Can you Use CLS Timber for Decking?

Reading time: 3 minutes

How to treat CLS timber for outside use

CLS timber can be used when installing garden decking, putting up fences, and constructing garden structures and storage buildings.

However, it is not recommended. If it is selected for your project, CLS timber should have been treated before it is used outside.

CLS timber is available in treated and untreated options. Pressure treating the material with preservatives will help protect it from damage caused by insects or rot. 

Remember that CLS timber is not waterproof either. So, water-repellent treatments should be applied to the material to better protect it from moisture.

Paint designed to block UV rays and sealers which work to maintain colour are also available to be used on CLS timber – effective for added protection and to decorate the material as well.

As CLS is a softwood, C24 grade CLS timber should be used for exterior project work. This is a stronger choice than C16 grade CLS timber, providing better load-bearing support when installing joists or decking boards around garden structures.

Key benefits of using CLS timber for decking

There is a bit of work needed to get CLS timber ready to be used outdoors then, but there are so many reasons why it could be a standout choice for your garden and landscaping projects.

Benefits which make CLS timber a good choice of wood for building work include:

• CLS timber is a strong, versatile and highly durable material, making it suitable for so many different construction projects. 
   

• The material is usually more affordable than other types of processed lumber, while still being a high-quality choice.
   

• CLS timber is kiln-dried, which keeps its moisture content low, the material stable, and the wood less at risk of twisting, warping or cracking.
   

• Consistent and uniform dimensions mean CLS timber is great for achieving accurate alignments and measurements, as well as reducing how much timber you waste during a project.
   

• The material has rounded edges and planed surfaces, so is safe to handle and ideal for creating an aesthetically pleasing finish.
   

• CLS timber has a smooth surface, which makes it simple to stain, treat or paint.

Be sure to read our complete guide to CLS timber if you’d like more information on using this material for general construction projects. 

Are you focused on carrying out work around a property’s exterior surroundings? Then head to our comprehensive gardens and landscaping advice hub to find more inspiration for transforming outside spaces into havens that property owners can enjoy all year round.