If you are planning to build something out of solid lumber, then you have plenty of choices to consider. Of course, there are many different types of wood or trees out there, and finding the right one for specific purposes is essential. Two very popular types of wood include cedar and Douglas fir, both of which have their own special properties.
et’s figure out exactly what both cedar wood and Douglas fir are, what makes them different, and which one you should use for certain applications.
What Is Cedar?
First, we have cedar, which is a large coniferous or evergreen tree that can be found in the pacific northwest, both in Canada, and the USA. Although, there are some specific types of cedar trees that also grow in the Mediterranean and the western Himalayas. What is interesting to note is that what we commonly refer to as cedar wood is technically a part of the cypress family.
The trees we know to be cedar can get very large, up to 200’ tall with trunks measuring up to 13’ in diameter. Cedar is known for producing fragrant and durable timber with a reddish-brown color. Cedar is known for having few knots, being rot-resistant, stable, and has a beautiful grain. Cedarwood is often used for outdoor applications, such as decking, outdoor trim, siding, and outdoor furniture.
What Is Douglas Fir?
We then have Douglas fir, another type of coniferous or evergreen tree, one found in both eastern Asia and western North America. These trees can grow up to 250’ in height and usually top out at around 6’ in diameter. What is interesting to note is that both the coastal and rocky mountain varieties of Douglas fir are technically a part of the hemlock family.
Douglas fir is known for being very hard and durable, which is why it has many structural applications and marine uses. It’s often used for flooring, structural beams, and exterior siding, due to its high level of strength and durability. In terms of its appearance, it usually has an orange-reddish hue.
Cedar vs. Douglas Fir: What Are the Differences?
Now that we know what both cedar and Douglas fir are, let’s take a closer look at the main differences between them.
1. Durability and Hardness
One of the biggest differences between cedar and Douglas fir is durability. In terms of overall hardness, on the Janka hardness scale, Douglas fir comes in at 620. On the other hand, cedar comes in at just 350.
For those of you who don’t know, this means that Douglas fir is much harder than cedar. Although Douglas fir is not the hardest wood out there, it is still a bit harder than cedar.
With that being said, Douglas fir is also very flexible and durable. Even when it expands or contracts with moisture, its flexibility allows it to spring back to its original shape.
Douglas fir is also very dimensionally stable. Although cedar is also somewhat hard and durable, it is susceptible to accumulating dirt, mold, and mildew over time. If cedar is not regularly maintained, it will deteriorate over time. Simply put, Douglas fir is the much harder and stronger of the two.
The next difference to consider here has to do with appearance, with Douglas fir having very wide color variations, all the way from light yellow to reddish brown, which may differ between earlywood and latewood. Douglas fir also has a very distinct grain pattern that can differ according to how it is cut.
Moreover, Douglas fir also has a fine to medium texture, and most people say that it looks extremely nice.
On the other hand, we have cedar, which doesn’t have as much color differentiation, with some being reddish and others being pinkish brown. There may also be darker streaks present in the wood. Cedar also has a very coarse and straight grain with a natural and smooth luster.
3. Weather Resistance
When it comes to exterior use, both of these types of wood are ideal. That being said, cedar is the better of the two for long-term outdoor use, as it contains more natural oils than Douglas fir. Those natural oils act as a moisture barrier that helps to impregnate the wood and protect it from moisture.
For this reason, you’ll often see outdoor structures made of cedar that last for a very long time and don’t need that much maintenance. Sure, regular cleaning is required, but that is about it. It’s very resistant to rotting, and on that note, is also resistant to pests.
We then have Douglas Fir, which is also suitable for outdoor use, as long as it is treated first. Douglas fir does not contain that much natural oil, and although it is weather resistant, it’s not as resistant as cedar. It won’t last as long outdoors, will require extra maintenance, and needs to be cleaned regularly.
What is interesting to note about Douglas fir wood is that machining it and working with it, especially cutting it, is very easy, as it doesn’t suffer from much tear-out during the sawing process. That said, due to its hardness, Douglas fir does cause saw blades to dull fairly quickly. What people also like about Douglas fir is that due to its hardness, it’s also not easily damaged while being worked with.
Cedar is a bit different because it is much softer. It is also very easy to cut and work with. However, due to its softness, it is easily dented and scratched while being worked on. Cedar may be tough on the inside but has a soft exterior that requires a lot of caution when working with it.
What many people don’t consider is that these two types of wood also smell different, with Douglas having a resinous odor, more like tree sap than anything else, and cedar having more of an aromatic scent.
People tend to like both of these types of wood as they are moderately priced. That said, high-quality cedar is going to cost you more than Douglas fir. If we are talking about simple construction quality wood, then the price may be on par, but if you want the high-quality options, cedar will be the more expensive of the two.
When to Use Cedar Wood?
If you are planning on building posts, outdoor furniture, a deck, wood shingles, a boat, boxes, patio furniture, and crates, then cedar is the better option to go with.
When to Use Douglas Fir Wood?
If you plan on doing heavy construction, and you need wood that is hard, durable, solid, and structurally sound, then Douglas fir is the way to go.
Alternatives to Cedar and Douglas Fir Wood
If you are looking for wood that doesn’t cost too much, looks nice, smells good, and is moisture resistant, although not overly hard or durable, then pine is a good option to consider.
That said, both types of wood discussed today are softwoods. If you want hardwood that is as hard and durable as it gets, then ones such as maple, birch, red oak, white oak, and walnut are good options to consider.
Before making a decision, you might also want to read my comparisons of cedar with cypress, mahogany, pine, and redwood.
Now that you know what all of the major differences between cedar and Douglas fir are, and which ones excel at certain applications, you can make your own informed decision between them.