Have you ever wondered why ancient people prefer to build monuments using stones? Look, for example, at the Great Pyramids of Giza, Stone Henge, or the ruins of Puma punku, and you will see that most extant ancient monuments were made of stones. But why did they prefer stones over wood? Of course, the reason is quite apparent, i.e., other materials like wood are susceptible to the effects of fire and moisture. Moisture, for example, is unforgiving. If you leave wood outdoors untreated, the wood will soon rot and disintegrate.
Whether you like it or not, natural wood will sooner or later succumb to the adverse effects of exposure to moisture and water. As such, you need to treat wood with paint or preservative to make them a bit impervious to the harmful effects of water and humidity. Nevertheless, there are almost water-resistant wood types, like Cedar, Juniper, and Teak. These wood species resist rot and insect infestations. For these reasons, many prefer these wood species for outdoor woodworking projects.
Classification of Wood Relative to Their Water-resistant Capability
As a meticulous woodworker, you will carefully consider beforehand whether your wood project will get exposed to moisture and water. If it gets will, it would be best to seal your wood using a water-resistant sealer or finish. You can also choose wood that is naturally resistant to water. Wood, however, is classified according to the following categories based on its level of resistance to water and moisture:
Category 1:
Wood species in this category are best for interior usage only. They get used in areas protected from the vicissitudes of weather. These wood species exhibit the least ability to resist moisture.
Category 2:
Wood species in these category can resist humidity of around 20% or more. These wood species, however, are still not recommended for use outdoors.
Category 3:
These wood species can accept humidity up to 20% or more. You can use these species for outdoor usage, provided they are not in direct contact with water or soil.
Category 4:
Wood species in this category exhibit outstanding resistance to moisture, and you can use these wood pieces in locations with direct contact with the water and soil. These wood species get often utilized for pontoons, posts, and fences.
Category 5:
These wood species exhibit the highest resistance to moisture and water. You can even dip them in water and still show excellent moisture resistance. They are tough and durable, and many get harvested from huge forests like the Amazon Jungle. They are also costly. These wood species get often used for decking timber and interior flooring timbers.
Wood Species That Are Highly Resistant to Water
After exposure to water and a strong acid bath for thirty days, wood would lose almost 70% of its strength. So, if you intend to leave wood projects outdoor, it will be best to use any of the following most highly water-resistant wood species available on the market today:
1) Teak
If you will invest money in making a piece of outdoor furniture or project using wood, your best option at hand, of course, is teak wood. Teak is native to tropical areas of Africa, Southeast Asia, and Latin America. It exhibits remarkable dimensional stability and durability, making it one of the best wood species for outdoor use.
Teak resists cracking and splitting caused by exposure to UV light, water, and moisture. Its color ranges from golden brown tones to reddish tones. It was used in shipbuilding even during the Middle Ages, and until now, shipbuilders still use it for ship and boat construction.
In the 1950s, teak got introduced in the U.S. and immediately became the preferred choice for outdoor wood projects.
Teak is weather-resistant, pest-resistant, low-maintenance, beautiful, and durable. These properties make teak an expensive option. You can use teak wood in water-exposed and susceptible areas like floors, foundation footers, pergolas, stairs, and decks.
2) Ipé
Wood experts dub Ipé one of the best tropical woods because it has sterling characteristics. Ipé, of course, is a wood name for some South American wood species. It is hefty and robust. It is also highly resistant to fungi that destroy wood. Besides, its dimensional stability is remarkable.
Ipé Lapacho is the only other wood that comes near the excellence of teak. It has a brown tone and comes with slight color variation. Its heartwood sports yellowish or dark brown tones with dark or light banded parts. Its sapwood is somewhat yellowish gray, and its fiber structure is very regular with straight and fine grain that sometimes interlock.
Ipé features a very dense wood that is around 1050 kg/m³ at twelve percent humidity. It is very dense that it will not float in water. Ipé also does not exude a characteristic smell.
Processing this wood with hand and machine tools would be a challenge. Thus, when nailing, it will be best to pre-drill holes. This wood is the perfect wood in areas highly exposed to water like bridges, railway sleepers, fenders, crosses, doors, decks, and windows.
3) Iroko
Another excellent wood is the Iroko. It is a tropical African wood that exhibits sterling durability. Its heartwood features medium brown to golden tones, and its sapwood features a pale yellow color. Iroko is known for its high-water resistance and sterling durability.
Iroko is rot-resistant and can withstand the vicissitudes of the weather. It is also very versatile, allowing for use in many areas. Moreover, Iroko is somewhat similar to teak wood in properties and appearance, and for this reason, it got dubbed the African teak. Thus, it is an excellent substitute for the teak, for it is less expensive than the teak.
If you’re looking for an ideal wood for the outdoors, Iroko should be on your list. It is also easy to work with and allows for an excellent finish. You can use it for carpentry, outdoor furniture, shipbuilding, railway sleepers, flooring, decking, and bridges.
4) Pink Peroba Wood
One of the most commercially valuable timber trees is the Pink Peroba or Peroba Rosa. It is a noble wood that you can use in areas exposed to the weather and humidity. This wood features beautiful tones, characterized by lighter orange and pink tones.
Pink Peroba exhibits high density and remarkable durability. Despite being hard and hefty, it still shows a smooth texture that allows for different finishes. This wood has been frequently compared to the American oak and European beech. It is easy to work with and produces excellent results.
Peroba is becoming scarcer in the United States, and its price is in the mid to upper range. Its common usages include veneer, furniture, cabinetry, carvings, general construction, turned objects, crosses, garden sleepers, doors, banks, chairs, windows, and tables.
5) Cumaru
Cumaru often gets compared to Ipé because of their similar characteristics, but it is not as hard as the Ipe. Yet, it still carries a Janka hardness factor of around 3,300, which means it is seven times harder than that of redwood. It has a hard core that enables it to withstand termite and wood-borer attacks. It is also challenging to install as a decking material, but once installed, you can assure yourself that it will last for a very long time.
Cumaru is a managed wood, implying that you can buy it cheaper than other hardwood counterparts. You will find it used in many famous places like Coney Island’s boardwalk. The reason is it is exceptionally durable and rated for outdoor and indoor usage. It is also pest-resistant and rot-resistant.
However, it should be protected from UV light and requires coating during the first four to five years after installation. Besides, it is pretty tricky to cut and is not always available. Moreover, nailing requires pre-drilling.
It might also be susceptible to seasonal shrinkage compared to the abovementioned options. You can use Cumaru for wooden bridges, floors, pergolas, stairs, piles, posts, vessels, and decks.
6) Merbau
Merbau is an excellent and popular hardwood found in Southeast Asia, Pacific Islands, Papua New Guinea, and northern Queensland. It is often used externally in building, engineering, and maritime applications because of its sterling strength and durability. Moreover, it usually gets used for decking and flooring purposes.
Merbau has a Janka hardness rating of around 1,925, around 80% higher than black walnut and teak. It has elegant colors ranging from bright golden to dark brown with tiny golden sparks.
Merbau has an excellent density that makes it suitable for outdoor uses. Besides, it has remarkable dimensional stability that allows it to remain intact even in harsh conditions. It has a natural wood oil that contributes to its exceptional endurance. This oil protects it from worm bites and water.
However, it is 50% less expensive than Burmese teak and is resistant to termites. Thus, many people use Merbau wood for decks as an alternative to Burmese teak wood.
Merbau exhibits a sterling weatherproof property that makes it impervious to the vicissitudes of weather. You can use it in areas that often get exposed to water and high moisture. It often gets used for doors, windows, patio doors, siding, clapboard, bridge, planks, boat decks, terraces, swimming pool decks, and shipbuilding.
7) Larch
There are around ten to twelve Larch species. Larch wood is incredibly durable and weather resistant. It can withstand weather changes and is perfect for use outdoors. You can use it as a material for roof shingles and roof constructions. Larch often gets used in carpentry and construction for coatings and simple structures. It is also used for bridges and boats or in areas that exhibit higher humidity.
Larch is a softwood, but it exhibits natural resistance to rot. It is an attractive wood, primarily when used for flooring. Besides, it is an inexpensive option. You can also use it for building siding to protect the building from harsh elements.
Larch has pale creamy white to reddish brown tones. It also features clear dark stripes that are pretty obvious. Besides, its sapwood has a lighter tone compared to its heartwood.
However, there were reports that larch can cause skin irritation and allergies, and it exudes a distinct resinous odor when you work it. Moreover, it is more expensive compared to other softwoods.
8) Elm Wood
Elmwood is one of the most robust and durable water-resistant wood. It is known to last for many years, even if submerged in salt or freshwater. For this reason, it is often used for ship construction and in many other applications in port areas. It is also easy to work with and exhibits flexibility and versatility.
Since it is waterproof, it is perfect for areas with high humidity, like the bathroom and kitchen. It is also ideal for outdoor uses. Over time, however, elmwood increases its appeal and beauty.
Elm features a Janka hardness rating of 830 lbf. It exhibits a beautiful grain pattern. Moreover, its heartwood exhibits light to reddish brown, and its sapwood shows a bit of an off-white hue. Thus, elmwood often makes exquisite furniture.
Elmwood, however, is susceptible to insect infestation, but it is good to work. It also doesn’t exude any strong odor, but when it is wet, it exudes an unpleasant smell. Elmwood often gets used in boat building, planking, and hydraulic constructions.
9) Balau Wood
Balau is wildly distributed throughout the country of Malaysia, except in the swampy forests of that country. You will often find it in hilly areas. It exhibits water resistance and gets often utilized for floor covers and finishing materials. Besides, its grains are interlocking, which gives rise to a faint strip feature.
Balau’s texture, however, is even and fine. It is also most suited for heavy construction, wharves, bridges, railway sleepers, transmission posts, keels, beams, boat frameworks, bridges, and heavy-duty flooring.
Additional Wood Options and Tips
Aside from the abovementioned wood types, other wood types like Garapa, Fir, Pine, Sipo, Douglas, Sitka, Ash, and Spruce are still suitable for outdoor use. These wood types have excellent strength, hardness, and stability. Nevertheless, they need regular maintenance if you use them outdoors. If you fail to provide them with regular maintenance, they may fade and lose their colors over time.
Aside from these wood, there are also maintenance-free outdoor wood types like Sequoia, bamboo, Chestnuts, Afrormosia, Azobé , Arice, Olive, Acacia, Oak, Cypress, Massaranduba, Ipe, Teak, and Iroko. These wood types don’t necessitate treatments, and they could maintain their brightness and colors over time. They also exhibit remarkable resistance to harsh elements of nature like humidity, UV light, and other atmospheric agents.
How Can You Prevent Wood Rot?
The two main factors that lead to wood rot are moisture and exposure to sunlight. Other contributing factors likewise include fungi and insect attacks. If you can use rot-resistant wood, you will not worry much about wood rot over time, even if the wood is directly in contact with water or the ground.
Ground contact, for example, exposes the wood to fungi and mold that let moisture penetrate the wood. Once moisture gets into the wood fibers, it can split or expand the wood. You can employ a construction method that helps prevent contact of the wood with the ground and water.
Additionally, vines and plants that grow over or above the wood can speed up the rotting process of the wood.
To further ensure that wood rot will not affect your wood, you can use pressure-treated lumber or any of the wood mentioned above. You can also use paint or sealant on the wood’s outer surface.
Moreover, you should refrain from leaning any object on your siding and limit the direct exposure of the wood piece to the ground. You can also apply anti-fungal chemicals to the wood piece. Lastly, you should regularly maintain your wood if you want it to last for years or decades.
Conclusion
One of the metrics you should consider when choosing wood for your wood projects is its longevity. After all, you don’t want your effort, money, and time in building a wood project to go to naught if the wood you’re using are not meant to last longer. It is prudent, therefore, to consider how long the wood would last.
On average, however, wood lasts up to 15 years if it is like the wood mentioned above. Besides, if the wood is maintained regularly, it can last longer. However, mid-quality wood can get damaged within a few months in unsuitable conditions. Nevertheless, you can make wood last for a few hundred years if you provide it with artificial reinforcement.