Plaster over cable

[DIYWell]

I noticed some plaster had blown on a wall and started picking. Before I knew it I was down to floor level.

I spotted that the cable to the sockets had been clipped to the cinder block and plastered over. Is this the done thing nowadays or should I put some PVC channel over before replastering?

 

[ericmark]

It is permitted but not normal. Two reasons to use capping. Main one is to protect from plasters trowel and second some cable can leach plasticiser when in direct contact with some building materials but although I know it is possible never come across any where it has happened.

 

[ban-all-sheds]

It's fine, from a cable POV (I assume that the cable ran horizontally or vertically to/from the socket(s)?)

• http://www.voltimum.co.uk/files/gb/attachments/niu/l/attachments/c5-43.pdf
• http://web.archive.org/web/20061110111450/http://www.niceic.org.uk/downloads/concealedcables.pdf
• IEE article
• IEE Article on 17th Edition requirements for concealed cables.

However, if it's clipped to the wall, and the plaster isn't thick enough, maybe it was blown because you only ended up with a mm or so over the cables?

 

[ban-all-sheds]

It is permitted but not normal. Two reasons to use capping. Main one is to protect from plasters trowel

Plasterers frequently deny this, and given what they say, and what I know, about how much they care about the edges on their tools I'm inclined to believe them.

and second some cable can leach plasticiser when in direct contact with some building materials but although I know it is possible never come across any where it has happened.

I don't believe that's a problem with PVC cables and gypsum plaster. Rubber and/or lime might be a different story.

 

[1john]

the plaster has dried out too quick and that is why it hasn't bonded.

Electric off - water down some pva and then pva the inside of the chase (try not to get on the paint work as it is hard to paint over.

let the pva go off and apply another coat then plaster while still tacky. I would use one coat plaster to bulk it out, this can be ruled off flush with the wall. once it has set it can be sanded and have two or three coats of 'easy-fill' or jointing compound applied and rubbed back with some 180 grit paper to make a good finish.

 

[DIYWell]

the plaster has dried out too quick and that is why it hasn't bonded.

Electric off - water down some pva and then pva the inside of the chase (try not to get on the paint work as it is hard to paint over.

let the pva go off and apply another coat then plaster while still tacky. I would use one coat plaster to bulk it out, this can be ruled off flush with the wall. once it has set it can be sanded and have two or three coats of 'easy-fill' or jointing compound applied and rubbed back with some 180 grit paper to make a good finish.

Thanks for the tip