Cables behind cladding: conduit?

[Dreadnaught]

I have question about cables behind cladding, in the ventilation gap. I will be installing the cladding after Easter.

 

It will be brick-slips cladding. The build up will be: 19mm battens, large cement-board backing-panels, and finally the brick slips themselves. Plus insect mesh top and bottom.

 

The question is: in that 19mm ventilation void, how can I later run cables (for lights, CCTV cameras, maybe a WiFi access point, and so on)?

 

I would run each cable vertically from the position down to the base of the cladding, then to underground ducts already buries that all lead back to my plant room. (I don't need to drill though the timber-frame wall.)

 

And I'd prefer not to pre-select the position for the items now so its the general principles I am after.

 

Should I perhaps run some oval conduit in the void in multiple locations just in case?

Or not bother with conduit and just feed the cable through the gap later?

 

What have others done?

 

Photo of some battens on my build ↓ 

[Dreadnaught]

Hi everyone, any thoughts on this? ↑ 🙂 

[Conor]

Easier to not run conduit and just feed cables through at a later date when needed. 

[Adrian Walker]

Since you already have underground ducts buries, I would run some cable in to the cavity.  Make sure you have a good sketches and photos of what you have installed. A tape measure in the photos will help later to find them.

[Mr Punter]

Have a chat to your sparky as they can be a bit sniffy about cables in external cavity walls.

[Russell griffiths]

Does the safe zone apply for this, in which case you should run directly vertical from the light fitting in case of future drilling cockups. 

 

[Dreadnaught]

Thanks for your comments, everyone!

 

I am still debating what to do. Whether to put conduits behind the cladding in advance. Or whether it will be easy to run cables later so that conduits aren't needed.

 

Any other comments, or real-life experiences with cables behind cladding, would be welcome.

[Nickfromwales]

30 minutes ago, Dreadnaught said:

Thanks for your comments, everyone!

 

I am still debating what to do. Whether to put conduits behind the cladding in advance. Or whether it will be easy to run cables later so that conduits aren't needed.

 

Any other comments, or real-life experiences with cables behind cladding, would be welcome.

I always drill through at a much later stage for the various projects I undertake, PH dwellings and airtight ones alike. It is of absolutely zero detriment to do so if done carefully, and sympathetically.

Conduits get fitted through correctly sized holes, executed and sealed according to the dwelling type, plus running slightly downhill to the outside to stave off ingress of moisture ( in the event of my thorough sealing-up ever failing ).

Getting from the ground up to the cavity would be an issue, with conduits needing to be surface mounted / exposed or set in place prior to the external 'skirting' arrangements being fitted. The location of your ducts would then command where the electrical device could go, eg where the cable could then rise in said safety zone.

 

Install all of these later, and spend the interim deciding what exactly to put where, exactly.  

 

 

[markharro]

On 11/04/2022 at 07:46, Nickfromwales said:

I always drill through at a much later stage for the various projects I undertake, PH dwellings and airtight ones alike.

Hi @Nickfromwales how do you manage this? We are building a PH and I am about to fix the battens for the cement board which will then be rendered. We need some penetrations from inside the house to outside for EV charger and ASHP flow and return and maybe some cameras. How to do these after the render is done?

[zzPaulzz]

Hi @markharro. What did you do in the end? 

[markharro]

Hi @zzPaulzz I drilled holes then threaded duct and then secured the duct with airtight tape at each end. For the rendered areas in some place I extended the duct through the cement board. In other places I drew the wires and took them to their final external locations prior to fixing the cement board. I'd recommend a lot of thought about the number of holes you need - I just about got it bang on...maybe one more might have been helpful

[zzPaulzz]

Sounds good. So you gave up on the idea of ducting behind the cladding? Did you cap the ends of your through-wall ducting with insulating foam after pulling the wires through? Just wondering about thermal bypass risk 

[markharro]

I never considered that. I have brought some ducts flush with the timber frame and other flush with the cement board/render. The flush one are where we will have timber cladding. I have not capped the ducts yet but will soon. Internally I am using Proclima gaskets and also externally in the main. Not yet sure about insulating - I certainly wont be using foam as I hate it so currently thinking I may stuff in some rockwool. I am thinking of using butyl tape to squeeze into external ends as a final airtightness measure.