What is the difference between Imported timber and Homegrown timber?
When it comes to choosing between Imported timber and Homegrown timber for your construction project, there are no major differences, just a few subtle ones which this blog will take you through.
Homegrown timber is grown right here in the UK; mostly in northern England, southern Scotland, western England and Wales. The trees grow quite quickly in our mild, rainy climate, thus producing softer timber. Homegrown timber is usually graded at what’s known as C16 strength grade.
Imported timber grows much more slowly, due to the colder climate in the Baltic states and Scandinavia.
Imported timber is often graded at C16 strength grade, but because of the slower growth time (as evidenced by growth rings present in the trees profile) it can make the higher C24 grade as well.
Homegrown timber is the most readily available, due to the fact that it doesn’t have to be shipped here. Imported timber tends to be slightly more expensive- not because it’s a superior product but because it’s in shorter supply. There are no identifiable structural differences in Homegrown and Imported timber at C16 grade.
C16 and C24 will generally achieve the same strength and stiffness in lengths of 5.4m or less. Longer lengths will fare better with the stronger grade (C24). This is where Imported timber becomes the only option as Homegrown trees are not capable of making that C24 grade. This is due to our faster growing conditions here in the UK.
Generally, the standard lengths; 3m, 3.6m, 4.2m, 4.8m and 5.4m in both C16 and C24 are interchangeable in purpose unless your architect or specifier has specified C24 grade for it’s superior strength capability.
There is also a question of choosing Imported treated or Imported untreated timber over the Homegrown counterparts. Treated timber usually goes through a process called “Tanalising” or “pressure treatment”. The timber is placed in a vacuum cylinder which is flooded with a preservative. The cylinder is then subjected to hydraulic pressure, which forces the preservative into the timber cells. This is why the treatment is sometimes called “pressure treatment”. Tanlith E. is a common preservative used in the pressure treatment process and has lent its name to the treatment as such, in a similar way that the brand name “hoover” has lent its name to vacuum cleaning. Again, these treatments are consistent between the Homegrown and Imported counterparts.
Treated timber is considered weather proof and suitable to use in external applications. Untreated timber needs to be treated with a finishing agent to stop it absorbing moisture and particles, especially when used in first fixing.
When it comes to choosing between Imported and Homegrown C16 timber for your construction project, the Homegrown option tends to be cheaper, more readily available and of course, it’s British. The Imported option is preferred where C24 grade is specified. Why not head over to our webpage and browse the full range of timber options using our easy-to-navigate menu options https://www.build4less.co.uk/Timber/