Weird looking wiring, two gang lighting switch

[Tenchijin]

Hi all,
I've just popped off a two gang switch we have on our landing upstairs. It controls the main landing light one side, which is a two way switch with another single switch at the bottom of the stairs , and the family bathroom light on the other side that is a one way.
I was planning to replace it with a two gang dimmer switch.

When I popped it open I was met with the below. Firstly, is this normal? It seems like an excessive amount of wiring to other switches I've looked at / changed in the past. The only explanation I can think of it that we have an extractor in the ceiling of the family bathroom. I guess that could be why its been bridged between the two switches?
This is a new build so nothing would surprise me.

Secondly, is it going to be possible to replace this with a two way dimmer switch? The one I have purchased has L1, L2 and a C.

I suspect this will be a job for a professional sparky, but wanted to see what I could figure out with some help first

All input welcomed

P.S novice DIY'er here so go easy on me

 

[westward10]

All those blues are neutrals. There are several methods for lighting circuits and a common practice now is to loop the neutrals at the switches, this can aid the use of "smart" accessories in the future. The blues at the switch terminals are nothing to do with the switching they are just "parked" there to terminate them, looks like one has come out. If you replace the switch you need something like this to connect the neutrals Compact Push Wire Connector 2.5mm 5 Way - https://www.tlc-direct.co.uk/Products/WA205.html?source=adwords&ad_position=&ad_id=415703895078&placement=&kw=&network=u&matchtype=&ad_type=&product_id=WA205&product_partition_id=934892185560&campaign=shopping_cable_accessories&version=finalurl_v3&gclid=CjwKCAjwhYOFBhBkEiwASF3KGYCi1RdwhmDkguRRKcJUp6Lty32xV7Y26p8W0-vCIhn6lI3g1FuFdhoCbpIQAvD_BwE
It can be replaced but if you decide to do it ensure you mark where each conductor came from or take pics but with them all being brown it will be easy to mix them up. May be an easy job for an electrician

 

[Dartlec]

That's an unusual switch to be honest, though it does also appear to have been messily installed...

The additional (blue) wires you have there are neutrals, hopefully all from one circuit (upstairs lighting I'd guess).

Normally they do not connect to the switch because they must never be switched - the switch only ever going in the live(line - brown conductor), but they are commonly terminated separately in the back box. The switch you have there appears to have a termination for them, but it is not connected electrically to anything else...

There do seem to be a lot of neutrals for the setup you describe, so it may be worth having an electrician check it over.

One of the cables (grey with blue oversleeving) is likely on a 3 core & Earth cable that runs to an isolator switch for the fan...

The blue wire that has popped out should be carefully reterminated (with the power to that circuit off).

To replace with a 2 gang dimmer switch the neutrals will need to be terminated separately as Westward10 has mentioned - though with 2 dimmers the cables will have to be trimmed back quite a bit to fit everything in I suspect.

 

[Tenchijin]

Thank you both, all makes sense and I've learned a bit too, which is good!

As I suspected, I'll need an expert to take a look for me. I've already dropped my local electrician a message

Thanks for the input

 

[Flanders]

As above but just to add it may be difficult to fit a dimmer switch . As a dimmer takes up a lot of space and the terminals tend to be small . I personally would not be wanting to swap that switch force dimmer

 

[Dartlec]

Thank you both, all makes sense and I've learned a bit too, which is good!

As I suspected, I'll need an expert to take a look for me. I've already dropped my local electrician a message

Thanks for the input

Hager generally make good accessories, so if that's what is installed throughout it's hopefully a good sign of the overall quality of the installation...

 

[Tenchijin]

Hager generally make good accessories, so if that's what is installed throughout it's hopefully a good sign of the overall quality of the installation...

Well that's good to hear, hopefully it'll be possible for the professional to sort out for me