4x2 Timber Treated C24

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4x2 treated timber is a quality C24 graded timber that has been pressure-treated to prevent both fungal and insect attack. When it comes to timber, fungal and insect attacks are no joke. Insects can bore into timber, causing it to become structurally unsound; the damage of which is not only costly to repair but also a serious safety hazard. Thanks to the protective treatment of the timber, and its C24 grading, 47x100 treated timber can be used in many different indoor and outdoor applications. We supply various lengths: 2.4m, 3m, 3.6m, 4.2m, 4.8m and 6m

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What Is 4x2 Timber? 

4x2 C24 timber is a high-quality, strength-graded wood that is commonly used in structural applications where greater loads and stresses are anticipated. 

The "4x2" refers to the nominal dimensions of the timber in inches, translating to approximately 100mm x 50mm in metric measurements (with an approximate finished size of 45mm x 95mm). 

The designation "C24" indicates that the timber meets specific strength and quality standards, making it suitable for heavy-duty construction tasks.

While exceptionally well-suited for structural uses such as floor joists, roof rafters, and framing in construction projects, its robust nature also makes it ideal for outdoor projects like decking supports and pergolas where strength is a necessity.

What is 4x2 C24 Wood Used For?

  • Flooring
  • Roofing - rafters/joists in a loft floor
  • Walling
  • Decking joists - as it is able to bear heavier loads than ungraded timber (or that which is graded to a lower level such as C16.)
  • Carcassing timber in floor joists
  • Garden furniture and other outdoor projects 

4x2 Timber Benefits

  • Treated to resist rot, decay and insect attacks
  • Durable timber option, making it ideal for outdoor use
  • Treated nature deems it low-maintenance
  • You won't have to spend time and money regularly maintaining it

4x2 Timber Sizing Explained

4x2 treated timber is most often measured in inches, which is an imperial measurement, though it is sometimes measured in metric and this is where millimetres (mm) come into play. 

The sizing of 4x2 timber is considered to be either:

  • Nominal Size: 47mm x 100mm
  • Finished Size: 45mm x 95mm

This slight discrepancy is accounted for by the way the timber is cut and prepared. The difference in the two sizes is minuscule and should not make a meaningful difference to your project. At Materials Market, we sell the finished size (45mm x 95mm). 

4x2 Treated Timber - Treatment Process

There are a plethora of timber types on the market from treated, untreated and sawn carcassing timber. 

It is essential to use good quality treated timber for your construction projects as timber is usually located in places that are not easy to get to. This means we usually have no way of knowing if parts of the structure are under attack from insects or dampness, thereby weakening it.

C24 graded 4x2 treated timber has been pressure-treated to counteract both fungal and insect attack. 

Tanalith E is applied to 4x2 timber through a process called pressure treatment. During this process, timber is placed in a closed cylinder, and the Tanalith E solution is forced into the wood under high pressure. 

This method ensures deep penetration of the preservative, providing long-lasting protection throughout the entire piece of timber.

Tanalith E is a popular type of wood preservative used in the treatment of timber. It's a water-based solution that includes copper and triazole compounds as active ingredients. This preservative is highly effective at protecting wood from fungal decay, wood rot, and wood-boring insects. 

Frequently Asked 4x2 Questions

Can I Paint 4x2 Treated Timber?

Absolutely! Painting treated timber wood will not only help you achieve your ideal aesthetic but also gives the wood an additional layer of protection, which is something you want. When painting pressure-treated wood, however, you must be careful. 

Most 100mmx50mm timber is still “wet” and needs time for the chemicals permeating the wood to settle and dry. At this point, the wood is noticeably heavy and will still feel damp to the touch. 

If primer or paint is added to it at this point, there is every likelihood that it will be rejected by the water-based chemicals that are still working their way through the wood.

It is important to permit the timber to dry out fully before attempting to add paint or primer. This can be a lengthy process and may even take up to a few weeks depending on where the wood is stored. 

If there is too much heat and direct sunlight, this can cause the treated timber to warp instead of dry out. Damp conditions can also prolong the drying-out period. 

How Can I Tell if 4x2 Wood is Treated?

There are a few indicators that 4x2 timber has been pressure treated. The first is that it should be labelled as such with a stamp. However, when timber is cut to size, this occasionally gets removed.

Another tell is the colour of the timber; treated wood that is still relatively new should have a green tinge to it. This green hue fades over time and becomes honey gold before turning silver.

The smell can also be an indication, but this is only really effective when the wood is relatively fresh. New pressure-treated wood will carry a slight chemical smell, whereas non-treated wood won't. Again, this isn't a foolproof method and only works on freshly treated timber. 

What's The Difference Between 4x2 Treated Timber & 4x2 Sawn Timber?

4x2 Sawn timber is wood that has been cut to the required dimensions but hasn't yet been pressure treated and kiln dried. 4x2 Pressure-treated timber, otherwise known as tanalised timber, provides many benefits, such as resistance to the elements.

The goal of pressure treating wood is to force preservative chemicals deep into the timber's cellular structure. This pressure treatment process will often include copper and organic co-biocides, which help to repel both insects and moisture. 

Is 47x100 Treated Timber Environmentally Sustainable?

All of the timber lengths sold by Materials Market has been responsibly sourced.

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