Cabling and Wiring

Pointers

Design

• Design for easy access and future removal. Install wiring in readily accessible wiring chases to simplify future modifications.
• Minimise wiring runs.
  • Design for future wiring needs, but avoid installing wires unless there is an immediate need for them.
  • Reduce material use by installing high-capacity runs to local hubs, rather than connecting each directly to a central hub. Local hubs can connect to workstations via wireless or short-wired connections.
• Install voice-data-video (VDV) cable that can serve upgraded networks so that cable will not become obsolete as quickly.
• Avoid wiring in exterior walls. This can interfere with insulation and may result in significant air leakage.
• Minimise electromagnetic fields. Rely on 'prudent avoidance' strategies to minimise exposure of building occupants to electromagnetic fields.
• Go wireless. Use wireless data connections instead of hard-wired ones for maximum flexibility and minimum material use. Wireless connections may be usable in some local areas, even if they are not usable building-wide.

Specifications

• Specify halogen-free products - look for polyolefin products; to use these for insulation and jacketing, compounds are typically added for flame resistance. Or specify polyolefin cable with lower flame resistance and place it in a fire-protected environment (eg, metal conduit or cellular cores of concrete floor panels).
• Wherever possible, specify wire and cable insulation and jacketing that do not contain PVC, chlorinated polyethylene, FEP, or products containing brominated flame retardants. Some PVC wire insulation and jacketing comprise 5 to 10 percent lead by weight. Specify products that don't contain lead stabilizers.
• Use fibre-optic cable. Fibre optics, widely used to carry voice and data signals, require less insulation and jacketing than copper wiring because they transmit light signals instead of electricity. It may be possible to run fibre-optic trunk lines to smaller copper distribution lines, thus reducing total insulated cable use.
• Avoid the need for plenum-rated and limited-combustion cable. Run data cable in metal conduit, sealed wiring chases, or cellular raceways in concrete decking to avoid the need for highly flame-resistant cable.
• Specify heavy-metal-free wire and cable. Cadmium, chromium, and other heavy metals are often using in pigments for wire insulation and jackets. Avoid them whenever possible.

Removal

• Remove old cable and recycle where possible.
• Follow safety precautions when removing old cable, which may contain high levels of lead dust.
• Reuse suitable components such as electrical boxes, flush boxes and fittings where possible.