Advice: Comparing British and Canadian cedar cladding
We often get asked about the difference between British grown and Canadian grown western red cedar. In this short video I’m going to do my best to answer that questions.
Western red cedar is the common name given to the tree Thuja plicata. Western red cedar predominantly grows in Canada and north America but it does also grow in Britain, in commercial quantities. And we’re often asked about the difference between these 2 cousins. Canadian western red cedar is a darker cedar, darker in colour and does include a wide variety of colours within the batch. But it is relatively knot free, you do get the occasional knots, but not many.
British western red cedar, on the other hand, is paler in colour, more consistent in colour as well. But it is a much more knotty cedar. You’ll see on this sample board here many, many knots.
Canadian western red cedar is much more dense than the British grown western red cedar and we can see that if we look at the end grain of these sample pieces, you can see here the British western red cedar, the growth rings are quite far apart. Whereas for this pieces of Canadian western red cedar you can see these growth rings are actually very very close together. And this indicates that it’s a much denser piece of timber.
This is not so important for cladding, but if you were to use cedar for other uses such as decking, construction or joinery we certainly wouldn’t recommend that you use British cedar because it’s just too weak.
Durability wise both of these types of cedar are classed as durable and you should get a service life of 30 years and more from both of these.
As far as the grading goes for these two type of cedar, the Canadian cedar is actually imported into the country under a rather complicated sounding grade of number two, clear and better, including 15 percent fourths. On some occasions it is sold on this grade but we actually like to use the BS and EN standards because they’re more consistent across all the species. The BS standard, the applicable standard is 1186-3, but this has officially been superseded by the European standard EN942.
British western red cedar on the other hand is actually on the whole too knotty to be able to use any of the recognised standards so we just simply describe this as “knotty cedar”.
It terms of the weathering, one of the drawbacks of Canadian cedar is that it does have a very wide variety of colours and this can result in quite a patchy look while the cedar is actually weathering. Additionally the Canadian cedar does include a lot of brown oil, which is what actually makes it durable, but this will leach out during the early months while weathering. This can lead to staining on the boards and it can actually lead to staining on any materials that are beneath the boards, such as porous stone. This oil also reacts with anything ferrous, so certainly all metal work must be stainless steel but in polluted areas Canadian cedar can go quite black.
British cedar on the other hand tends to be a lighter pink in colour but it’s a more even colour, a more consistent colour, and it does tend to weather more evenly, certainly in the early months, and you do tend to get a nice consistent silvery colour across the boards. It’s also less reactive with ferrous compounds but you should still make sure that you use stainless steel.
I suppose the most important element is that the British western red cedar is 25% cheaper, in general, than the Canadian western red cedar.
In summary, Canadian western red cedar is darker in colour, but less consistent. It’s less knotty, it’s stronger and it is gradable. British western red cedar has a more consistent colouring, weathers more evenly and is cheaper. But I suppose that the key difference between the two is that British cedar is much more knotty than the Canadian cedar.
Thank you for watching.