completely waterproof or maintenance-free. Exposure to moisture, sunlight and changing temperatures may still cause weathering, colour changes, natural movement and surface checking.
Cutting, drilling or notching the wood may expose internal areas that have not received the same level of preservative treatment. Coat all freshly exposed surfaces with a suitable end-grain wood preservative during installation.
Common uses for 4×2 treated timber
The 47 x 100mm section is a highly adaptable timber size that can be used across numerous construction, landscaping and garden projects.
Depending on its strength grade and the project specification, possible applications include:
- Outdoor timber frameworks
- Garden sheds and structures
- Landscaping projects
- Timber supports and bearers
- Garden screens and dividers
- Agricultural and equestrian projects
- Raised garden features
- External carpentry and joinery
- General repair and maintenance work
- Bespoke garden structures
- Load-bearing members where correctly graded
- Outdoor DIY projects
Where this timber will carry structural loads, confirm that it has the correct strength classification. Tanalised timber should not automatically be assumed to be C16 or C24 unless the product is specifically marked and sold with that grade.
The required span, load, support spacing and fixing arrangement should be confirmed by a suitably competent person where structural performance is necessary.
Benefits of the 3.0m length
The 3.0-metre length is a practical choice for many everyday building and landscaping jobs. It can be easier to transport, carry and store than longer 4.8m or 6.0m pieces.
It may be installed as a full length or cut into multiple smaller components. Preparing a cutting schedule before beginning work can reduce unnecessary waste and help make efficient use of the timber.
The weight of each length will vary depending on its moisture content. Appropriate handling procedures should still be followed when moving or carrying several pieces together.
Natural characteristics of timber
Timber is a natural product, so every piece will vary in grain, colour, knots and surface texture. These differences are expected and form part of the material’s natural appearance.
Knots, resin pockets, minor splits and surface checking may be present. These characteristics do not automatically indicate a defect, although their suitability will depend on the intended use and any applicable grading requirements.
Pressure treatment introduces moisture into the timber. As it dries, some natural shrinkage, twisting, bowing or cupping may occur. Correct storage, acclimatisation and installation can help manage this movement.
Newly treated timber may initially have a green or brown shade depending on the preservative system used. Its colour will generally fade and weather gradually following outdoor exposure.
Important sizing information
Please note: Timber dimensions are nominal and may vary slightly due to machining, pressure treatment, moisture content and the natural movement of the wood.
The common name 4×2 is an approximate imperial description rather than a guarantee of exact finished dimensions. If precise measurements are important, measure the timber before installation or contact us to confirm the current stock specification.
Allow the timber to acclimatise where appropriate before completing work involving precise joints or close-fitting sections.
Cutting and installation
Use suitable woodworking tools fitted with sharp blades when cutting or drilling this timber. Wear protective gloves, eye protection and suitable respiratory protection when handling, sawing or sanding treated wood.
Work in a well-ventilated area and avoid breathing timber dust. Sawdust and offcuts should be collected and disposed of responsibly. Pressure-treated timber should not be burned on domestic fires, in wood-burning appliances or on garden bonfires.
Apply a compatible end-grain preservative to every cut end, drilled hole and notch. Use corrosion-resistant fixings suitable for pressure-treated timber, particularly in external or regularly damp environments.
Where the timber forms part of a load-bearing structure, supports, connections and fixings should follow the approved design and be suitable for the anticipated loads.
Storage and maintenance
Store the timber flat, raised off the ground and supported at suitable intervals. Protect it from prolonged saturation while allowing sufficient airflow around the lengths.
For visible outdoor installations, a compatible oil, stain or protective coating may be applied once the timber has dried sufficiently. Follow the coating manufacturer’s instructions for surface preparation and moisture content.
Inspect external timber periodically, paying close attention to cut ends, joints, fixing points and areas where water may collect.
Key benefits
- Versatile 47 x 100mm timber section
- Commonly known as 4×2 timber
- Practical 3.0m length
- Pressure treated against decay and insects
- Suitable for outdoor frameworks and landscaping
- Useful for garden and agricultural structures
- Easier to transport and handle than longer lengths
- Can be cut for different project requirements
- More durable than untreated softwood
- Suitable for professional and DIY construction
Tanalised Treated Timber 47 x 100mm 3.0m – 4×2 Timber is a practical and adaptable choice for outdoor frameworks, landscaping and general building projects. Always confirm its exact dimensions, treatment level and strength grade against the requirements of the intended application before installation.
