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Sorry to invade this post. Just a variance on the above... same situation apart from the plasterboard ceiling is up plastered and painted in a relatively new apartment. Customer wants light switch moved to opposite side of room as it’s currently in a silly place. 6m across room assuming it directly opposite. What do other people do to meet regs in this situation? Metal fixings and a load of large holes cut out the ceiling? It makes for a great fixing for the entanglement/ premature collapse issue but kinda messed up the fire integrity of the plasterboard ceiling. Any thoughts gratefully received also.
 
Quinetic switch
Thanks for the prompt reply. That was one thought. Customer wants original 3 gang switch removed and plastered over also dimmers in new position. So a cable run will be required. Historically people would have just pulled the cables through but with the premature collapse issue I just wondered what other people were doing in similar situations.
 
I agree they are. My problem/issue is the multiple number and size of the multiple holes. It’s a big hole needed to fit an sds drill/hand/hammer into the void to drill the reinforced concrete. Bearing in mind it’s a 6m run that’s a lot of holes in their new ceiling. ?
Large linian clip. The bigger SWA ones can fit several smaller twin and earth cables in one loop. Run them along in one go.
 
Used these many a time in the past but I don't know where you can get them these days. We knew them as Obos (obows, oboes?).
One fix, as can be seen, and an open/close clip....about 75x40mm. great for small bunches of cables above ceilings. I think they do some metal type's too.

1st flats with concrete ceilings IMG_2271 - EletriciansForums.net
 
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Big fan of Linian clips here. They have just introduced clips for fibre cables too.
Drill a hole, tap them in...job done. 1.5 and 2.5mm are so easy and fast to use, and the bigger sizes do SWA and conduit.
 
Is it a structural ceiling, what cover is on the reinforcement, do you have enough information to ensure you are not compromising the structural integrity of the floor above?

Do you know if the concrete ceiling is a pre-stressed member, or a post drawn area of a main structural element of the building, do you have the structural engineers drawings?

Any fixings in a regular pattern is like putting in a zip for a stress fracture to form, do you really think you are competent to make these structural decisions without taking into account the introduction of a path for moisture/condensation directly to the reinforcement.
 
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Is it a structural ceiling, what cover is on the reinforcement, do you have enough information to ensure you are not compromising the structural integrity of the floor above?

Do you know if the concrete ceiling is a pre-stressed member, or a post drawn area of a main structural element of the building, do you have the structural engineers drawings?

Any fixings in a regular pattern is like putting in a zip for a stress fracture to form, do you really think you are competent to make these structural decisions without taking into account the introduction of a path for moisture/condensation directly to the reinforcement.
would gorilla tape compromise the structural integrity, glue dissolving the concrete? ?
 
Is it a structural ceiling, what cover is on the reinforcement, do you have enough information to ensure you are not compromising the structural integrity of the floor above?

Do you know if the concrete ceiling is a pre-stressed member, or a post drawn area of a main structural element of the building, do you have the structural engineers drawings?

Any fixings in a regular pattern is like putting in a zip for a stress fracture to form, do you really think you are competent to make these structural decisions without taking into account the introduction of a path for moisture/condensation directly to the reinforcement.

Another good reason for still having a clerk of works, as used to be with local councils or building sites. Any contractors problems or worries could be sorted officially, by them. Now, in many cases......... on the contractor's head be it.
 
Used these many a time in the past but I don't know where you can get them these days. We knew them as Obos (obows, oboes?).
One fix, as can be seen, and an open/close clip....about 75x40mm. great for small bunches of cables above ceilings. I think they do some metal type's too.

View attachment 90136
Not seen these before. Thanks for the idea
Another good reason for still having a clerk of works, as used to be with local councils or building sites. Any contractors problems or worries could be sorted officially, by them. Now, in many cases......... on the contractor's head be it.
Indeed. These apartments were finished 5years ago so no clerk of works. I could get in touch with the builders easier enough for further info and I take on board Mike’s comments although his delivery could be refined...
His point highlights an issue for the electrical contractor which is why I originally asked question. One solution would to fix a cantenary wire from point a to point b but thus not needing a fixing in the reinforced concrete but the walls instead. The existing cables are already screwed into the existing reinforced concrete so “presumably” the concrete was spec’d originally for this.
I suppose the question is what do other people do in his situation. Just rod the cable through get the job done patched up and hope they don’t kill a fireman in the future Or, follow the regs and requirements for metal fixings and in the process destroy the existing fabric of the building and or cause the premature collapse in the case of Mikes comment and kill everyone living in the apartments?
 
And drill holes and notch timber joists wherever you like. ?
Some people like to work properly. There’s clear guidance on drilling holes and notching in timbers as I am sure you are well aware. You seem to only be interested in inflammatory rhetoric which isn’t what these forums are about although it seems like this particular forum seems to attract its fair share of spanners who’s only interest seems to jam up works rather than sharing their experience and knowledge to help find solutions. The world would be a much better place if ego took a backseat.
 
All round band is what is normally used, not sure I like it but it is very common.
I used to do similar

Chalk lines for the main data and power runs and fix your band at intervals and elsewhere where needed

Jobs I was working on were all hollowcore slabs with dropped mf grid ceilings

Never heard anything about structural risks drilling 5.5 mm holes ?
 
Thanks for the prompt reply. That was one thought. Customer wants original 3 gang switch removed and plastered over also dimmers in new position. So a cable run will be required. Historically people would have just pulled the cables through but with the premature collapse issue I just wondered what other people were doing in similar situations.
If it's any help, quinetic do dimmer switches.

Though on reading your post again, I see no reason not to pull the cables through the void (if there are no obstructions), as the ceiling will support the cables for at least 30 minutes in the event of a fire. Just like in a normal house with plasterboard ceilings.
 
If it's any help, quinetic do dimmer switches.

Though on reading your post again, I see no reason not to pull the cables through the void (if there are no obstructions), as the ceiling will support the cables for at least 30 minutes in the event of a fire. Just like in a normal house with plasterboard ceilings.
I didn’t know quinetic did dimmer switches I will look into that. Last time I checked them out they were just normal switches. Thanks for the update.

With regards to the dropping cable issues I thought the introduction of metal fixings was to prevent exiting homeowners and subsequently firemen from becoming entangled in cables. Apparently I was informed on my 18th that two firemen have died as a direct result of this.

I’m just wondering how any electrician is meant to provide such a fixing when in the above situation. In a house you can route cables through existing holes or notches in timbers. This apartment plasterboard ceiling is fitting into metal framing that’s then fixed to the reinforced concrete above. To adequately support the cable so it’s not dropping and putting strain anywhere would require multiple holes to be cut out so something like linian clips could be installed (subject to any structural engineers reports).

What should be a straight forward job of moving a light switch suddenly turns into a much more significant job to meet regs.

I have no doubt there are other people out there who would just pull the cable through and not worry about it. My work is usually house based so I haven’t experienced this situation before so I was wondering what other more experienced people do in this situation.

Maybe I’m just overthinking the situation. But the regs are the regs.

Many thanks for your ideas and responses though. I appreciate it.
 
I used to do similar

Chalk lines for the main data and power runs and fix your band at intervals and elsewhere where needed

Jobs I was working on were all hollowcore slabs with dropped mf grid ceilings

Never heard anything about structural risks drilling 5.5 mm holes ?
Thanks for your reply. I appreciate it.
 

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