When it comes to construction, whether for household objects, furniture, or patios and decks, solid wood is always a good option to consider. However, there are of course many different kinds of lumber that you can use. Two very popular types include oak and spruce.
Today, we’re going to do a side-by-side comparison of both to see which one is better used for a variety of purposes.
What Is Oak?
First is oak, which is a deciduous hardwood tree. Today, we’re focusing specifically on the red oak, which is one of the most popular and commonly found types in North America. There are, however, over 160 different varieties of oak trees all throughout the Northern Hemisphere, mainly in North America, Northern Europe, North Africa, and Asia.
Oak is a fairly hard, heavy, and dense type of wood. It has good structural soundness, it’s resistant to physical damage, and it’s not easy to scratch or dent. It does also contain some natural oils and resins, which when combined with its density and hardness, make it somewhat moisture and fungus-resistant.
That said, it’s not the number one most moisture-resistant wood in the world, and if used outdoors, it should be properly treated and sealed first. On the other hand, keep in mind that oak is not at all resistant to pests.
In terms of appearance, oak features a brownish-red color with a very straight and tight grain, combined with an uneven and fairly coarse texture, and quite a few gaps and knots. This wood is most often used for purposes such as flooring, decorative pieces, cabinetry, furniture, and other interior projects.
What Is Spruce?
We then have the spruce tree, which is a type of coniferous evergreen tree that can be found in most boreal and temperate climates in the Northern Hemisphere, such as in North America, Asia, and Northern Europe. This is a softwood tree that can grow up to 200’ tall.
Spruce is somewhat dense and hard, and it can be somewhat resistant to physical damage such as denting and scratching. However, this wood is not very resistant to moisture, particularly over the long run. It doesn’t necessarily absorb moisture or decay very quickly but it will warp, shrink, and change shape. This material also isn’t very resistant to pests.
People do like spruce because it looks fairly nice, as it has a light reddish-brown color, combined with a straight grain, medium texture, and not very many knots or gaps. Spruce is generally used for joinery, trim, veneer, musical instruments, and other projects that don’t require a great deal of structural soundness.
Oak vs. Spruce: What Are the Differences?
Now that we know what both oak and spruce are, let’s figure out what makes these two types of wood different from each other.
One big difference is that oak is the much harder of these two trees. Oak comes in at 1,220 lbf on the Janka hardness scale, whereas spruce comes in at between 490 and 520 lbf. This means that this wood is effectively almost three times harder than spruce, therefore making it much more resilient to physical damage such as denting and scratching
Just like oak is much harder than spruce, it is also much denser. This wood has a density of 43 lbs per cubic foot, while spruce weighs about 28 lbs per cubic foot. This heavier weight does relate to oak’s increased durability, but it’s also much heavier and therefore harder to work with.
Pest and Moisture Resistance
One thing that can be said about both of these types of wood is that they are not very resistant to the elements. Now, neither of these materials is very resistant to pests at all.
Furthermore, both aren’t resistant to moisture and decay, although oak is more resilient than spruce on this front. However, both really aren’t ideal for outdoor use, especially when long-term exposure to moisture is concerned.
In a separate article, we dove deeper into oak’s water resistance (or lack thereof).
When it comes to other strength factors, such as the modulus of elasticity, the modulus of rupture, and compressive strength, oak scores much higher on all three fronts. It is just a much more durable, resilient, and structurally sound material.
Oak is much harder, heavier, and has many more gaps in it, which does make it significantly harder to work with than spruce, especially when it comes to sawing and screwing.
Appearance – Color and Grain
Oak is a little bit darker than spruce, slightly coarser, and has more irregularities, knots, and gaps. That said, many people would still say that oak looks a little better, mainly because of its rich reddish-brown color.
Oak is going to cost you up to $25 per board for it, whereas spruce usually won’t cost more than $7 per board foot. Spruce is absolutely the more cost-effective of these two types of wood.
When to Use Oak?
If you are looking for something that is highly durable, resilient to most forms of damage, and structurally sound, then oak is a fantastic option, especially for indoor purposes. You may use oak outdoors, although the wood has to be properly sealed, and it still shouldn’t be exposed to very high levels of moisture. Whether for walls, doors, cabinets, or furniture, oak is always a good option to consider.
When to Use Spruce?
If you are looking for a type of wood that is extremely cost-effective, durable enough for basic purposes, and fairly good looking too, then spruce is a decent option to consider. Its biggest selling point is that it just doesn’t cost very much, yet is still durable enough for basic indoor use. That said, we wouldn’t particularly use it for any furniture that needs to take a beating. Spruce also is not a good option for outdoor use.
Alternatives to Oak and Spruce
If you are looking for types of wood that are better for outdoor use, woods such as mahogany, teak, and cedar all make excellent choices.
Now that you know what the main differences between oak and spruce are, you can come to a decision about which one to use for your next woodworking project.