Trunking in house (18th edition)

[peterhyper]

I admit to not taking too much notice of the 18th edition changes as I only took my 18th exam last week (no excuses I am not a good spark like most on here).

I have a flat to do that needs the lighting circuit rewired, but being the ceilings are like concrete and the owners don't want major disruption, it will be done in mini trunking. I usually use self adhesive trunking and seal it with white no nails to give it a strong fixing as drilling through concrete to fix screws in will be an absolute nightmare. So where do I technically stand not using metal fixings to secure it?

 

[Spoon]

So where do I technically stand not using metal fixings to secure it?

You have to use the proper fixing to stop the cable from collapsing, in case of a fire. This will involve drilling.

 

[Michael Sands]

You stand in front of the judge and try to explain why someone was strangled by your dangling live wires when trying to get out of a burning house

 

[telectrix]

what's the chance of fitting false ceilings on a 3 x 2 studding?

 

[buzzlightyear]

what's the chance of fitting false teeth and going out studding

I would def go with that .

 

[Andy78]

I've always fixed adhesive trunking anyway, the adhesive is for holding it to the wall while you fix it
D-line fixings inside the trunking too.

 

[freddo]

drilling through concrete to fix screws in will be an absolute nightmare.

Why is that? SDS drills are mighty powerful, then an impact driver to drive a concrete screw into the hole. Did a load of steel conduit last month into concrete walls and ceilings that way.

 

[Dustydazzler]

Unfortunetly you can no longer simply use sticky back trunking for re-wires. The plastic trunking and more importantly the cables in the trunking have to be fixed to the fabric of the building using a metal fixing.
There are many ways to achieve this from purpose made clips to a bit of cut up metal bandy strap.
Either way every single method will require fixing to the ceiling in this case.
Nomore nails glue will not meet the new regs

 

[billyblade]

Drilling through concrete using an SDS drill and good quality bits is not a nightmare.
Drilling through concrete with a combi drill and percussion drill bits is

 

[peterhyper]

Thanks guys.

 

[Squid]

How old is the flat and how is the current wiring run around the flat, did a job with my uncle many years back in a 1920's block and managed to utilise the old conduit and run in singe core cables.

 

[peterhyper]

How old is the flat and how is the current wiring run around the flat, did a job with my uncle many years back in a 1920's block and managed to utilise the old conduit and run in singe core cables.

Not sure how old the flat is, but I would guess 1940s. The current lighting circuit is in singles and is run inside steel conduit. I always try pulling singles through, but I haven't had much luck with similar set ups in the past.

 

[telectrix]

a bit of chip fat mixed with fairy liquid does wonders. cables will end up clean and greasy at the same time.

 

[peterhyper]

Forgive my naivety, but if I run mini trunking along the ceilings, are the metal fixings to support it supposed to completely cover the mini trunking. The reason I ask is because if the fixings are inside the trunking and a fire started, then the trunking covers would just collapse and the cables fall out?

I appreciate this new requirement is as a result of a very unfortunate incident causing the deaths of firemen, but in reality aren't there many other unsafe practices occurring everyday that are ignored (unless a part pee log is used).

Running 16mm mini trunking in a corner of a room is highly unlikely to trap someone in a building.

Also, if the mini trunking is fitted above the skirting boards, does that also have to adhere to the same criteria in case a person under 6" tall gets trapped under it?

 

[telectrix]

sticky back the trunking on, then use metal clips on the cable inside the trunking. several varieties to choose from, even more than heinz57.

 

[Charlie_]

Instead of ceiling lights have you considered wall lights or 5 amp sockets instead?

 

[peterhyper]

Instead of ceiling lights have you considered wall lights or 5 amp sockets instead?

Good question, but they want ceiling lights in the same place as the existing ones.

 

[Andy78]

Like this Peter ...

 

[telectrix]

at least with concrete ceilings he can fit 50kg chandeliers without reinforcement.

 

[Charlie_]

Or if you want to be really snazzy,
go for illunimated coving or
Led channel across the ceiling

 

[telectrix]

Or if you want to be really snazzy,
go for illunibated coving or
Led channel across the ceiling

now noww, youse gonna get a dumb for illunibated. .

 

[freddo]

The current lighting circuit is in singles and is run inside steel conduit.

If everything is going in the same place, I'd be using the existing conduit (unless it's really badly corroded).

 

[peterhyper]

So if I use 100mm wide plastic trunking on a ceiling, the actual cover doesn't have to be secured, so that could potentially catch fire and fall down and trap someone (weighing far more than 16mm mini trunkng).

 

[Squid]

at least with concrete ceilings he can fit 50kg chandeliers without reinforcement.

Just buy a table lamp, much easier........

 

[Squid]

Not sure how old the flat is, but I would guess 1940s. The current lighting circuit is in singles and is run inside steel conduit. I always try pulling singles through, but I haven't had much luck with similar set ups in the past.

Any cover plates on the ceilings for the junction boxes or the walls for the sockets?

 

[Charlie_]

now noww, youse gonna get a dumb for illunibated. .

Hahaha thanks for the tip off and not going straight in with the tag

 

[Spoon]

So if I use 100mm wide plastic trunking on a ceiling, the actual cover doesn't have to be secured, so that could potentially catch fire and fall down and trap someone (weighing far more than 16mm mini trunkng).

I think you are missing the point of the change mate.
Try being a firefighter for a day and then see how you feel.
The reg is changed to stop entanglement with cable. This can happen at any height. Feet, arms, heads & breathing equipment can all get entangled. When a house is full of smoke visibility can be virtually non-existent. They may have to feel their way through the house.

 

[peterhyper]

I think you are missing the point of the change mate.
Try being a firefighter for a day and then see how you feel.
The reg is changed to stop entanglement with cable. This can happen at any height. Feet, arms, heads & breathing equipment can all get entangled. When a house is full of smoke visibility can be virtually non-existent. They may have to feel their way through the house.

I clearly am missing the point. So trunking 6" from the ground above skirting boards has to follow this criteria in case it falls on anyone, and as per my previous post can 100mm plastic trunking covers be fitted unsupported?

 

[Spoon]

I clearly am missing the point. So trunking 6" from the ground above skirting boards has to follow this criteria in case it falls on anyone, and as per my previous post can 100mm plastic trunking covers be fitted unsupported?

If you use the word 'entangles' rather than 'fall' then it makes more sense.

Plastic trunking will melt in a fire. It will not entangle a firefighter like copper cable can.

 

[Charlie_]

I clearly am missing the point. So trunking 6" from the ground above skirting boards has to follow this criteria in case it falls on anyone, and as per my previous post can 100mm plastic trunking covers be fitted unsupported?

Metal trunking would be the best option in that scenario