Question : Aluminum Wiring – What Would You Say to Family, Clients.
I wrote this email answer to a nephew’s question about aluminum wiring systems. (He’s house hunting.)
Aluminum wire replaced copper in the 70s (for a while) because of cost.
Allowances were not made (at first) for the different properties so some problems showed up. (Fires).
– Connections have to be made with wire looped around the screws rather than just under the screws because of the coefficient of expansion for aluminum is greater than copper. They move and loosen with temperature changes.
– As aluminum oxidized it increases electrical resistance, the opposite of copper, so an anti-oxidant paste has to be used.
– Aluminum is more brittle and heats up more than copper, so for a given amperage the wire gauge or diameter has to be larger. (This is sometimes handled by lowering the amperage at breakers or fuses.)
– Outlet, switches and conductors for major appliances have different metals used for conductors (copper) so specially made adaptive plug outlets and switches must be used. (You don’t just find them in ‘Reno’ stores.) (NOW they are appearing, 2014)
Those are the major factors.
If the wire size is correct (or the amperage is reduced), the switches and plugs changed to the correct type, all attachments done as required for aluminum, and the anti-oxidant paste applied to all connections, then the system will be safe and as good as the copper based systems.
This does have to be verified by an electrician with experience in aluminum wiring. Unless they are over fifty or do a lot of renovations, there are many electricians out there who have never seen it. So ask.
*Sometimes sellers can provide a certificate or receipt from an electrical contractor verifying the system has been updated.
*If that’s the case then there is no real concern for the buyer, except that it will be an issue when they go to sell their house in the future.
*That is something to consider as it will be an increasingly rarer type of system in years to come.
That’s where my email ended. Those last few comments* address the future value and sales-ability of the home.
If you would give that advice to family, would you give it to all your clients?
Or would you leave it to the agents? As an inspector I would say Yes, as it is an element of the physical building.
What would you do?
Original blog post on ActiveRain: Link to Blog Post