Why are My House Lights Dimming?

Dimming lights a wiring a problem or power company problem, Let see!

All the power coming into your house arrives via a thick service entry cable, which is ended inside the main electrical service panel, usually located in the basement or, less often, in the garage. From there different branch circuits distribute the electricity to the various parts of the house.

The power sent to your home by your utility company fluctuates in voltage much of the time.
If the voltage drops and surges are within the specifications set by the power company, this is considered normal. Usually, this will not cause evidently dimming lights or other electrical problems (although it can depreciate sensitive electrical equipment like computers, TV’s, DVD players and other appliances over time).
But dimming lights throughout the house sounds as though it could be a problem inside the house itself and may not be related to the power company at all. The fact that your neighbors are not experiencing similar problems would seem to confirm this. If it were a power company problem everyone on the street would be observing dimming lights and malfunctioning appliances.
Most service entry cable installed these days is made of twisted strands of aluminum wire. The wire heats up under load and then cools down again, expanding and contracting during each cycle. The aluminum wire can also disintegrate, especially so if there is excessive moisture in the basement, or the cable end was not doused in anti-oxidant paste at installation.
Often, the type of problems you’re experiencing can be traced to a loose or corroded connection inside the service panel. If the dimming was only occurring in one part of the house, say the dining room, there might be a loose wire connection on the breaker or the fuse socket servicing just that one circuit. But since the dimming in your house seems to be happening all over, it could be that one of the screw lugs that secures the exposed ends of the service entry cable to the main breaker is loose.
In older homes dimming lights can also be a sign of water intrusion into the service panel or the meter outside. If the wad of flexible putty sealing the service entry cable and the top of the meter socket has worked loose, developed holes or cracks, or has crumbled away, water hitting the cable on the outside of the house can run down into the meter. From there it can enter the short section of service cable that runs between the meter and service panel. Once inside the service cable it runs easily into the service panel and causes corrosion inside. Badly damaged service panels often cannot be resuscitated and must be replaced.

If the home is newer, chances are there is simply a loose or lightly corroded connection. This is an easy and inexpensive repair for an electrician. An older home might have either of those conditions, or a water-damaged service panel – or some other problem we haven’t thought of yet.

But the bottom line is that you need to get his looked at by a professional. Opening up and trying to repair a service panel problem is not a do it yourself project. There is live electricity inside, and it can kill you if you don’t know exactly what you’re doing.