SWA needs to go from the exterior to the interior - put a junction box or not?

[swaRRR]

I'm running SWA up the outside of a house and am wondering how best to make it off.

It's going to come from the loft area, to the outside, down the house and then into a brick lean-to where it will be made off on some trunking after 500mm of run inside the lean-to.

Since the armouring needs to run on the inside of the house and lean-to for several meters, i'm not really seeing the point of making it off into a junction box and then connecting more SWA to run from that to the inside of the buildings; just seems like it's introducing unnecessary potential failure points in what could easily be an entire intact run.

Obviously the wiska/JB looks much better but what do you guys think? Is running SWA straight into a hole in a building rough? If you're using a JB how are your doing it; making it off with a gland, using an IP65 stuffer?

 

[Dustydazzler]

If possible I would keep the SWA continueous and do-away with adding a joint box, nowt wrong with drill a hole and running the cable inside to out , just gun a wee bit of silicone gel to seal the hole up nicely

 

[swaRRR]

If possible I would keep the SWA continueous and do-away with adding a joint box, nowt wrong with drill a hole and running the cable inside to out , just gun a wee bit of silicone gel to seal the hole up nicely

Awesome that was what i was thinking, just couldn't get away from feeling like a JB would look better but imo completely unnecessary

 

[littlespark]

There are ways of shaping the drill hole so the swa curves into the hole smoothly… then fill it afterwards.

 

[pc1966]

As above, avoid junctions unless there is no reasonable alternative.

Drilling the hole to slope slightly downwards towards the outside is advisable so any water tends to run out, not in.

Be aware the minimum bend radius for SWA, and most cables, is around 8 times the diameter. With even a fairly thin 10mm cable that is quite a gentle bend, think big drain pipe sort of bend. If you can shape the inside/outside to avoid too tight a bend and fill after with silicone or mortar then it is quite practical just to run it in.

If you absolutely have to have a sharp bend then terminating in a box on the wall and taking just the cores inside via trunking, conduit, etc, through the wall is an option as individually the cores will be OK for a far smaller bend. Try and keep them in the rubber sheath thing the armour sits on as far as possible, unless big and cores too stiff to manipulate without separating them.

 

[Dustydazzler]

Awesome that was what i was thinking, just couldn't get away from feeling like a JB would look better but imo completely unnecessary

Never joint a cable unless A its too short or B it is damaged

Okay yes there are occasions where the sparks might need to go from SWA to T&E due to access issues but if you can keep the SWA as one length from start to finish then 100% this is the best install method

Why waste money and time fitting an unnecessary JB