Aluminum Siding
The first documented architectural application of aluminum was the mounting of the grounding cap on the Washington Monument in 1884. While extracting aluminum in limited quantity was possible as early as 1845 it was still a very pricey metal in 1884 much too expensive to be widely used.
Sheet-iron or steel clapboard siding units were patented in 1903. Some time in the mid 1920's Sears, Roebuck & Company started offering embossed steel siding in stone and brick patterns in their catalogues.
ALCOA began promoting the use of aluminum in architecture by the 1920s but it would be 1937 before modern siding was invented. An Indiana machinist Francis ("Frank") Hoess is credited with inventing in 1937 and securing a patent on the process in 1939 the method of using a locking joint, which was formed by small flap at the top of each panel that joined with a U-shaped flange on the lower edge of the previous panel thus forming a watertight horizontal seam. This design solved the problem of water leakage that all the then available metal siding designs seemed to have.
After he received the patent for his siding, Hoess produced a small housing development of about forty-four houses covered in his clapboard-style steel siding in Chicago. His operations were curtailed when war plans commandeered the industry and it would not be until after the end of World War II before aluminum became popular in residential construction.
After the war, in 1946 Hoess revived the business and achieved some success but was not as successful as rising stars like Reynolds Metals. His company remained in business until about 1960.
Vinyl Siding
Vinyl siding is plastic exterior siding material for a house, used for decoration and weatherproofing. It is an alternative to traditional wood siding or other materials such as aluminum or fiber cement siding. It is an engineered product, manufactured primarily from polyvinyl chloride, or PVC, resin, giving vinyl siding its name. In the UK and New Zealand a similar material is known as UPVC weatherboarding.
Vinyl siding was introduced in the late 1950s by an independent manufacturing plant located in Columbus, Ohio. The process was originally done through mono-extrusion. At that time, color blending was done manually, and the product was little more than a weak replacement for aluminum siding.
The original process made it difficult to produce and install a consistent, quality product. Beginning in the 1970s, a transformation of the product began, with the industry engineering formulation changes. These changes affected the product's production speed, impact resistance, durability, and range of colors.
Approximately 80 percent of its volume by weight is PVC resin, with the remaining 20 percent being composed of other ingredients that establish color, opacity, gloss, impact resistance, flexibility, and durability. It is the most commonly installed siding material for residential construction in the United States and Canada.
Vinyl siding can be rated based on thickness and durability. Generally speaking the thicker lasts longer. The thickness of the cheaper grade products may be as little as 35 mils. It can be as high 52 mils in the highest grade products.
The thinnest vinyl siding commonly used today is about 40 mils, and is known as "builder's grade". Almost every manufacturer has a product range from basic to premium grade products. So asking for the mil specifications is your first, best indication of quality.
Thicker vinyl products usually cost more, have a higher cost, are more rigid, look better when installed, and have predictable durability and life expectancy. Thicker grades of vinyl siding also have much more resistance to its tendency to crack in very cold weather when it is struck or bumped by a hard object.
Chemical formulas do vary from manufacturer to manufacturer and that can impact life expectancy. The most important is the UV coating that most major manufacturers apply to the surface of the product that filters out UV spectral light from the sun which would otherwise degrade the PVC more quickly. As a general rule, the higher the grade (and price) of the siding, the more resistant it is to fading.
