If you are looking for a good type of wood to use for construction around the home, both oak and alder are good options to consider. That said, these two materials do have some major differences between them that you need to be aware of, and this is exactly what we are here to discuss today.
Let’s get to it and determine whether oak or alder is the more suitable choice for your next project.
What Is Oak?
We first have the oak tree, which is a hardwood deciduous tree that grows in the northern hemisphere, particularly in Europe, North America, North Africa, and Asia. In North America, there are over 160 types of oak trees, and today we are talking about the red oak, as it is one of the most commonly found and used for construction.
Oak is a fairly hard, heavy, and dense type of hardwood, which does make it very resistant to physical damage and quite durable overall. Furthermore, it also has great strength and is structurally sound.
On that note, because it does contain some natural resins and oils, it does allow for great moisture and fungus resistance. In terms of moisture, although it’s not the best choice for outdoor purposes, it can hold its own for quite some time. That said, oak is not overly pest-resistant.
This wood has a tight and straight grain, although it does have an uneven and coarse texture, along with a lot of knots and gaps. Oak is usually beige to brownish-red in color and is most often used for interior and exterior doors, cabinets, flooring, furniture, decorative pieces, and more.
What Is Alder?
We then have the alder tree, which can be found all throughout the northern temperate zone, particularly in northern Europe, North America, and northern Asia.
There are over 35 different species that can be found throughout the world, but one of the most commonly used and found in North America is red alder, so this is what we’ll focus on today. This tree can grow up to 100’ high and is most commonly found on the western coast of North America.
Alder is technically a type of hardwood, although it is one of the softest kinds out there. In terms of hardness, durability, and structurally soundness, it doesn’t rank very high. It’s also not very resistant to decay, pets, or moisture. It’s not the type of wood that you want to use for major structural applications or for outdoor use.
It works well for indoor purposes, especially because it is quite effective, it looks decent, and it is most often used for wooden toys, very low-end furniture, cabinets, decorative veneers, and crafts. It has a straight grain with a uniform and smooth texture, as well as a reddish-brown color.
Oak vs. Alder: What Are the Differences?
Now that we know what both oak and alder are, let’s figure out what makes these two different from each other.
Hardness
One of the biggest differences here is that alder is much softer than oak. Alder comes in at just 590 lbf on the Janka hardness scale, whereas oak comes in at 1,220 lbf. Therefore, oak is more than twice as hard and is much more physically resistant to denting, scratching, and other such types of damage.
Density
Red alder is a fairly lightweight type of wood, as it comes in at just 28 lbs per cubic foot, whereas oak is much heavier, coming in at 43 lbs per cubic foot. As you can see, oak is significantly heavier, which does contribute to its increased durability, but it does also make it harder to work with.
Pest and Moisture Resistance
The one thing that does need to be noted here is that red alder is just not very durable in terms of outdoor use. It’s not resistant to temperature changes, moisture or decay, or to fungus and pests. It’s just not ideal for outdoor use. On that note, oak is also not very resistant to pets at all, although it does a little better with moisture.
Although both are not ideal, if we had to choose one to use outdoors, oak would be it.
Overall Strength
If we are talking about things like compressive strength, the modulus of rupture, and the modulus of elasticity, oak scores higher on all three fronts. It’s just a more durable and structurally sound type of wood.
Workability
Because oak has more knots, is heavier, harder, and denser, it is also a little bit harder to work with. It just takes more effort to saw, screw, and paint it. That said, it’s not like either is very difficult to work with.
Appearance – Color and Grain
What is interesting to note is that both of these types of wood have a fairly similar appearance, although oak tends to be a little more reddish than brown, whereas alder is a bit browner than red. Most people would agree that oak is definitely the better-looking of the two.
Cost
Alder is one of the most cost-effective types of wood out there, and it’s only going to cost around $5 per board foot, whereas red oak can cost up to $25 per board foot.
When to Use Oak?
If you need a type of wood that is extremely durable, hard, and structurally sound, as well as good-looking, particularly for indoor purposes, then oak is a great option. This is true whether we are talking about floors, walls, doors, cabinets, or anything in between.
When to Use Alder?
If you are looking for an extremely inexpensive type of wood that looks decent and works well for basic utilitarian purposes, then alder makes for a fine option. Things like decorative pieces, veneer, low-end furniture, and more, are all prime candidates for this material.
Alternatives to Oak and Alder
As you could probably guess, neither of these types of wood is particularly ideal for outdoor use. If you need a fairly inexpensive alternative that works well outdoors, one of the best options to consider is red cedar. This wood is fairly durable, can be structurally sound under the right circumstances, and is one of the best options for outdoor purposes.
Summary
As you can see, alder is a fine option if you need something basic for indoor purposes that won’t cost you much. Although, if you need something durable, structurally sound, and something that may be ideal for outdoor use, oak is the better option.