SUPPLY PIPING

Prior to the 1940s the majority of residential supply piping was galvanized steel. This is a very durable pipe that can last for generations. In the late 1930s, and especially post-World War II, copper supply piping became the industry standard. In the 1970s there was increased use of various types of plastic piping. However, copper piping has continued to be the material of choice for most traditional plumbing contractors to this day.

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Although galvanized pipe is very durable, it eventually begins to rust, and ultimately leak. The other downfall to galvanized pipe is the eventual build-up of sediment or corrosion inside the pipe. This results in a “hardening of the arteries” affect, eventually adversely affecting water flow and water pressure. For this reason replacement of galvanized piping with copper usually results in an increase in pressure.

Rusty and leaking galvanized pipe

Partially plugged old galvanized pipe

Copper pipe with soldered fittings does not rust or deteriorate in the same manner as galvanized pipe. Also, it is not prone to restricted flow from eventual build-up in the pipe. These qualities have made copper supply piping desirable for generations.

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Plastic supply piping has become popular greatly because the cost of copper pipe has increased. The most common type of plastic pipe in earlier years was CPVC (chlorinated poly vinyl chloride). The joints of this piping are glued together. It provides for a less costly alternative to copper, but it is less durable or reliable.

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The most modern type of “plastic” pipe is PEX (cross-linked polyethelyne). This is the color coded blue and red pipe that has prompted many of your inquiries as of late. The early returns on this type of piping have been very positive. Plumbing contractors in general have praised the cost benefits, ease of use and dependability of this pipe.

PEX supply piping with clamped fittings

PEX piping connected to copper

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PEX piping can be used in two ways.  Sections of the pipe can be joined or connected in a similar design to that of galvanized or copper pipes with elbows, “T”s, etc. The joints are rigidly clamped together (galvanized pipes have threaded fittings while copper pipes have soldered fittings).

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PEX piping can also be used in a “manifold” design. The manifold is located in the basement, near the main water service. This manifold feeds individual hot and cold pipes that seperately run from the manifold to each fixture in the house. This type of system greatly minimizes the number of joints or connections in the plumbing system. There is a single pipe feeding each fixture directly from the manifold to the individual fixture. Since plumbing problems often times occur at the joints or connections, a manifold system can theoretically reduce the number of problems that might be experienced as time passes. Also, the joints of PEX piping restrict flow and reduce the pressure. Manifold systems result in more uniform pressures to the various plumbing fixtures in the house. Although manifold systems are not the norm, we have inspected a number of modern homes with this type of system.

WASTE PIPES

Similar to supply piping, waste piping has also evolved over the years. Steel or cast pipes were used for decades in the early to mid-1900s. Much like its supply counterpart this type of piping was durable and reliable, but was also prone to eventual rusting and leaking. These pipes can become restricted or plugged.

Rusty galvanized wastepipe

Inside of old galvanized drain

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Cast iron waste piping was primarily used on the larger piping (3” and greater) and is less prone to corrosion, as compared to galvanized piping.  This waste piping is still used commercially; especially underground.

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Copper waste pipe was used in the late 1950s to the early 1960s.  This piping is very dependable, but it is cost prohibitive and somewhat labor-intensive when soldering large joints.

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In the early 1970s “plastic” or PVC drain pipe became the norm for residential use.  This remains the case to this day.  PVC drains are durable, reliable and do not tend to be prone to unusual restrictions or blockages.  Most PVC drain piping is glued at its fittings.  These connections are very dependable and are not prone to leakage.  Threaded couplers are also used on plastic or PVC drain pipes for traps and drain connections.  As a result, traps and drain extensions are very easy to clean and replace on an as needed basis.

PVC Drain connected to older cast drain cleanout at floor level

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We hope that you find this information to be beneficial, and that it helps answer some of the questions that you may have on this topic.  As is always the case, please do not hesitate to contact our office if we can be of any assistance.

By Douglas Burgasser

We have had numerous instances where clients and/or realtors have asked us whether a house that we are inspecting conforms with codes.  Home buyers sometimes confuse our inspections with code compliance inspections.

Pre-purchase engineering inspections of houses or buildings are not code compliance inspections. Such an inspection is considered to be well beyond the scope of a building inspection as defined by the professional standards that govern home inspections. By law, the local building department inspector (Code Enforcement Officer) has almost the final say in interpreting and applying codes.  Although we can sometimes comment on the applicable codes, the final determination must be the local CEO.

More importantly, it is critical to understand that existing homes will rarely conform to modern building codes and standards. This is because building codes are revised on a regular basis. As a result, today’s code would be different than the code that was in place when an existing home was constructed. The code at the time that the work (construction, repair, or improvement) was performed is the code that applies. There is also no requirement that existing homes conform to today’s codes and standards. Certainly, any renovation or repair work that is performed on an existing home must be performed in a manner that conforms to today’s standards.  We offer the three examples below:

Modern electrical codes dictate that electrical outlets in “potentially wet locations” be protected by ground fault interrupter protection. These locations would include some kitchen outlets, bath outlets, exterior outlets, pool equipment, etc. However, if a house was built in the 1950s it may not have ground fault protection for a bathroom outlet. There is no requirement that ground fault protection be installed. If this same bathroom were to be renovated the electrician who is performing the work would be obligated to install ground fault protection at the time of renovation. Today’s codes apply to the new work that is currently being performed.

Another example would be entry doors that separate a house from an attached garage. Modern codes for new work dictate that the door leading from the house to the garage must be a fire-rated door (usually metal) with a metal jamb. Also, a self-closing hinge is required for the door. This would prevent the door from being left open. The purpose of this code is to help prevent a fire from easily spreading from the garage to the interior of the house. If an existing house built in the 1940s has an attached garage, and the door leading to the garage is not a fire-rated door the homeowner is not be required to replace the door.  However, if they chose to replace the door, their obligation would be to utilize a door that conforms to current codes.

A third example would be that of automatic garage door openers. For a number of years new automatic garage door openers have been required to have redundant safety reverse features. This means that the door will reverse if it meets an obstruction or hits an object during the downward motion. Also, new openers must have an electronic eye safety reverse. This makes the door reverse if the electric eye (or safety beam) is crossed when the door is in the downward motion. Of course, there are many old openers still in use that would not conform to these standards. There is not a requirement that these openers be replaced.  The requirement would apply to openers that are currently manufactured and installed.

Homeowners should also understand that overzealous contractors will tend to overstate the necessity for proposed repairs or modifications based on code requirements. Once again, homeowners should understand that in many cases work does not need to be performed strictly because an existing component does not conform to modern codes. However, it is also important to understand that codes have mostly been established in the interest of safety. As a result, homeowners should consider modifications as an improvement and for the benefit of increased safety in their home and to the occupants.

On a related topic we have also seen an increased concern for finished basement space. Fire and safety codes that have been in place for decades dictate that basement space cannot be considered living space without a second means of egress. Since the mid 1980’s, finished rooms in a basement are only permitted if there are two exit points. The stairs leading into the basement would be one exit point. The second egress is usually an appropriately sized window or a door. There are also definite requirements that dictate whether a window would be an acceptable means of emergency egress. The window must be a certain minimum size (width, depth and square footage of opening), and the bottom of the window cannot be more than 44 inches from the basement floor.

A basement level bedroom must be equipped with its own means of egress. In other words, if a house has a finished basement that includes two bedrooms there must be an egress window or door from each of the bedrooms.

We hope that this brief explanation provides some clarity to the questions surrounding code issues and finished basement spaces.  Please do not hesitate to contact our office or any of our engineers if you have any questions in this regard.

By Thomas Wurzer, P.E.