Photo: Michal Bellan (Shutterstock)
Large outdoor woodworking projects, from fences to picnic tables, can present a challenge because the wood you choose will need to be able to withstand the elements. Choosing the right kind of lumber will help furniture and structures hold up better against moisture, temperature changes, and pests. Here are some guidelines to consider when choosing which type of wood to use so you can build outdoor projects that will last.
What to consider when choosing wood for outdoor projects
To choose best wood for your project, start by considering price, the intended use, the climate, and the tools available to you. Lumber comes in a variety of densities and has varying color, resistance to pests, and moisture levels. Decide on a budget, think about how much your lumber will get handled, consider the potential environmental challenges and whether or not you intend to apply a finish to it, and take stock of kind of tools and experience you have at your disposal.
When to use natural lumber
There are quite a few types of natural lumber that have qualities that make them well-suited for outdoor uses.
Red cedar
Red cedar is a common choice for outdoor use because it holds up well to moisture and is naturally pest resistant. This makes it a favorite for fencing, raised garden beds, and planters. Because it is a softer wood, it can scratch and dent easily, and it can also split when you’re driving in screws or nails. Cedar also contains tannins that can bleed into paint, so it will take some extra prep if you want to paint it to avoid stains. It can cost between $2.00 and $4.00 per board foot.
Cypress
Cypress is another wood that will hold up well to moisture, and it also is naturally resistant to warping, swelling, and pests. It can be used for trellises, furniture, or fencing. It has a light yellow to dark brown color and tends towards a straight grain with few knots. This wood will hold up well outdoors and is a softer wood, which makes it easy to work with but vulnerable to dents. It’s a good idea to pre-drill to avoid splits when driving screws into cypress wood. It can cost between $2.50 and $5.00 per board foot.
Black locust
Black locust is a hardwood that stands up to extreme temperatures, moisture, and pests. This wood is well-suited for furniture or other decorative applications. It is naturally resistant to warping and bowing and is nearly impossible to stain, scratch, or dent. Because it is so dense, it can be difficult to cut and will dull blades over time—and it can be challenging to stain for the same reason. It can cost between $5.00 and $8.50 per board foot.
When to use treated lumber
Pressure-treated lumber has come a long way since the days of arsenic-treated wood. The chemicals used now to treat pressure-treated lumber are much less toxic and safer to use, so it can be a good choice for decking or fencing. Usually, pressure-treated boards come from yellow pine, a soft wood, and won’t rot when exposed to moisture—and it’s not vulnerable to pests.
The downside of this lumber is that it can still warp or split from moisture, so it’s a good idea to seal or paint it. Wet pressure-treated lumber is heavy and is likely to warp, while the kiln-dried version is lighter and straighter but about twice the price.
When to use synthetic lumber
Composite wood is synthetic lumber made from PVC or other material. Because it’s synthetic, it can’t rot or be eaten by pests, and is very well-suited for use outdoors on decks, porches, and patios. It doesn’t need to be treated, but you can paint it if you want to. Working with composite lumber, you have to be careful of sawdust because it will persist in the environment—use a vacuum attachment and a drop-cloth when cutting composite wood.
