Redwood is native to the coastline of northern California and southern Oregon and is a soft, lightweight wood that's fairly strong for its weight. Its distinctive pink or reddish hue becomes darker when finished.
This colorful wood is used indoors for veneers, paneling and some furniture pieces. The heart or inner portion of redwood resists rot and insects, making it a viable choice outdoors, such as for decking and patio furniture.
Deck Heart Redwood
Redwood lumber is graded according to color; the color also indicates which part of the tree the wood came from. Heartwood, closest to the center of the tree, has a deeper red color than sapwood, or the outer layers beneath the bark.
The inherent chemical makeup of heartwood resists insects and decay more than sapwood does, so many decking and other outdoor materials are made from heartwood. The deck heart grade of redwood is primarily used for decks, posts, fences and outdoor structures, and may contain a few knots and imperfections.
A slightly lower grade, called merchantable heart, has more knots, imperfections and possibly a few splits. This version is used for fences and retaining walls.
Clear Heart Quality
Clear-heart redwood is the highest grade available, free from knots and imperfections on at least one side of each board. Beside its decay-resistant properties, this grade of heartwood is all about the looks, lending it to use for cabinets, trim and molding, hot tubs, paneling and siding.
A slightly lower grade, called heart B, may contain a few knots and minor imperfections. This grade is also used for hot tubs, quality decking and garden shelters.
Burled redwood comes from knobby roots and areas of the redwood trunk. It looks a bit wavy or curly if cut and finished, making it a prime choice for decorative pieces such as lathe-turned vases, jewelry boxes, artwork, and household trinkets such as napkin rings.
Because of its look, especially when polished, redwood burls are prized more for their artistic value than purely construction-related use. Large burls may be used to make tabletops, with a high polish that makes the texture take on an added visual dimension.
Consider the Quality
If you're using redwood for your own projects, keep in mind the intended use and location of the finished piece. Heartwood is preferred for outdoor furniture and structures that need to withstand the elements.
High-quality grades of sapwood are well-suited to indoor projects, such as paneling. Heartwood is a must for structures on or near the ground, but given the relatively high price of quality redwood, many builders substitute with pressure-treated (non-redwood) lumber for ground-contact construction and for structural members that are concealed from view, such as the beams and joists of a deck.