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Copper tube and fittings are suitable for use in a diverse range of applications in building construction, which is testimony to their ability to provide long trouble-free service under a multitude of service conditions. Copper's reputation for excellence is based on decades of actual service experience in these applications. No accelerated tests which may or may not turn out to be accurate are involved. And the bottom-line is copper systems are cost-effective. When material cost, installation cost, and maintenance expenses over the life of a system are considered, copper becomes the solid choice for top performance at reasonable cost. Plumbing Underground Water Services: From the water main to the house or building, either Type K or L soft temper tube is used. They are available in long coils of various lengths in nominal sizes up to 2 in. With coils intermediate joints can be eliminated or minimized. Soft tube can also be bent around any obstructions or unevenness in the trench, and it adjusts readily to ground settlement. Compression fittings have become the most popular choice for underground copper water services in recent years, because of their high strength and ease of installation. Long coils of soft temper tube allow underground water services to be installed without intermediate joints. Hot and Cold Water Lines: Systems above ground inside houses and buildings are the biggest single application for copper tube and fittings. Copper installations extend from houses and vacation properties to office towers and multi-storey apartments, condominiums, and hotels. Hard temper Types L and M tube are commonly used, depending on service conditions; hard Type K may be needed in some cases. Canadian codes, except for British Columbia, allow Type M tube as the minimum requirement, and it is the most widely used. In B.C., Type L is required, because of water conditions. Special care should be taken with hot water recirculation systems, as covered on pages 14 and 15. Renovation and Remodeling: When remodeling, situations may be encountered in which soft temper tube, normally Type L, can be used to advantage, since its flexibility permits it to be worked inside partition walls with a minimum of difficulty. Drainage, Waste & Vent Systems: Type DWV tube with solder fittings is available in hard temper only. It is used above ground in multi-unit and high-rise buildings for drainage, waste and vent lines, and it should be considered particularly when noncombustible construction requirements must be met. Rainwater Leaders: Type DWV tube may also be used for rainwater leaders inside of buildings. Natural gas combo water heaters are ideal for multi-unit buildings, such as condominiums. Heating Natural Gas: The use of copper tube to convey natural gas has become the fastest growing new application for copper tube in recent years. The 2000 edition of the Canadian Standards Association B149 Installation Code permits the use of two Types of copper for above ground natural gas systems and propane systems - Type G/GAS tube meeting ASTM B837, and Type L tube meeting ASTM B88. For underground lines, Type K copper tube, plastic-coated Type G/GAS tube, or plastic-coated Type L tube, are required. Provincial regulatory authorities are expected to adopt these requirements. Local authorities should be consulted before specifying or installing any type of copper tube. Installation of a typical baseboard convector using 3/4-inch Type L tube. In Canada, Type G/GAS tube is also electrostatic spray painted yellow, or jacketted with yellow plastic, for easy identification. CCBDA Publication No. 14, available on request, provides detailed information on the design and installation of copper natural gas and propane systems. Propane: The use of copper tube and flare fittings for propane installations goes back for several decades. It is expected that the popularity of Type G/GAS tube for propane systems will also grow over the next few years. Part of the early Canadian experience with copper tube for natural gas systems involved existing propane systems which were converted to natural gas without retubing. The copper tube in the propane systems was adequately sized to meet the demands of the appliances, taking into consideration the lower calorific value of natural gas, and resizing was not necessary. These systems continue to give excellent performance. Fuel Oil: For small diameter fuel lines and connections between the oil storage tank and the burner, soft temper tube is usually used. General Purpose tube or Type L tube are typically selected. Hydronic Heating: In hydronic systems, hot water is recirculated in a closed loop to provide uniform heat in rooms. For large buildings, systems can be zoned to maintain various temperature levels in different areas. Hard temper Type M copper tube is used for circulation of the hot water from compact boilers to unobtrusive baseboard convectors. The tube inside the convectors usually has large fins to increase its heat transfer properties. Combo Systems: A relatively recent advance involves the use of combination units for heating water for the potable water supply and space heating. Gas-fired units are particularly popular for this purpose, but other fuels can be used. Since the heated water circulated through the convectors or heat exchangers is also potable, only materials permitted for potable water systems may be used. As a result copper tube and fittings are key components of combo systems. Radiant Heating: In recent years there has been a resurgence in the popularity of radiant heating. In these systems, low-temperature hot water is circulated through grids of copper tube embedded in a concrete floor or plaster ceiling. Soft temper Type L tube is commonly used for the sinuous or grid patterns in the floor or ceiling. Hydraulics, heat output, and location must be considered when selecting the tube size and spacing. Radiant panels which fit into suspended T-bar ceilings are also available. Copper tube has been used for decades for propane gas installations. Steam Heat: The high corrosion resistance and non-rusting characteristics of copper tube assure trouble-free service and reduce the maintenance of traps, valves, and other devices. Types K and L meet the requirements of the average steam heating system and Type M may be used for certain low pressure installations. Pressure tables will show which Type will assure adequate safety factor. On condensate and hot water return lines, it is recommended that the last two feet before the heating medium should be double the size of the rest of the line. For example, if the return line is 1-in. tube, then enlarge it to 2-in. Refrigeration & Air-Conditioning Copper is the preferred material for use with all refrigerants except ammonia. Huge quantities of copper tube and fittings are used in the fabrication of equipment and for the installation of systems. Type ACR tube (Air-Conditioning-Refrigeration) is covered by ASTM Standard B 280. It is degreased, dehydrated, and capped before it leaves the tube production plant. Nitrogen-charged or nitrogen-purged tube are also available. The nitrogen protects the tube and maintains a clean surface inside the tube prior to installation. Three copper medical gas lines in a hospital. Medical Gas Systems Medical gas systems convey nonflammable medical gases used for patient care in health care facilities, and include oxygen, nitrous oxide, medical air, nitrogen, carbon dioxide, helium, and vacuum lines. Hard temper copper tube is the only material permitted by installation codes for above ground medical gas systems in Canada. CSA Standard Z305.1 specifies that Types K and L tube manufactured to meet the requirements of ASTM Standard B 819 be used. B 819 tube is specially cleaned and is supplied to the installer capped or plugged. Care must be taken to prevent contamination of the system when the caps or plugs are removed. During installation and brazing, continuous purging with nitrogen is carried out to maintain a clean, oxide free interior. For copper-to-copper joints, a copper-phosphorus brazing filler metal (BCuP series) without flux is required. A flux is permitted when brazing dissimilar metals. Note: CSA Z305.1 must be referred to for details on the materials and joining methods permitted for medical gas installation. Residential copper fire sprinkler systems typically use Type M tube and fast-response sprinkler heads. Fire Sprinklers The National Building Code of Canada and provincial codes reference NFPA* Standards 13, 13D and 13R for the installation of fire sprinkler systems in buildings for all types of occupancies including residences. The NFPA Standards permit Types M, L, and K copper tube to be used for wet sprinkler systems, in sizes down to 3/4-in. A variety of joining methods may be used, including brazing, soldering, and epoxy adhesives. Tee-pulling tools and brazed joints are particularly suitable for installing the grids of tube needed to provide sprinkler coverage on floors of office buildings, for example. Mechanical couplings may be used for large sizes of tube. (* National Fire Protection Association) Snow Melting Systems A solution of hot water and glycol antifreeze can be circulated at temperatures between 50oC and 55oC (120 to 130oF) through copper tube embedded in concrete slabs or asphalt, to melt surface snow and ice from walks, ramps, driveways and loading platforms. Type L tube generally is used for this application, and it is buried about 1-1/4 to 1-1/2 inches below the surface, depending on whether concrete or asphalt is used. It is laid out in sinuous or grid patterns similar to radiant heating systems. Ground Source Heat Pumps Recent heat pump technology, known as direct-expansion, uses a refrigerant-filled copper coil which is buried in direct contact with the earth. This design eliminates the need for an extra pump and heat exchanger commonly seen in conventional ground-source heat pump systems which use a secondary antifreeze solution circulating through a plastic ground coil. The most efficient ground-source heat pumps use small sizes of ACR or Type L copper tube. The tube for the coil can either be buried vertically where space is a premium, or horizontally in medium depth trenches. Solar Heating Copper tube is used in the roof-top collectors in active solar energy systems, and for the lines joining the collectors to the circulation equipment. These systems capture energy from the sun to heat domestic water, which reduces a residence's energy consumption for regular water heating. A Gas-TecTM Copper Manifold provides ease of installation for copper gas supply lines.

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