Glulam species; Why use Douglas fir?

Named after Scottish botanist and collector David Douglas after he sent the first seed from North America back to Britain in 1827, Douglas fir’s botanical name, Pseudotsuga menziesii, pays homage to Archibald Menzies, who discovered the tree in 1791. 

The name is somewhat misleading, as technically the Douglas tree (also referred to as Oregon pine, and Douglas spruce), is not actually a true fir as it is not a member of the Abies genus. 

When it comes to the manufacture of glulam, Douglas fir is probably the third most common timber used after spruce and larch, and at Buckland we tend to find this is the same. Here is a little more about Douglas fir you might be interested to know… 

Douglas Fir project Falkner House

Where does Douglas Fir come from? 

Douglas Fir is native to Western North America but is now a conifer commonly grown in the UK, France, Germany and North America.  

In the southwest it is the second most common conifer species behind spruce. We are lucky at Buckland to have a good local resource for it, which is one of the reasons why we use it for so many of our projects. 

How is Douglas Fir different to Larch? 

The Douglas Fir heartwood has a reddish pinkish and a light-coloured sapwood in appearance, which makes it very similar to European or UK grown larch. It is also similar to Larch in that the sapwood is classed as non-durable, and the heartwood is classed as moderately durable.  

The most distinctive difference between the two is the colour, as Larch is usually more of a pale yellow compared with the pinkish hues of Douglas Fir. If you want to get more technical, in Douglas wood the slope of grain is fairly straight with the light and darker colours differing in terms of hardness. It can also have some resin pockets in larger sizes which can make it more characterful, so it really depends on the look that appeals to you which you choose from that perspective. 

What are the differences between Douglas Fir varieties? 

The visual quality of the timber can be quite variable depending on its origin. The most reliable high quality Douglas fir comes from North America where very large trees are harvested – they tend to be much longer and refined with less knots.  

European can be knottier if the trees are younger, although locally in the southwest it is possible to source very clear straight grained Douglas fir. An example would be these trees belonging to Ralph Nicholson, although these are his pet trees and unlikely to become available for glulam production!  

Douglas Fir project Falkner House

Is Douglas Fir expensive? 

Generally speaking, the North American being of the highest quality is reflected in the cost. Usually, North American Douglas Fir can be three or four times the price of European timber.  

Buckland clients tend to opt for either European or UK Douglas Fir for their projects due to this price difference, but it isn’t always the case. You can see an example of North American Douglas Fir at Royal Holloway University, and French Douglas Fir at the more recently completed Clifford’s Tower project in York. 

The price relative to other species can be seen here using our glulam beam price calculator. 

 What are the benefits of using Douglas fir? 

It is more durable than the most common glulam species spruce, and the variation in colour and distinctive grain can be good for customers looking for a bit more ‘vivid’ characterful glulam. The North American Douglas quartersawn is some of the most attractive timber you can buy in our opinion. It is very popular in Japan. 

North American Douglas fir can be a particularly good option for house extensions for example where the volume of glulam is small, but the visual impact is high. The European Douglas can be well suited for glulam structures that have some exposure to the weather – for example, this house where the beams are partially exposed. 

Can Douglas fir be used outdoors? 

Yes. Douglas fir is a particularly stable wood. Its durability and natural resistance to rot and insects make it a good choice for outdoor projects, although usually, it will require treatment to ensure you protect the wood and extend its life as long as possible.  

If treated Douglas fir should last 30 years or more, untreated you’d be looking at around half that. We would recommend for glulam that can be used untreated outside it is best to use sapwood free Douglas fir.  

The overall longevity of Douglas fir depends on its treatment and maintenance in the long term. 

Read more about other timber species we use at Buckland.