Alder is used in the building industry as an all-purpose cabinet material. It accepts stain readily to imitate other hardwoods, and due to similar grain patterns, is a viable stand-in for birch or cherry. Problems associated with alder are based mostly on its softness and lack of character.
Alder is among the softest of the hardwoods. On the Janka scale -- which rates the density of wood -- alder has a rating of 590. For the sake of comparison, pine has a Janka rating of 540, making alder just a bit harder. It can be scratched with a fingernail. Oak is typically the most widely used of all cabinet hardwoods, with a Janka rating of 1,290. Alder wood won't hold up to teenagers, children or abuse as well as most hardwood species. Dents are common on cabinet doors that are slammed too hard. Proper sealing and finishing can add durability to alder. If kids are grown and a certain amount of consideration is observed, alder will retain its beauty for many years.
Most alder cabinets have at least some alder plywood in their construction. The innate softness of alder relates to the durability of the plywood. Alder plywood is made with very thin sheets of veneer. This type of veneer is almost like paper. Extreme care must be taken to avoid sanding a hole in the veneer if you're building or repairing an alder cabinet; it's one of the most common problems experienced by the average woodworker. Another issue with alder plywood resides with the colors. Alder plywood is often made with several veneer sections. The result is plywood with darker or lighter strips on the same piece. The differences are sometimes like night and day, with contrasting colors on the same cabinet or door. Experienced finish workers can sometimes blend them, but it's almost always visible. Some of the color differences do not show up until they're stained, and then it's too late.
Alder lacks the broad, complex grain patterns of oak, ash or cherry. On the other end of the scale, it lacks the stately, straight patterns of white oak or mahogany. Alder responds to stain readily, but some consider alder bland and without character. The exception to the rule is knotty alder, which has a plethora of knots, swirls and color variations that impart a rustic appearance to cabinets. Knotty alder cabinets are appealing, but subsequent issues with exposed knots can be problematic.
Alder can change color in the sun. Also known as the "shadow effect," alder reacts to direct sunlight. Bleaching of hardwoods is not uncommon, but alder is brown to begin with. Even a moderate amount of sunlight can bleach the color to a lighter shade. If an object or even shadows remain on the surface of the alder when sunlight is present, it can produce a shadow that remains on the surface of the wood after the object is removed. The shadow effect is not uncommon in hardwoods, but woods including alder, teak and cherry are more prone to suffer from it than oak, ash or maple.
Woodworkers have determined that alder wood is the most stable when the moisture content of the wood is around 12 percent. It's typically kiln-dried, delivered and made into cabinets at this level. Even if you could check the moisture level in your own home, it's not always possible to maintain it. Air conditioners, heaters and outdoor conditions determine the humidity in most homes. Alder can crack, split or separate when too dry and expand when the humidity is too high. All hardwoods are subject to changing humidity levels, but the innate softness of alder make it more susceptible.
Screws, nails and other fasteners tend to strip out more easily in alder than in other hardwoods. The fiber-like grain doesn't have the holding power of more substantial grain patterns. Experienced cabinetmakers use course screws, or screws with fewer threads, when working with alder to address the problem. Nails may pull loose without proper length or purchase. Adhesive-coated nails are advisable when building cabinets with alder.