You can’t beat the durability and the low maintenance advantages of synthetic, faux wood materials. But I’ve seen lots of synthetic, wood-look materials, and although a few of them look pretty realistic, some people feel that no synthetic material can match the natural beauty of real wood. And for those people, that beauty is worth the extra maintenance required to use authentic wood for the exterior of their homes.
For those of us considering using real wood on our new homes, whether as decking, or as exterior wall cladding, fences or garage doors, we’ll take a closer look at some of the most popular wood species used for exterior applications to help us decide which wood might be best for our projects. We’ll also briefly consider composite and plastic wood alternatives.
Although no wood is completely immune from rotting and insect damage, some species resist decay better than others. The three most widely available naturally insect- and rot-resistant species include Western red cedar, redwood, and cypress. These woods are suitable for exterior use without having to be treated with chemical preservatives, although stains and sealants will protect these varieties to an even greater extent.
For many varieties of wood, the level of weather- and bug-resistance is directly related to the amount of heartwood in the boards. Heartwood comes from the center of the tree, and is relatively hard and very resistant to decay. Sapwood comes from the outer part of the tree, near the bark, and is softer and more susceptible to decay. As you might imagine, heartwood is more expensive than sapwood.
Your geographic location will determine the availability and cost of the different types of wood. Redwood, for example, is widely available and used in the western United States. Western red cedar is commonly sold in the Midwest, and cypress grows throughout the Southern and Southeastern US.
Let’s talk about those species and a few more in greater detail.
Cypress grows in swamps. Its sapwood is almost white, while the heartwood color varies from a light yellow to dark brown. Although its strong and dense, cypress is not so dense that it’s difficult to work with. It is easy to cut into boards.
Another advantage of cypress is that it performs well in humid locations. Although cypress can work in any climate, it’s an especially smart choice in humid or coastal areas. Humidity can cause warping in many other types of wood, but cypress is an exception. Because it grows in swampy, humid areas, it can withstand the elements well. If you need exterior wood on a home close to the beach or in the deep south, you might strongly consider cypress.
Despite it’s many advantages, Cypress has one major drawback. It can be expensive. The appeal and relative scarcity of cypress means it’s increasingly harder to come by, and its price reflects that.
Redwood is a good choice for all climates. It resists shrinking, warping or cupping. It absorbs and retains its finishes very well and requires less maintenance than some other species. Redwood is also naturally insect resistant, not only on the surface, but also throughout the wood. Its regionally available in the West, and can be difficult and more expensive to obtain in other regions. Because it’s so dense, redwood can split when nails or screws are driven into it. And redwood’s tannins can bleed to its surface causing unwanted discoloration. Tannins are internal extracts or oils found within wood that extend to the surface of the wood causing splotchy stains. Fortunately, you can avoid the bleeding of tannins by properly sealing the wood.
Cedar is best known for its beautiful straight to slightly curved grain and its resistance to insects and rot. It takes a stain well. Cedar is dimensionally stable and resists swelling, shrinking, cupping and splitting. Although cedar is naturally more moisture- and insect-resistant than many other woods, but it must also be sealed and stained, or painted to retain those properties. Cedar can easily finished with oils, paints and stains. Like redwood, cedar has tannins which can bleed to the surface of the wood, causing discoloration.
There are a number of varieties of cedar growing across the United States. Different cedar varieties range from from red to yellow to white.
Western red cedar is obviously more red in color than other cedars. Red cedar is also very long lasting, warps less than other varieties, and is less expensive than other cedars.
Yellow cedar is a much heavier wood than red cedar because of its natural wood oils and its tight grain.
White cedar grows predominantly in the eastern United States. It is considered one of the finer grades of cedar and has a light, blonde color and has distinctive, pleasant scent.
White oak is also known as the "whiskey barrel" wood. It is much less porous than red oak so moisture can’t readily wick into its end grain. White oak is not as commonly used as other wood species for exterior applications, but white oak is has an appealing straight grain, is super strong and its heartwood resists decay. Like redwood and cedar, white oak splits rather easily, so you do need to predrill screw holes.
Ipe is the new kid on the block. It’s imported from Central and South America, where it grows rapidly. Ipe is also called Brazilian walnut. It’s also been named "ironwood" because it’s so strong. Because ipe is so strong, screw holes must be predrilled and you might burn out drill bits in the process. Ipe is medium to dark brown in color, and it has a reddish tint. It’s a very dense, stable wood that can last as long as 25-40 years even if left untreated. It resists movement, warping, cracking, decomposition, and denting. Because of its density, ipe doesn’t accept stains and sealants very well, so you’ll do best to let it gray and age naturally or try a penetrating oil or sealant. Ipe is relatively expensive and sometimes hard to find, but ipe costs about the same as many composite wood products.
Teak is not only one the hardest of all the wood species, but can also be hard to find. It’s still available in small quantities, but you'll pay a pretty penny for this exotic favorite. Some varieties of teak are considered endangered species. Although some species of teak are grown in the United States, most come from Asia. Teak has a beautiful brown color and straight grain. It’s dimensionally stable and naturally water and insect resistant. Although teak is considered a fairly low maintenance wood, it does need to be oiled every few years to keep its luster, color and insect and water resistance.
Now let’s move on to the soft wood species, including pine, spruce and fir. These soft woods are not naturally insect and moisture resistant as many hardwoods are, but they can be used for exterior applications if properly treated. Soft woods need to be chemically treated and regularly maintained and sealed in order to resist moisture, insects and decay. This involves impregnating the wood with chemicals such as boron, which helps stop decay and increases its resistance to fire.
Pine has long been a standard for exterior home projects. Pine is affordable and it’s available from coast-to-coast. Because it is a soft wood, it’s less expensive than harder species. And It’s easy to cut and fasten with nails or screws. Pine holds a finish well and is a good material to use for surfaces that you want to paint or stain. Most pine for exterior applications is milled from southern yellow pine. That southern yellow pine is then chemically treated to resist rot, fungus and insects.
One challenge with pine is that it may be difficult to purchase knot-free pine in longer lengths. Another downside of pine is that it's not very dimensionally stable, so it has a tendency to crack, split and warp. You need to be careful not to purchase fast-growth pine for because it can be especially prone to cupping and splitting. Routine maintenance is necessary to prolong the look and lifespan of pine. Maintenance includes power washing and staining or sealing every 2-3 years.
Spruce is a soft wood that is a member of the pine family. It is readily available on the East Coast. It can be used as a substitute for pine and has a similar price. Spruce has many of the same characteristics as pine, but spruce comes in longer lengths.
Like pine and spruce, fir is a soft wood and another budget friendly option. It comes in long lengths, is easy to cut and install, and takes a finish well. It is most readily available in the Western US.
Wood/plastic composites (WPCs) are made from plastic resins plus wood flour and wood fibers. Some also use recycled material. Surprisingly, some solid composites are not as stable as you might think and can expand and contract, especially along their lengths. They heat up in sunlight and they lack rigidity. However, they don't splinter and can offer good traction in wet conditions.
Premium composite products have color going all the way through the boards instead of just a coating, so scratches won’t be as noticeable and the boards will not stain or fade, and they have excellent mold resistance. (cheaper composites have had some trouble with mold).
Plastic wood, also called PVC , looks like wood (or kind of like wood) but is made of 100% plastic with no wood fibers. Like composites, plastic wood can expand and contract in certain climates. This can cause loosening of joints and make decks and siding unstable. In hot, sunny areas, plastic decks can get very hot on the soles of the feet. But, plastic wood, like composites, is very low maintenance.
Here are some final things to think about when considering real wood for your project…
Local wood is usually 40-50% cheaper than species that need to be ordered from other parts of the US or from outside the states. When selecting a species, it's very important to get the one that best fits the climate you live in, as different types of wood have different weather resistance properties. Ask local contractors and lumber yards which woods work best in your climate. Remember, swampy cypress works well in humid, coastal areas.
Compared to other exterior materials, wood can be replaced and repaired easily. DIY homeowners can do the simple repairs themselves. The cost of labor to repair wood is not as expensive as the cost of repairing some other types of materials, such as aluminum.
One of the main reservations that homeowners have about installing exterior real wood is that wood needs more maintenance of almost any other exterior material. Maintenance includes restaining, repainting and/or resealing about every 3-5 years, depending on your climate.
Be warned, even with the best maintenance, almost all wood will turn gray and eventually deteriorate. Maintaining wood with stains, sealants and paints will slow the rate of its deterioration, but, over time, all wood will need to be replaced. Generally, you can expect most species of well-maintained wood to last of about 30-40 years.
To prevent mold and fungus growth, mold repellents must also be applied. And termite repellants should be applied to wood species that are not naturally insect resistant. In some areas, woodpeckers can also cause damage to real wood. But moving, shiny objects will usually scare woodpecker into not bothering your house. Things like metallic pinwheels or
shiny mylar tape that hung so it will move in the wind.
If left alone, without regular maintenance, wood is prone to excellarated graying, drying, cracking, warping, splitting and rotting.
Because exterior wood is available in many different types and grades of species, pricing varies greatly. More durable species, such as redwood and cedar can cost 2-3 times more than the more economical varieties, such as pine. A good rule of thumb is to buy the best grade of wood you can afford.
On average, you should expect to pay $5-10/sq.ft installed for non-exotic wood species. Exotic species like ipe and teak will cost more. When deciding whether the beauty of real wood is worth the cost, don’t forget to factor in the cost periodic maintenance that wood will require.
The bottom line is, if you choose real wood for the exterior of your new home, choose it for aesthetic reasons, not financial or practical considerations.
1. Which of the following is not a softwood?
The answer is A. Teak is not a soft wood. It is an exotic hardwood that is naturally insect and moisture resistant. Softwoods need to be chemically treated in order to be insect and moisture resistant.
2. True or False. Synthetic composites are dimensionally stable and don’t often contract or expand.
That is surprisingly false.
Please remember that the purpose of this podcast is simply to educate and inform. It is not a substitute for professional advice. The information that you hear is based the only on the opinions, research and experiences of my guests and myself. That information might be incomplete and it’s subject to change, so it may not apply to your project. In addition, building codes and requirements vary from region to region, so always consult a professional about specific recommendations for your home.