All Hands On Deck

Bob Vila's Outdoor Deck Tips

(CBS)  Outdoor decks are one of the smartest home improvement projects one can undertake. A well-designed, well-built deck increases one's living space, makes entertaining guests a little easier and provides a wonderful place to gather or escape.

Cruise through any neighborhood, just about anywhere in the United States and one is likely to find more than just a few homes with outdoor decking. Some wood deck designs are as elaborate as the homes to which they are attached. Others are simple, straightforward additions that allow the homeowner to be amongst nature without truly being in it.

Whatever the intended use, outdoor wood decks can provide years, even decades, of use provided they are properly maintained. Wood decks, just like the exterior of a home or outdoor wood patio furniture, are exposed to high levels of stress from severe weather conditions that shrink and swell the wood. Total neglect or improper maintenance can result in a wood deck developing problems like cracks, raised grain, and mildew - all of which increase the risk of decay and insect attack.

A simple deck design is easy enough for the average home owner to construct, but more elaborate designs with fancy railings, multi-level designs, potting structures for plants or eating areas will require the assistance of a professional. After installing a new deck, it should be left untreated for about a month. This allows the wood to dry and better accept a finish. When staining, test the stain selection on a sample area. The deck should be completely clean prior to finishing. All finish should be applied to the deck when the surface is between 40 and 90 degrees.

Deck Materials:

In general, Vila suggests one consider a high-end deck material because they are dimensionally stable, resistant to shrinkage, and often inherently insect-repellant.

Traditional

Pine & Douglas Fir - ($9 - $16 per square foot installed)

Pine and Douglas Fir are the most traditional deck building materials. They are readily accessible across the country and are the least expensive way to build a deck. These types of decks will inevitably need replacing in 10-years, even with good care. Douglas Fir's strength, beauty and old-fashioned toughness are all prime reasons for choosing it for this type of project. It will maintain its appearance under extreme wear, and remain level without cracking, scuffing or splintering.

Pressure Treated Lumber -

Effective February 2002, the Environmental Protection Agency voluntarily decided to phase out a variety of pressure-treated woods that contains arsenic, in favor of new alternative wood preservatives. This transition affects all residential uses of wood treated with chromated cooper arsenate, also known as CCA (it contains inorganic arsenic), including wood used in play-structures, decks, picnic tables, landscaping timbers, residential fencing, patios and walkways/boardwalks.

The EPA is not asking for pre-existing pressure treated wood structures be removed. Although some studies have suggested that applying certain penetrating coatings (e.g. oil-based semi-transparent stains) on a regular basis (one re-application per year or every other year depending upon wear and weathering) may reduce amounts of the wood preservative chemicals from CCA-treated wood from leeching out. Total phase out is expected by January 2004.

The new generation of pressure treated woods are marketed under the names ACQ Preserve, NatureWood, and Wolmanized Natural Select. These products use copper-based preservatives.

High-End

The Cost for high-end decking materials will vary across the United States, so it's best to check first for the availability of the product, whether extra shipping costs are required, and what long-term maintenance costs will be involved. (Compare the figures to the cost of replacing a typical deck in ten years - one will likely find that quality decking is worth the investment).

Cedar, Cypress, Mahogany, Redwood - ( $17 - $23 per square foot installed)

These woods are long lasting, age naturally, weather naturally, resist excessive water damage.

Cedar

Cedar, a member of the cypress family, is richly colored with heartwood and it can last anywhere from 9 to 30 years. The top recommended grades of cedar decking are Architect Clear or Custom Clear deck grade. Western red cedar weathers rapidly to a beautiful deep glow. Port Orford cedar is a lighter in color than red cedar or redwood, allows more options for staining, and is rated for 20 years of wear. Pre drilling is not usually required for cedar, but is recommended near the ends to prevent splitting. Deck fasteners may react to the tannic acid in the wood, so stainless steel fasteners are your best bet. Cedar, like redwood, is also a good insulator, making it a good choice for decks located above living space.

Source: Georgia-Pacific.

Cypress

Cypress works easily and its grain takes stain, paint and preservative finishes. It has a low shrinkage factor. Cypress has good decay and insect resistance. It is suitable for both decking and porch flooring where appearance and durability are important. It is typically available in clear and knotty grades depending on your preference.

Source: Georgia-Pacific.

Mahogany

There are many different species and sub-species of mahogany. Colors can range from white and yellow to light and dark red. Meranti, a Philippine mahogany, comes in all colors and even has a dark red variety that looks like teak. Each Meranti color variety has its own faults and a wide range of decay resistance. It must be maintained with water repellant to protect it and keep its dimensional stability. Meranti is not as durable or dimensionally stable as real American mahogany, which comes from the West Indies, Mexico, and Central and South America. American mahogany has a beautiful, dark red appearance that will last for decades. Mahogany lasts up to 30-years. When buying mahogany, research the wood and be sure to ask for the species name of the wood you are buying.

Redwood

Redwood has a deep reddish brown color that deepens with age. It is fairly tight-grained and knot-free, lightweight yet strong. Redwood resists splintering and is less damaged by weathering than other woods with heartwood that can last over 30 years. In the South, where deck climates are harsher, sapwood lasts about 15 years while the heartwood lasts for over 20. Select Heart and Construction Heart are the optimal grades for redwood decking. The other four other grades, Select Structural, No. 1, No. 2, and No. 3, allow sapwood and should only be used if pressure-treated before installation. Like cedar, pre-drilling is not required but should be done near board ends to prevent splitting.

Source: Georgia-Pacific.

Dense (yet, still High-End)

Ipe ($22 - $24 per square foot installed)

Ipe is a South American wood that is also called ironwood, and by the trade name Pau Lope. Ipe is very durable and resists cupping, splintering and twisting. It is very strong and heavy, is low-maintenance, and will not shrink. It is extremely difficult to cut, however, so you can expect labor costs for installation to be very high. This wood frequently requires pre-drilling, but the denser the wood, the better it will stand up to foot traffic and weather. Ipe only requires sealant on the ends, but homeowners may choose to seal the wood and maintain its natural color or allow it to weather to a silver-gray while remaining smooth and splinter-free. Ipe should last over 25 years.

Source: New England Wholesale Hardwoods.

Composite ($18 to $20 per square foot installed)

Known by a number of brand names, most notably Trex and TimberTech, this durable blend of wood fibers and plastic weathers without disintegrating, maintains its shape, does not shrink or expand, and will last the lifetime of the residence. These plastic-wood composite products compare favorably with traditional pressure-treated wood decking and typically come paintable or stainable in brown and gray. Composite decking weathers, like wood, but will age to an even tone without deteriorating. It is dimensionally consistent, wont splinter, has no knotholes, is completely rot-resistant, and requires no annual sealing. Composite decking lacks the strength of wood, however, and wont span the same distances as wood. With appropriate structural support, composite decking is well suited to first floor and above ground decks. Plastic structural beams are not readily available in all markets and tend to make the deck bouncy, so pressure-treated wood is most commonly used to support this type of decking.

Source: Trex.

Maintenance:

For those with pre-existing decks there are two important focus areas when it comes to maintaining a deck: cleaning and finishing to protect the deck from the elements.

A deck can be discolored by: dirt and other foreign materials like tree sap, bird droppings, grease; fungal discolorations from mildew, mold, decay and sap stains; algae, moss and lichen growth; nail and other iron stains; tannins and other extractives from the wood; graying of the wood due to surface decomposition by sunlight and moisture.

To get a deck clean, homeowners can use any number of commercial cleaners now available. The cleaners fall into three different categories: chlorine bleaches, oxygen bleaches, or oxalic acid-based formulas.

To keep a deck looking good and to ensure that it lasts, the deck needs a good finish. Unless a finish is applied, discoloration and permanent damage can occur even with preservative-treated wood.
Vila recommends all wood deck surfaces be treated every two years with a synthetic sealant that is water repellant (these include penetrating finishes that are solvent-borne, oil-based water repellents, water repellent preservatives and oil-based semitransparent stains). These sealants contain UV-blockers, mildewcides, and algaecides to promote graceful aging of the wood.

For more from Bob Vila, go to his Web site.