Running extra wire for lights

[DogsBody]

I want to put in some extra lights in my new house in the kitchen.
I don't have access from the floor above and I want to make as little mess as possible.

I have spot lights on a dimmer switch that is located at one end of the room, then I have a light fitting with a diummer switch at one end and a normal switch by the back door.

I want to install 2 extra spot lights on the first circuit and an extra light fitting on the 2nd circuit.
I think I know the answer to this but wanted to hear other peoples thoughts first.

Ideally this would be done with minimal mess in order to minimise redocrating.

Both lights wiring would have to be run through the joists as the run accross the room and I want to put the lights in further down the room, how many joists however I do not know as the ceiling currently has not been touched by me.
Switches are not inline with where I want to put the ligthts either.
What options do I have ?

I imagine my only option is to start making big hole sin the ceiling, which I am hoping I can avoid

 

[DogsBody]

I thought that would be the answer.
Just cut it with an angle grinder ?

How do you make sure you dont hit any existing wires with the angle grinder/cutting tool when cutting a strip out of the ceiling ?

 

[DogsBody]

No

Just use a straight edge & stanley knife & score it a few times, or use a Oscillating Multi-Tool, plasterboard is only 9.5mm or 12.7mm thick.

Unlikely you will hit any wires, as they are usually placed 50mm down from top of a joist.

But but but, angle grinder would be soooo much faster
In all seriousness, your help is much appreciated.

Next question.
light at bottom of stairs only has switch at bottomof stairs, what would be teh correct route to run a wire to top of stairs,
I assume straight up to attic then back down again to the switch location?

This will not be possible in my house however so I would have to try and run one up thesloping ceiling above the stairs, unless this breaks some sort of code ??