Chasing brick walls for plastic conduit

[neil7744]

Hello,

Not sure this is the right forum, but I'm wanting to know some info on channeling into a wall to run conduit...

Basically I want to put 2 25mm plastic conduit tubes in a wall so I can run cables from my lounge into the loft. I have already installed the back box. Is it ok to cut a channel 50mm wide x 25mm deep to run this plastic conduit? This won't affect the structure of the wall will it? I'd like to cut 1 single wide channel and run the 25mm conduit in parallel.

My Walls are double brick cavity filled with render and plaster on the internals. The reason I want to run 2 conduit tubes is I have lots of cables I want to get into the lounge for power, audio, video, satellite, networking...etc. I then want to plaster over the conduit and decorate the bedroom so everything is hidden.

Any advice would be appreciated.

Thanks

 

[Alarm]

Your dimensions are wrong.

You will need it wider and deeper.

 

[bernardgreen]

50mm wide x 25mm deep

As Alarm says this is too small for the conduit you want to run. You will need to pin the conduit to the wall be below the surface to enable a layer of strong bonding plaster between conduit and decor plaster.

This won't affect the structure of the wall will it?

Yes it will. Depending of on the quality of the wall it could seriously weaken the wall. A vertical channel will not serious affect its vertical load bearing capacity but if something hits the wall then the risk of wall cracking along the channel is significant. "something could be a child crashing into the wall or a sudden change of air pressure in the room due to strong gusty winds and an open door or window.

Run the conduits on the surface in or behind a wardrobe or ( as I am doing on a stone wall inmy cottage ) behind full length window curtains.

 

[Taylortwocities]

Guidance on max depth of chases HERE

 

[ban-all-sheds]

The reason I want to run 2 conduit tubes is I have lots of cables I want to get into the lounge for power, audio, video, satellite, networking...etc. I then want to plaster over the conduit and decorate the bedroom so everything is hidden.

Are you aware of the requirements for the segregation of Band I and Band II cables, and for the concealing of cables in walls?

 

[JohnD]

use oval which does not need to be so deep.

most or all of your chase should be in the plaster or render which does not affect the integrity of the wall. Oval is plaster depth.

 

[Chri5]

Are you aware of the requirements for the segregation of Band I and Band II cables, and for the concealing of cables in walls?

Which don't apply if there is physical seperation such as a barrier (conduit, trunking, trunking compartment) or if the cables were pinned and plastered over 50mm seperation would apply.

What's the depth between surface and brick on the wall ? (as in top coat and render. or just the plaster).

Depending on how you choose to fix the conduits you have a need for 25mm conduit + saddle 5mm + 5mm for plastering = minium depth

Here's a saddle

The width of the saddles needs to be considered, even stagger pattern and each conduit needing 4 saddles your need 60mm min width chase with 4 chucks out on each side of the main chasin to take the saddle "over hang".

If you have a stud / hollow wall might it be better trying to drop the cabling behind that?

 

[dhutch]

As said, as long as your within the thickness of the plaster your fine, if your cutting brick you ned to look into it more or change you plans.

I hate surface wiring.


Daniel

 

[ban-all-sheds]

Which don't apply if there is physical seperation such as a barrier (conduit, trunking, trunking compartment) or if the cables were pinned and plastered over 50mm seperation would apply.

Indeed.

So as long as the OP knows that (which was what I asked about), and given this:

I have lots of cables I want to get into the lounge for power, audio, video, satellite, networking...etc.

all the lots of cables except power will go in one conduit and just the power in the other then he'll be fine.

But if, OTOH, he was planning to divvie them up on the basis of what fits where......

Could someone with an electronic copy paste in 528.1?

• 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
  
  
• Current Wiring Regulations requirements for concealed cables.
  
  
  
  

 

[JohnD]

16mm T&E clips fit the oval conduit too.

when I use oval conduit I now tack it to the wall with no-more-nails or similar before plastering over (round here they use sand and cement render with hard finish plaster skim) and once it's plastered, it wont move again.

that way you have no clips or saddles needing to be buried.

Anything to avoid chasing the brickwork.

 

[Taylortwocities]

All he needs to do after that is try and find a way to thread the ready-made HDMI cables through that skinny conduit...

 

[JohnD]

sorry I haven't used HDMI. How big are they? Would they fit in the next size up of oval?

 

[Alarm]

someone is bound to shoot me down, capping?

 

[Alarm]

OOPS

 

[ban-all-sheds]

sorry I haven't used HDMI. How big are they? Would they fit in the next size up of oval?