It is not just the national power grid that is outdated. The wiring inside most of the houses is also antiquated, straining to supply our latest appliances, electronics, and lighting.
Allen Gallant, who is an electrician and has wired 6 houses of This Old House TV project says that the circuits in older homes were not designed to power many of the modern day gadgets.
There might be some obvious signs indicating strain – tangled power strips and extension cords sprouting from one outlet – or lurking unseen behind, ceilings, walls and the cover plates.
Protecting the Box
These days fuse boxes are less common than the circuit breaker panels. Fuse boxes work fine unless fuses with higher amperage than what can be safely handled by wires are installed. This can result in the overheating of wires and it can damage the protective insulation increasing the risk of fire. If the insulation gets damaged, danger remains even if the fuse of low amperage is replaced with the one having proper amperage. In order to fix this, old circuit has to be rewired.
Wiring problems can sometimes result in simple inconveniences and can even pose serious electrocution or fire hazards. In case you are buying an old house (especially one that was built more than 50 years ago), or if you have never had the wiring of your house inspected, hiring a licensed electrician to get your house thoroughly inspected is a great idea.
According to Gallant, the electrician will look at insulation on wires in order to see if the insulation is dried out and fraying. He will check for the corrosion in service panel and also look to see if anything unsafe was done by any of the previous owners. After that, Gallant recommends having follow-up inspection every 5 years.
You should not be alarmed in case the inspection shows code violations. Whenever, the electrical code gets revised, the old wiring is exempted, on the assumption that it was correctly installed. You are only required by the code to update the wiring in the rooms being renovated completely.
3 wiring problems solved:
In order to help you assess your electrical system, we have asked Gallant for identification of 3 most common problems related to wiring that he sees, dangers posed by these problems and the solutions he recommends for these problems.
Remember: Whenever you work with wiring, make sure that circuit at main breaker panel is turned off.
Following are three of the common problems you can face along with their solutions:
Overlamping is when a light fixture has bulb having higher wattage than what the fixture was designed for.
• Is overlamping a code violation? Yes, overlamping is a violation of the code.
• What is the danger level? The danger posed by overlamping is high. The intense heat of the bulb may scorch or even melt the socket and the insulation on fixture’s wires. This increases risk of arcing – the sparks which jump through air from wire to wire. Arcing is a major cause of the electrical fires. Damage to the wires and socket remains even after bulb is replaced.
• Solution of overlamping: The solution is to stay within wattage limit that is listed on all the light fixtures made in and after 1985. For the older fixtures that don’t have wattage limit mentioned, only bulbs of 60 watt or less wattage should be used.
2. Aluminum Wiring:
Aluminum wiring is when you have the type of wiring that was used in 1960s and 1970s as copper’s cheap substitute and is not considered safe anymore.
• Is Aluminum wiring a code violation? Aluminum wiring is not a code violation. You only have to change it if you completely renovate a room.
• What is the danger level? The danger posed by Aluminum wiring is high. This is because aluminum corrodes when it comes in contact with copper. It results in loosening of connection and it can result in arcing and fire.
• Solution of Aluminum wiring: The solution of aluminum wiring is retrofitting a dielectric wire nut that is approved for the aluminum wire (the price of a pair is less than $1) on to each aluminum/copper connection in the light fixtures. There is special grease in these nuts preventing corrosion while maintaining the conductivity. Ensure that any replacement switches are labeled AL-compatible.
3. Old Wiring: Is It Safe?
The standard wiring in today’s houses is insulated three-wire cable that is plastic-sheathed and is known as Romex, its universal trade name. But old copper wiring in older houses works equally well, if it is in good condition and has not been altered such that it violates code. Here are some of the most common wiring systems found in old homes:
• Knob and Tube:
This is the earliest wiring system in residences. It has hot-wire covered with cloth and neutral wire running parallel about one foot apart. Wire is anchored to house framing by ceramic knobs. Ceramic tubes are used wherever the wires penetrate framing or cross each other.
These can’t be grounded nor can they be spliced in to grounded circuit. If too much current flows through the soldered connections of this wire, they can melt. Disconnect the circuits covered with the building insulation; this causes overheating of this wiring.
• Armored Cable (Bx):
Knob and tube’s successor is armored cable (Bx). Neutral and hot wires are covered by flexible steel sheath. The wires are insulated with rubber covered by cloth. Ground is provided by the sheath and therefore grounded receptacles can be retrofitted easily.
The sheath should be securely anchored to metal outlet box. The condition of the wiring should be checked after every 5 years. This wiring degrades with time or if too much current flows through circuit.
• Two Wire Plastic Sheathed Cable:
This is an early PVC-insulated wire.
The plastic can get damaged easily. Grounded receptacles can’t be retrofitted to this cable