Restoration Guide: Plumbing Design and Engineering

Editor's Note: This is article 11 of 16 in Chapter 8: The HVAC/Plumbing Guide of Old House Web's Home Restoration Guide. This guide was developed and edited for old homes from original materials in the U.S. Housing and Urban Development (HUD) Rehab guide.

11. PLUMBING DESIGN & ENGINEERING

Section 1--Overview

Indoor plumbing is a fairly new innovation in homes; many houses did not have it up through the early 1900s. However, if you have ever had to do without working plumbing for several days due to a storm or repair work, you know how dependent we have become on it. Depending on the age of your old house, plumbing may have been added during an earlier home restoration project, or it may have been installed when it was built.

This portion of the HVAC/Plumbing section is an introduction to plumbing systems, hopefully including the one you have in your old house. The plumbing articles offer considerations for updating your existing plumbing system, and also discuss other home systems that fall under the plumbing heading.

Section 2--Plumbing Design & Engineering Options for Your Old House Renovation

Plumbing systems in a home consist of the water supply lines, the waste and vent lines, and the plumbing fixtures. They can also include fuel supply and storage for heating and air-conditioning needs, fire protection systems, and any appliance venting and exhausting.

Plumbing design & engineering for new homes must meet strict code requirements prior to a house being occupied. Unfortunately that has not always been the case. As indoor plumbing became more popular, there were not a lot of guidelines concerning proper installation practices, and many plumbing designs were questionable at best. If you are remodeling an old house that has a plumbing system that appears to be fairly old, you may want to have a mechanical engineer take a look at the plumbing design & engineering of the house. Your initial remodeling budget might only allow making the system operable, and repairing any leaks or broken fixtures, but in the future there are several reasons why you might want to examine rehabbing the entire plumbing system.

2.1: Home Restoration Plumbing Safety Concerns

Plumbing engineering has advanced tremendously since the early days of indoor plumbing. Many early plumbing designs are considered unsafe today, or at the very least unhealthy to the occupants of the home. There are now devices on exterior faucets to help prevent contaminants from back flowing into the home's water supply. More is known about the placement of overflow drains to prevent contaminated water from entering back into the water supply system. Asbestos was used as an insulating material in many plumbing system installations, and lead piping was used in many old houses. Plumbing contractors now know about proper sizing and location of venting which helps prevent sewer gases from entering a home.

2.2 Home Restoration Energy Considerations

Energy conservation is another reason to add the plumbing system to your home renovation list. Water-saving toilets and plumbing fixtures are now available, and can save a considerable amount of water usage over a year's time. Engineers and plumbing contractors now have more knowledge of properly sizing supply lines in a home, and some homes even have pressure-reducing valves installed to reduce water pressure entering a home to more manageable levels.

2.3 Plumbing Code Considerations for Your Home Restoration

Many old houses have never had any type of building inspection. A home restoration is a good opportunity for a trained plumbing inspector to not only inspect the new plumbing in the home, but to also take a look at the existing plumbing system. The knowledge and training of a professional plumbing inspector can be helpful in making the decision as to whether your existing system is safe to use, or if rehabbing is in order.

2.4 Additional Systems for Your Old House

Another reason for examining the plumbing design & engineering of your old house concerns the advancements that have been made in additional home systems falling under the plumbing system heading. Until recently it was almost unheard of to have a fire protection system in a single family home, but they are becoming more common, and there is a possibility that they may become a requirement for new homes in certain parts of the country. A fire protection system can not only save your old house, it can also save lives.

There have also been advancements in the area of exhausting and venting appliances, which can make for a healthier and safer environment for your family.

All of these areas are covered in the following sections on plumbing systems. Existing systems that you may find during your home renovation are discussed, and options are presented for rehabbing and updating your plumbing system.