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Choosing the right structural timber for each part of your build is important. The wood doesn't just have to form a load-bearing structure; it also has to last for as long as possible. When it comes to joists, it may pay you to use a kiln-dried hardwood.

What are the benefits of using this type of wood?

1. Better Strength

Some timbers are stronger than others. This is partly down to a wood's natural properties; however, preparation methods also play a part in the final strength. Some woods come out of their production process in a less-than-perfect condition.

For example, some production techniques involve drying timber out in the sun or air.  While this works, it exposes wood to the elements. Heat, moisture and humidity can all have adverse effects on the timber, making it lose some of its internal stability.

It's easier to control the drying process in a kiln. Wood typically dries out faster. It also stays as strong as possible, as it isn't affected by external conditions. This strength makes the wood more robust and able to cope with being drilled, nailed and screwed into place.

2. Better Stability

When you use wood to build joists, the timber performs well to start with, but it may not stay as stable as time passes. If some wood has lost some of its dimensional stability in the past, then it might be more prone to shrinking and warping. This can affect the wood's ability to do its job.

If you use a kiln-dried hardwood, then the final timber you get is usually harder than the norm. It is less likely to change shape or position in the future. This makes it last longer.

3. Better Damage Resistance

Wood shouldn't just stand the test of time in itself. It also needs to be able to withstand certain types of damage, like fire and termite infestations.

While a treated timber helps with this, kiln-dried products may edge out other alternatives. The drying process itself kills any bugs that might be in the natural wood. The timber also becomes mould resistant. This helps prevent the wood decaying and attracting insects.

It is important to choose the right grade of kiln-dried hardwood timber for the job. Some grades are less suited to joist work than others; some have more fire and termite resistance.

To find a structural timber grade that fits your needs, ask your timber products supplier for advice.