Would you recommend installing a 4 gang or 2x 2 gang light switch next to each other?

[j0hnnn]

I'm considering light switch options for two outdoor lights (soffit + wall light) and indoor lights (porch + hallway). The switches are going to be located inside the house (hallway as you enter) next to the door. The outdoor and indoor lights will be on a separate circuit and I'm trying to figure out if it's best to separate these out into two different fittings or a single 4 gang back box.

Something to consider is that I may in the future add smart relays to the switches and the back boxes will be 35mm, I just don't know if a single 4 gang would make sense given the space required for the 2.5mm T&E cables and relays. Although, it does seem to offer the "cleaner" look. Thoughts?

 

[littlespark]

It doesn’t matter if the switches are on different circuits… so you can have a 4 gang if you wanted to.

On the other hand, it could be quite cluttered with wires behind the switch, and confusing if complex wiring.

If you’re able to, put in boxes deeper than 35mm…. Just for the future planning of smart switches.

 

[j0hnnn]

It doesn’t matter if the switches are on different circuits… so you can have a 4 gang if you wanted to.

On the other hand, it could be quite cluttered with wires behind the switch, and confusing if complex wiring.

If you’re able to, put in boxes deeper than 35mm…. Just for the future planning of smart switches.

Yea, gotcha, I just figured I'd mentioned they are different just so there is a clear separation in the actual switches. I'm just debating if I should go 4 gang for a nicer look or 2x 2 gang for more space.

I thought going 35mm would already be enough for smart switches since 25mm (or even 16mm) is what causes issues. I don't know if 47mm is actually normal for lighting switches. Do you really think I should go deeper?

 

[littlespark]

It’s easier to go deeper now in the roughing stage.

Many smart switches ask for 35mm, but it can still be a squeeze.

Did you mean 1.5mm cable in the OP? 2.5 is a bit big for lighting.

 

[j0hnnn]

I'll have a think about going deeper, thanks. Oh yea, typo, I did mean 1.5mm. I think I'll just do 2x 2gang since it might be less of a squeeze down the line if I do have to put a few relays in there. Seems minor but a fundamental decision whether to cut for one box or two .

 

[GroovyG]

Just a thought - it could be more user-practical to have two separate plates, especially if fumbling around for them in the dark.
G.

 

[mark H]

I'll have a think about going deeper, thanks. Oh yea, typo, I did mean 1.5mm. I think I'll just do 2x 2gang since it might be less of a squeeze down the line if I do have to put a few relays in there. Seems minor but a fundamental decision whether to cut for one box or two .

I’ve just done EXACTLY the same but used a 4gang BGNexus that separates the four rockers into two groups of two

 

[SparkySy]

I did a conversion from a standard 3 gang switch to a lightwave smart 3 gang switch the other day, they recommend a 35mm box but it was very tight and a 47mm would have left more room for the cables, I ended up using the spacing adapter that comes with the switch to get the extra depth.
If you're planning on upgrading to smart switches I would put a 47mm box in and make sure the cable entry is as far back as possible.
Oh and definitely have a neutral at the switch as well!
Sy

 

[brianmoooore]

Get a 47mm in while you can. I haven't fitted a 16mm box since not long after I started, fitted 25mm for light switches for many years, but for the last several years, I've fitted a minimum of 35mm for everything except cooker and shower switches.
You can't have too much room in a metal box.

 

[littlespark]

Another tip for metal boxes, the single box version…. Is to fold flat the fixing lugs that you won’t be using… the top and bottom ones