Frequently Asked Questions

What is C24 timber?

C24 is a grade of timber used to denote its structural integrity. Taking 50% longer to grow than C16 timber, it contains more growth rings which means it has a greater overall density. This greater overall density means that it is far more durable and stable. This sturdy constitution has made it a popular choice for structural purposes like exterior walls, decking subframes, balconies and even pedestrian bridges. At Suffolk Timber Supplies, our premium C24 timber carcassing is one of our most popular products.    

How strong is c24 timber?

C24 is often referred to as structural grade timber so it is one of the strongest gradings available to buy before you get into the realm of specialised timber products. Stronger than C16 timber, it can handle heavier loads which makes it an ideal choice for decking subframes and timber frame construction.


An example of a timber frame building, clad with beautiful Cedar

What’s the best timber to use outside?

It depends on the nature of the job, but the most critical aspect of timber for use outdoors is to ensure that it is properly treated to withstand appropriate weather conditions. This will naturally vary from job to job - the best timber for your shed panels might not be the best timber for your roofing, for example. If you’re unsure which timber will be best for your project, get in touch with a member of our team to get all the answers and supplies you require.

What is the most rot resistant wood?

Typically the most rot resistant wood, historically would have been treated with a tar based substance, however in respect of EU guidelines harmful products such as this are no longer able to be used. We find Oak to be a very weather resistant product, however all timber will deteriorate unless it is treated and dependent on how it is being used. For example, timber that is in constant contact with soil and moisture will deteriorate more rapidly than timber that is kept away from these elements.

How do you treat outdoor timber?

How you treat outdoor timber will depend entirely on the type of timber you’re using. Typically there are two options, timber is either dipped or pressure treated injected during manufacture, followed by stain/preservative once constructed. To ensure that you’re applying the correct treatment for your timber, be sure to check in with our team who will be happy to provide you with the best solution to guarantee a lasting finish.

How far can timber joists span?

This depends on a number of factors including the load the timber needs to support. Typically, we sell timber up to 6.0m in length. Depending on the project an architect or structural engineer will provide guidance. 

Which is stronger C16 or C24 timber?

C24 timber is a higher grade structural timber than C16 timber, that means it is the stronger of the two. Achieving a higher standard of timber is only possible in climates that force slower growth which leads to a tighter grain. At Suffolk Timber Supplies, we pride ourselves on only ever importing the very best of the best. 


Is treated timber waterproof?

No. As a natural product, timber will absorb moisture over time. It is, however, possible to slow this process through the proper use of timber products including high grade stains and oils. This is a very important thing to remember when planning any outdoor project that requires timber.

What wood lasts the longest outside?

It depends on where and how timber is used and what level of treatment and ongoing maintenance it will receive. There are, however, many hardwoods that if properly cared for will have a long exterior life. Feel free to give us a call if you’re planning to use wood outside and want to use one that will keep its good looks when it goes up against the elements.

Is timber frame better than block?

It is invariably quicker and more cost-effective to use timber framing rather than traditional concrete blocks when constructing a new building. This is naturally a huge advantage when it comes to planning and budgeting for a project. However, the best material for the job will always depend on the purpose of the building in question and normally a combination of the two is used. As timber merchants we are, of course, highly biased towards timber!