How to Select an Appropriate Residential Deck Material

Over the last twenty years, my company has done about a thousand jobs in about eighty cities within about 2000 square miles in the K.C. metro area. Our biggest single product has been residential decks; and I am starting to get the hang of it. This article will bring you up to date on the main (old and new) types of deck flooring materials. Then we will go over some of their basic advantages and disadvantages. Armed with that information, you will be ready to select the right one for your situation. Remember however that the products are coming, going and changing all the time; so the approach to thinking about what to use is what is important.

Once upon a time, residential deck floors were made of boards nailed to a framework. About 85% of them still are. That percentage is slowly shrinking but will probably be a strong majority for a long time.

There are hundreds of different deck flooring materials made from wood, plastic, metal and wood-plastic composite blends. Wood tends to have lower initial cost but more maintenance effort and cost, especially if the desired color is not the natural weathered color. Wood looks like wood. Composites tend to be in the middle in initial cost, lower on maintenance effort and cost, and good for color retention. Composites do not look exactly like wood. Plastics tend to be the highest in initial cost, longest in expected service life and lowest in maintenance cost and effort. Plastics have a more finished look than composites but do not look like wood. The material that is right for you is the one that has the best overall package of features that are important to you.

Shapes of decking profiles (cross-sections)
To talk about decking today, we have to talk about profiles. Why are they important? They affect the way the floor looks; and some of the newer materials have different profiles. The “profile” is the cross section of the material. The predominant one is what most of us call a board or a plank. You have probably seen them around. They look like this.

Plank profile

Some planks allow spaces between the decking while others require spaces, especially at the ends. Some are designed to hide the fasteners (which are sometimes proprietary and required) so no nails and screws show; while others allow options on fasteners.

There are also channel shapes, planks with tongue & groove type (T&G) joints and planks with lap type joints. The way tongue & groove and lap type joints are designed to work and look varies with different manufacturers.

Channel, Tongue and Groove, Lap profiles

Additionally, profiles have variations and combinations of features like ribs and bull nose (rounded) corners.

Relieved and Bull Nose profiles

Most decking is wood and most wood decking is treated pine. Treated pine is treated to prevent rot (CCA has been phased out and has been replaced now with ACQ & other treatments) These are acronyms for the chemicals in the treatments. The wood most commonly treated is southern pine. The nature of the wood itself, not the treatment, makes it prone to twisting and warping.

Cedar is second in popularity in most places and has been used in the vast majority of our decks over the years. It resists rot and is considerably more stable than southern pine.

Other woods in use include:
Ipe (also sometimes called ironwood, Brazilian walnut—there are several species of ipe)—mostly plantation grown in a renewable way
Other tropical hardwoods, mostly plantation grown, such as pau lope

Composite decking is a distant second in popularity after wood.

“Composite” means that the decking is molded or extruded from a secret formula that is a mixture of wood and plastic. The wood is wood flour of various grinds and species. The plastic is most often polyethylene but is sometimes vinyl. There are different ratios of wood to plastic and different mixtures of recycled & virgin plastic. All of these things affect performance characteristics.

Examples of wood/polyethylene mixtures include products marketed under the brand names Elk, Epoch Evergrain, Geodeck (which has tongue & groove joints), Nexwood, Tendura (also T&G joints), Trex, TimberTech, Veranda, and at least 25 others.

An example of fiber/PVC mixtures is marketed under the brand name ProCell (and there are a few others.)

Composite profiles are mostly plank with manufacturers offering a few channel profiles and some with lap joints, e.g. TimberTech or tongue & groove joints, e.g. Geodeck.

Most composite decking is textured with wood grain or grooves but some is smooth.

Decking that is 100% plastic is pretty rare. Some is smooth and some is textured with grooves or wood grain.

Several manufacturers offer plastic decking under their brand names. Vinyl can come in a channel profile, e.g. Brock Deck, or in a standard plank profile, e.g. Veka, or planks with lap joints, e.g. Leisure Deck.

Polystyrene decking with a profile of a channel with ribs is marketed under the brand name Eon.

Polyethylene decking, marketed under the brand name ReNew, comes in standard planks or with tongue & groove joints.

Fiberglass planks (& other profiles) are also available.

Some plastic decking, such as Dura-Dri and Gorilla, has joints that are watertight to somewhat watertight to protect the area below from rain.

Metal decking for residential projects is extremely rare.

Aluminum decking is available in standard plank with spaces and also with tongue & groove joints with gaskets for a watertight floor. Arid Dek aluminum decking and alumiLAST decking use a lap joint system to make a waterproof floor. AlumiLAST also has an aluminum framing system.

Decorative steel grating systems are also available such as that marketed under the brand name Xccent. Xccent also has a steel framing system.

Advantages & disadvantages of material types
First, nothing is free and nothing is maintenance free. Washing with a hose is all that is needed for some. Many will require a pressure washer (which, if used improperly, can damage the flooring and create a need for remediation of pressure washing effects.) Some will require chemicals with or without some type of washing or flushing. Different kinds of stains, molds, mildews and weathering problems will require different kinds of maintenance methods and chemicals.
Second, nothing lasts forever. Generally cost goes up as service life goes up. However, maintenance for preservation and maintenance for cosmetics will vary with conditions and with personal preferences. Overall, deterioration tends to decrease as initial cost rises except that treated pine, the least expensive decking, is usually very durable with minimal maintenance; but it is seldom considered very appealing cosmetically.

Additional cost factors
Different decking materials affect other costs even though the decking itself is the single biggest material cost factor. Fasteners can make a noticeable cost difference in terms of the fasteners and the labor cost to install them. Compared to wood, most other decking materials will require more framing expense due to the nature of those materials.

Points to consider
• Wood looks like real wood and the initial cost can be low-but some is very pricey, e.g. mahogany
• Wood weathers and changes color-requires periodic staining to maintain a color other than the naturally weathered color
• Wood must be replaced (usually before other materials) at some point which varies with exposure, maintenance and luck
• Most wood takes some maintenance for best performance & service life
• Maintenance costs time and/or money and can offset initial cost savings
• Costs range similar to that of wood but somewhat higher
• Generally longer service life and lower maintenance cost and effort than wood
• Colorfast versions tend to maintain color over time much as does composition roofing
• Variety of textures, e.g. embossed wood grain, grooved, smooth
• Expands and contracts with moisture content of wood component and with the temperature of plastic component
• Tends to grow mold and mildew in the wood component-can be difficult and troublesome to clean completely
• Tends to stain-stains and cleaning methods vary with the type of stain and the type of the wood component
• Looks artificial, i.e. not like wood, to most people (and unacceptably so to many)
• Cost range tends to be higher than that of wood and composite decking
• Long service life
• Minimal maintenance effort and cost
• Maintains original look and color long term
• Variety of textures ,e.g. embossed wood grain, grooved, smooth, others
• Expansion & contraction with temperature-limits no-splice length
• Looks artificial, i.e. not like wood, to most people (and unacceptably so to many)
• Cost range tends to be highest
• Minimal maintenance effort and cost
• Maintains original look and color long term
• Tends to look commercial or institutional

Factors to consider in selecting the appropriate material
There are many factors to consider in selecting the appropriate material for your situation. The main ones are:
Initial cost
Maintenance effort & cost
Length of service life
Cosmetics-appearance of the floor (real wood, artificial wood, other texture, etc.)
Special features such as being waterproof to protect area below

To select the material appropriate for you, just start with the feature that you simply cannot live with or without. This will eliminate most of the possibilities. Then go to the next most important factor and keep going. This will probably lead you to a conflict or an impasse pretty quickly because you cannot have it all (all at once.) Then you will have to decide where to compromise and what is really important to you.

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Select An Appropriate Residential Deck Flooring MaterialCall us today at (913) 385-7374 or (816) 923-5865 or email us to arrange a consultation.