Millions of U.S. homes have either lead or galvanized water pipes. Studies have revealed that lead can be a health hazard. Galvanized pipe has drawbacks as well. Ask anyone who owns a home that is thirty-plus years old. Mineral build-up and corrosion in the pipes' interiors can result in a significant drop in water pressure and ultimately can be the cause of leaks.
Home builders began using copper pipes for residential water systems in the late '50s. This was not done for health reasons. That really wasn't an issue at that time because the potential hazards were largely unknown. Copper was used because it is far more rot resistant and easier to work with. This translates into significant savings in installation and customer service labor costs. In some cases copper was even used for drain and vent lines, many of which now are made of plastic.
Unfortunately, even copper systems have health drawbacks. Until the late '70s the solder used to weld the connections in water systems was half tin and half lead. Those systems can present a potential health risk as lead leaches into the water system. This problem is exacerbated with whole-house water softeners which tend to be corrosive, further breaking down the solder.
Today solder for water systems consists of 95 percent tin and only 5 percent lead. This makes copper one of the safest and most cost-effective choices for residential water systems. Plastic piping has overtaken copper in residential water systems in some parts of the country, although it accounts for only a fraction of the systems nationally. Moreover, its use is not yet permitted by many municipalities.
Weekend plumbers in the old days had to have an assortment of elaborate cutting and threading tools to assemble galvanized pipe. The pipe and the tools were heavy, cumbersome and difficult to work with. For today's do-it-yourselfers, copper is a blessing. It is light and doesn't require threading equipment. And with a bit a practice one can become reasonably proficient at sweating it. "Sweating" refers to a method of soldering that makes a strong joint in copper pipe.
As with any home improvement, the key to a successful job is having the right tools and materials. And working with copper doesn't require a tremendous investment in tools. All you'll need is a tube cutter and a propane torch. In addition to the pipe and fittings, you'll need emery paper, flux, a flux brush and a roll of solder.
Start by selecting the right pipe for the job. There are two basic types of copper pipe for domestic water systems. Type M and type L. Type M is for use above ground and type L can be buried in the ground. Type L has a thicker wall and thus is more expensive.
Use a measuring tape to determine the various lengths of pipe needed. When figuring the overall length of a piece of pipe make sure to take into account the ends which will slide into fittings.
Use a pencil to transfer the measurement to the pipe. Place the blade of the tube cutter over the mark on the pipe. Gently clamp down on the pipe by turning the grip clockwise while rotating the cutter around the entire circumference of the pipe. The cutter should move freely. Too much pressure too fast will bend the end of the pipe and damage the cutting blade. A bent end can result in a leak.
Use the deburring blade located at the end of the tube cutter or a small file to remove any burrs at the cut end. Polish the outside of the end to be soldered with emery paper until it has a bright finish. Do the same with the interior of the fitting to which it will be joined. This cleans the material and provides the necessary tooth for a solid connection.
Next, apply a thin layer of flux to the outside of the pipe and the interior of the joint. Flux is an acid that further cleans the pipe and causes the solder to flow more evenly. Assemble the pieces and rotate the pipe in the fitting to distribute the flux and ensure a secure fit.
Next comes the part where do-it-yourselfers make the most errors the soldering process. Soldering is not like welding where the flame is placed directly on the connection. When soldering, the tip of the blue flame should be directed at the fitting not the pipe. This allows the heat to radiate to the joint. When the flux begins to bubble, touch the end of the solder to one point of the joint and let capillary action do the work. The solder will automatically form a tiny bead around the joint. The flame should be removed once the solder begins to flow.
Be careful not to move or jiggle the pipe or fitting for about a minute after the flame has been removed to allow the solder adequate time to cool. After the soldering is complete, remove the excess flux by wiping off the pipe and fittings with a clean dry cloth. Discoloration or oxidation which may occur sometime down the road can be cleaned up with a tablespoon of baking soda in a cup or water.
Be sure to wear safety glasses and gloves. It's a good idea to wear long pants and long sleeves to avoid being burned by hot flying flux or solder. Gloves will protect hands from metal slivers and irritation caused by flux. Using a torch can be dangerous, especially if you're not experienced in its use. When working in tight places it's important to have plenty of ventilation. Avoid causing a fire when working near wood by using a metal shield between the flame and the combustible surface. Never use a torch around natural gas or gasoline and always have a working fire extinguisher nearby.
