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Residential Construction

Why You Need to Specify Cast Iron Plumbing for Your Home
For most of us, the biggest investment we will make in our lifetime is the purchase of a new house or condominium. Whether constructing a new dwelling or altering an existing living space, new homeowners in the know are asking more and more questions about the materials in their new construction.

Today's homeowner is inquisitive about options such as windows, plumbing fixtures, and interior decorating themes. The value conscious homeowner is also looking beyond the frills and asking questions about the mechanical, plumbing and electrical systems too.

Homeowners realize that these hidden systems, which provide for today's living comfort, are not all the same. Insistence on different electrical outlets, heating equipment, and plumbing products is often the result of prior unsatisfactory experiences. This may be from reading articles or watching TV shows like 60 Minutes which focused on failures of plastic piping. Astute owners no longer accept any old "guts" in their new home simply because someone obtained a "deal" on the material.

We suggest that you focus attention on total value when selecting a drain waste and vent (DWV) system (the permanent and crucial system which conveys waste water from the house, across the property line, to the city sewers, and vents the plumbing system gases to the atmosphere.) By insisting on a cast iron DWV system you can assure yourself the same quiet, dependable DWV service that made cast iron soil pipe the industry standard for DWV systems.

Before 1970 most drain, waste, and vent (DWV) systems used cast iron pipe and fittings. Since then, many homes have been constructed using plastic (ABS or PVC) piping systems. Because the DWV systems are hidden behind the walls, most homeowners do not know the kind of pipe they have.

Many builders and homeowners have become aware of the noise problems associated with plastic piping systems. Due to these noise problems cast iron is now specified because of it's superior sound suppression. This time proven material is again today's choice for custom residences.

Why Cast Iron?
For centuries, cast iron pipe and fittings have been used to convey waste and water throughout the western world. Cast iron pipe installed at the Fountains of Versailles in 1623 is still functioning today. Cast iron plumbing installed in the White House in the 1800s still functions flawlessly. Reliable cast iron has proven its worth over the years in many demanding applications, an historical track record unmatched by substitute materials. For a more thorough history of cast iron soil pipe and fittings please follow this link to our history page.

The Quiet Pipe: Cast iron is known for it's quiet operation. Studies done by The Cast Iron Soil Pipe Institute (CISPI) have shown that cast iron soil pipe and fittings, because of their dense molecular structure and rubber gasket joints, are 750% more effective in reducing plumbing noise than substitute materials. The owner of today's $200,000 house will not tolerate the noise of waste water gushing down the living room walls through plastic piping materials when the quiet alternative, cast iron, is so readily available.

Easy to Install: Did you know that cast iron DWV piping often outlasts the building it serves? Today's cast iron systems use compression gaskets and couplings which are easy to install and easy to alter for future modification. With plastic pipe and fittings, using solvent cement connections, piping has to be cut out and thrown away if mistakes are made or alterations are necessary. Some people are unaware that hubless cast iron systems fit in modern stud walls more easily than plastic DWV systems, taking up slightly less space in the wall.

Strength, Durability and Safety: If you have ever visited a residential construction site where plastic pipe is being used during the stage when the walls are being "roughed in" you probably noticed that the contractor has installed small steel plates on the studs where the piping is installed. These plates are used to protect the plastic piping from being punctured when the drywall is nailed or screwed to the studs. Cast iron DWV systems do not necessitate the use of these plates since the nails or screws will not puncture the wall of a cast iron pipe or fitting. Consider the piece of mind you will have when you move into your new home and begin driving nails into the wall to hang pictures and shelves, knowing that you specified the use of cast iron pipe and fittings for your DWV system.

There is a very good reason the phrase "strong as iron" has worked its way into the english language, while "strong as plastic" fails to carry the same image of permanence and durability. None of the substitute DWV materials exhibit the strength of cast iron. Thin wall plastics such as ASTM D3034 lack the strength for under foundation installation. Buried cast iron is ten times stronger than some of today's thermoplastic materials which should be installed in accordance with ASTM D2321. In this specification for the installation of plastic piping materials the American Society of Testing Materials sets very rigid procedures and standards necessary to avoid failure of this non rigid piping material. Cast iron, a rigid piping material, has high crush strength and resistance to tree roots, penetration by rodents, and failures due to ground shifts. Unlike plastic piping, cast iron requires no costly bedding to support the walls of the pipe to prevent the piping from being crushed under the force exerted on the pipe in below ground installations. Also, the expansion and contraction of cast iron pipe caused by temperature (thermal) changes is far less than that of plastic piping and other materials. Failures from expansion and contraction due to extreme cold and heat are virtually impossible with cast iron pipe and fittings.

It seems strange to list "it won't kill you" as one of the benefits of a cast iron DWV system, but this benefit is one that sets it apart from many of the plastic materials used in construction today. Cast iron is permitted in all national plumbing codes and will, therefore, meet all local codes. From a safety and liability standpoint, cast iron is the safest plumbing material since it will not burn or produce toxic gases, unlike many plastic materials. For further information about plastic piping materials in building fires I recommend that you check out what Greenpeace has to say about the issue. Particularly interesting is the portion of this page which discusses building fires.

Environmentally Friendly: Finally, cast iron pipe and fittings are environmentally sensitive. Made from recycled scrap iron and steel, soil pipe and fittings represent a savings to our environment. Companies producing soil pipe and fittings are leaders in environmental control technology and have been energy conscious and ecologically aware for decades.

Cost Myths: There are several myths concerning cast iron soil pipe and fittings: The first involves cost and is a common objection raised by contractors or builders. They often cite to the homeowners that cast iron plumbing will drastically increase the price of the drainage system. It should come as no surprise to anyone that it is more expensive to cast a particular item in iron than it is to form it out of plastic. For this reason the cost of materials for a cast iron DWV system is frequently marginally higher than the same system utilizing some plastic materials. However, based on recent studies, the wholesaler cost differential between cast iron drainage and/or vent stacks and their plastic counterparts amounted to less than $150 per bathroom.

As a perspective homeowner, what you need to ask is "Can I give up my peace and quiet for this small price difference?" Perhaps a better perspective is obtained by dividing $150 by the total cost of your new home. The resulting percentage will be minor when compared to the overall project budget. Cast iron pipe and fittings provide a genuine value by ensuring the continuing quiet operation of your drainage system. For builders, the quiet system is a strong selling feature; for homeowners, it can be an important selling feature in an eventual resale.

Availability Myths: Other myths about cast iron are that it is not available and is difficult to install. Not true; the industry includes modern, well capitalized producers located strategically across the United States. There are almost no locations in America that are more than two days from foundry sites. In most areas plumbing wholesalers and representatives maintain a local stock of commonly used sizes and fitting configurations. This ready supply is a result of the fact that most commercial and industrial construction utilizes cast iron soil pipe and fittings, because of it's strength, durability, and long service life. Furthermore, most plumbers are very familiar with the installation of cast iron soil pipe and fittings. Ongoing plumber apprentice training continues to teach the installation of soil pipe and fittings as an essential part of their programs.

The Best Value: We are happy that you took the time to learn more about why you should insist on cast iron—The DWV material of choice—for your new home or remodeling project. Safe, time proven, quiet, and durable; your cast iron will let you rest assured that your plumbing performance will be flawless. You will be glad that you took the time to specify a product of long-lasting value to you and your family, the only DWV piping that is strong as iron—Cast Iron Soil Pipe.

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