Ask a Tradesman
Old wall sockets - take out metal back boxes or can plaster over them?
Hi I'm in the middle of a renovation and I'm adding all new double sockets. In regards to the old sockets, do you have to take out all the old metal back boxes or can you plaster over them? I've been told that if you don't take them out they will rust and show though the plaster at a later stage....I have never heard of this before??
What you've been told can occur, galvanised boxes eventually break down, rust and efluressence can surface after filling or plastering, primer can inhibit and slow down this breakdown. Also I've seen shrinkage because of irregular filling by leaving old cast conduit fittings, best removed and base filled with bonding or sand/cement base prior to patching or skim coat.
Answered 21st Oct 2013