JPCoetzee:
Some of them have roughly-tacked together wooden back boxes and these should be metal (!).
No!
If you put in metal back boxes, you potentially have exposed conductive parts because of the screws unless the switches are of a type which conceal them.
The wooden back boxes may be as rough as a badger's ars*, but so long as they are reasonably sound, they are unlikely to present a danger. If some of them are roughly tacked together, are others beautifully joined, or what? ?
JPCoetzee:
Some of them have roughly-tacked together wooden back boxes and these should be metal (!).
No!
If you put in metal back boxes, you potentially have exposed conductive parts because of the screws unless the switches are of a type which conceal them.
The wooden back boxes may be as rough as a badger's ars*, but so long as they are reasonably sound, they are unlikely to present a danger. If some of them are roughly tacked together, are others beautifully joined, or what? ?
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