The main benefit of low maintenance decking is that you will never have to stain, seal or paint the decking like wood materials. Most higher quality synthetic decking materials are sold with a warranty against splitting, cracking, rotting and insect damage. Your local building department may require that the product you install has an evaluation service report from an accredited materials testing laboratory to provide proof that the decking will meet certain architectural standards. You can find a complete list of the ESR reports here. Another consideration is the installation instructions. Some low maintenance decking boards can be simply screwed down with special reverse thread screws to prevent the material from "mushrooming" on the surface. Other decking systems have a grooved edge to provide a surface to attach hidden fastener clips.
Most low maintenance decking products use polyethylene (HDPE or LDPE) plastic or PVC (polyvinyl chloride) as the base material for their decking boards. Composite decking is created by mixing polyethyle with wood fiber, rice hulls or other fillers as well as a blend of chemical additives. Most low maintenance decking planks are available in 5/4x6 dimensional boards in 12', 16' and 20' lengths. Some composite products are hollow and others are solid.
PVC or vinyl decking has become a popular alternative to composite decking in recent years. Some composite companies have created new products that encapsulate the composite material with a thin layer of PVC capstock for a hardened exterior shell that protects the material from stain, mildew, scratching and UV fading. As the material is extruded it is usually given a textured surface for slip resistance and appearance. Some products have reversible boards that have a wood grain side and a brushed finished side.
Most low maintenance decking materials can be machined and cut just like wood decking. Always read the installation instructions before framing your deck. Most composite decking is designed to be installed horizontally over 16" on center framing or diagonally over 12" on center joists. Most low maintenance materials are recommended to be installed at least 24" above the ground to allow ventilation below the deck. Most low maintenance decking companies also manufacture their own matching railing systems and accessories such as trim boards and low voltage lighting.
Remember there is no such thing as a truly no-maintenance material. Any outdoor living space will require occasional cleaning of dirt and debris.
As you can see here there is quite a bit of damage on the top of the joists. This could happen to wood frames after 15-20 years of use. Water doesn’t dry out between the floorboard and the joist as quickly as the deck surface. If you invest in a composite deck you should probably use joist tape to ensure the life of the deck frame. If you double your beams you should run 3” tape along the top surface to ensure water doesn’t get between the two 2x10’s. Your frame will last the life of your composite flooring. Average cost is $160 per deck. Click here for more information