September 16, 2013

Composite Building Materials

By: rbonnevie / Projects

The Good, The Bad, The Green

There are many good composite materials on the market ones that will genuinely perform as they advertise, however not all composites are the same. Manufacturers once claimed that composite decking would last a life time without fading, chipping, or warping and needed no maintenance. The story has changed over the years after many lawsuits against manufacturers and suppliers of composites have been won by consumers. Not all manufacturers producing composites stood up to the claims they made and as a result composite materials may have been given a bad rep, but there are also many plus sides to composite building materials.

 

Composite Building materials do last much longer then pressure treated wood and other building materials and do need less maintenance, that is not to say the product doesn’t need any TLC just not as much as wood. Composite materials can also be stronger than wood and resist fading significantly more. These composite materials can be used on many aspects of building such as decking, trim work, walls, roofs, siding and more. It comes down to finding a quality composite manufacturer.

 

Composite building materials are made from some wood and also many other various materials. From scrap plastics and other recycled materials to the pigments that give the product its color there are many ways the quality of these composite materials can be compromised. It isn’t easy to keep a consistency when you are using various elements. Creating composites could be compared to cooking, though a baker would not want to make a composite decking board. That’s because, unlike in a kitchen, you can’t count on the ingredients to be consistent from one day to another, due to the amount of recycled materials used. Pigments used to color the product make a difference, if an organic pigment is used then it can change more easily over time while non-reactive pigments are inert which means they “move” much more slowly thus not breaking down as fast as the organic pigments would thus keeping their color longer.

 

During the manufacturing process wood is shredded up and mixed with heated thermoplastic resin then extruded into desired shape usually by injecting the mixture into a mold. Some manufactures mix the materials together and form pellets with them, then the new material is re-melted and then formed into desired shape. One way to know you have a reliable manufacturer is to do a little investigation and find out the percentage of rejected product from the output line. The amount of rejected product should be about 8% if its below 10% the company may be intentionally allowing some less then optimal product to go through to company shelves.

 

BCI has found AZEK and Latitudes composite products to be some of the best material on the market today.

Sources:

ecobuildingpulse.com

greenbuildingsolutions.org

Wikipedia- how composite materials are made