Ask The Builder

When it comes to real-wood decks, redwood is the way to go

Friday, November 5, 2010; 9:17 AM

DEAR TIM: I'm about to build a new deck and love the look and feel of real wood. I've got my eye on redwood decking and wonder if it truly is all it's cracked up to be. Have you ever installed a deck using this material, and what can you tell me about it? Are there any special considerations or new products that will allow the wood to last longer? What type of maintenance is involved? -- Bobbie M., Durango, Colo.

DEAR BOBBIE: I've worked with redwood for years as a builder and a carpenter. I'd be lying if I didn't tell you I'm smitten with it. Not only is redwood gorgeous, it's naturally rot-resistant. Granted, it's not as durable as oak or maple when it comes to hardness, but it makes up for this in many other ways.

It's my feeling that a love of wood is hard-wired into our DNA. Our ancestors used it to build shelters, stay warm and dry, and cook their food. What I also love about wood, especially redwood, is that it's a crop not much different from wheat, corn or potatoes. The only difference is that the harvest time for redwood and other trees takes place after several years instead of months for most food crops. The bottom line is that we can grow redwood rapidly and continue to enjoy it for generations.

I used redwood on the last home I built for my family. It was used for all the siding and virtually all of the exterior trim. I didn't put in a deck like the one you want, but I've installed quite a few redwood decks that still look as good as the day I drove the last stainless steel nail.

I love redwood because it's easy to work with and it has natural chemicals in it that make it decay-resistant and not too tasty for most wood-destroying insects. It holds paint very well if you use it for a handrail. When you go to apply your redwood deck finish, you'll discover that it readily accepts penetrating stains that help preserve the natural grain and color of redwood.

Remember that water is the enemy of lumber, and when you decide to build with wood outdoors in just about any location, you have to protect the structure from moisture. Redwood can be damaged by water, but it resists that damage far longer than other woods do.

Water between decking boards should drain away as rapidly as possible. Redwood and other lumber woods were milled for many years in a way that produced boards with parallel faces. Although this seemed like a good idea at the time, it turns out that water could pool on these boards

You can now purchase redwood deck boards that have a unique profile. The top surface has a slight crown to it like a roadway. That means the center of the board is slightly higher than the edges, allowing water to readily flow off the board.

The edges of new redwood lumber are also canted inward slightly so that when two boards are placed next to one another, the gap at the bottom is wider than the top. This promotes excellent drainage and prevents organic debris from getting trapped between the separate pieces of lumber. Trapped organic debris holds water and accelerates wood rot.

Finally, the lumber mill cuts in two drip channels on the bottom of each board along the entire length. These grooves cause water that rolls under the wood to drip off the lumber instead of soaking the underside. All of these features help extend the life of the redwood.

When choosing a redwood deck cleaner, I urge you to use oxalic acid or try a mild liquid dish soap and water. Avoid oxygen bleach, as it can sometimes darken redwood. If your redwood darkens, you can often rejuvenate it by treating it with oxalic acid.

Tim Carter is a columnist for Tribune Media Services. He can be contacted through his Web site, www.askthebuilder.com.


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